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TP53 gene mutations are common in myelodysplastic syndromes (MDS). Previous studies have reported their detrimental effects on patient survival. However, current treatment strategies mainly based on hypomethylating agent therapy (HMA) and hematopoietic stem cell transplantation (HSCT) still leave a lot to be desired. And there is also a lack of studies on large sample with a view to the refinement of specific characteristics and disease progression. So we performed a meta-analysis including 20 studies compromising 5067 patients to assess the prognostic impact and clinical characteristics of TP53 mutations in MDS patients. The overall hazard ratio for overall survival (OS) was 2.14 (95% confidence interval 1.94-2.37, P.00001) compared with patients with MDS without TP53 mutations. Lower progression-free survival and leukemia-free survival were associated with TP53 mutations. Subgroup analysis revealed that TP53 mutations were significantly associated with high levels of blast cells and karyotypic aberrations. And among Asian population, the adverse impact on OS of TP53 mutations seemed worse than those in Western countries. (HR 2.87 vs. 2.02, P = .01). In addition, TP53 mutations had no effect on response to HMA therapy, and HSCT improved OS in patients carrying TP53 mutations.

Resume Le traitement des carcinomes endometriaux repose essentiellement sur les donnees histopathologiques de type histologique, de grade, de stade et d’emboles vasculaires. Nous revenons sur les modifications recentes de l’appreciation de ces parametres, en lien avec la derniere classification OMS 2020. Par ailleurs, le typage moleculaire des carcinomes endometriaux est devenu la regle car il est associe a des implications pronostiques et therapeutiques fortes. Les categories TP53-mutee/serous like et hypermute/dMMR sont facilement identifiables par le pathologiste a l’aide d’outils immunohistochimiques. La categorie ultramutee/POLE-mutee requiert quant a elle des techniques de sequencage. Nous detaillons ici comment apprehender de facon simple cette nouvelle classification histo-moleculaire, maintenant partie integrante des recommandations des societes savantes.

Background Mutations in TP53 in myeloid neoplasms patients have been associated with poor prognosis. Effective treatments to these patients remain unclear. Patients and Methods In this study, we retrospectively analyzed diagnostic and outcomes of 31 Acute Myeloid leukemia (AML) and 9 Myelodysplastic syndromes (MDS) patients with TP53 mutation at our hospital from September 2015 to October 2020. Results A total of 42 variants (28 unique variants) in the coding region of TP53 gene were identified, and most were missense mutation (34 of 42, 81%). The median overall survival (OS) was 8 months for the AML patients (1-32 months) and 7 months for the MDS patients (3-27 months). There were 35 and 13 patients underwent frontline chemical therapy and Allo-HSCT, respectively. The overall response rate was 45.3% (16/35) for the frontline treatment. There was no significant difference between intensive and low-intensity regimens on either response to the frontline treatment (P = .255) or overall survival (P = .078). Patients, who achieved complete or partial remission at the frontline treatment, presented a higher survival than patients in non–remission, no matter transplant or not. Conclusion This study corroborates that improving the response to the first-line treatment could prolong the survival of myeloid neoplasms patients with TP53 mutation. Allo-HSCT could be a curative option for patients with TP53 mutation, when in complete remission during the first-line treatment.

Despite recent success in regard to targeted therapies in chronic lymphocytic leukemia (CLL), patients with TP53 disruption (including deletion and/or mutation) continue to have poor outcomes compared with other patients with CLL. In this article, a review of common TP53 mutations in CLL, and recent trials using novel targeted agents in CLL patients with TP53 disruption, is provided with the goal of emphasizing the need to continuously focus on this area of research. In addition, limited but available data on double refractory CLL to BTK inhibitor and BCL-2 inhibitor, and on Richter syndrome, are reviewed.

By implementing dynamic circulating tumor DNA (ctDNA) analysis, we explored the impact of TP53 mutations on tumor evolution and resistance mechanisms to ensartinib in patients with ALK-positive NSCLC.In a multicenter phase 2 trial, patients with ALK-positive NSCLC who progressed on crizotinib were treated with ensartinib. Blood samples for ctDNA analysis were collected at baseline, cycle 3 day 1, and progression disease (PD) and analyzed with a 212-gene panel.A total of 440 samples were collected from 168 patients. Baseline TP53 mutations (20.2%) significantly correlated with inferior progression-free survival (4.2 mo versus 11.7 mo, p0.0001). Patients with TP53 mutations had higher mutation load than those without TP53 mutations at baseline (13.79 ± 3.72 versus 4.67 ± 0.39, p0.001). Although there was no significant difference in mutation load between these groups at cycle 3 day 1 (5.89 ± 2.25 versus 3.72 ± 0.62, p = 0.425), patients with mutated TP53 developed more mutations at PD (7.07 ± 1.25 versus 3.20 ± 0.33, p = 0.003). Frequency and abundance of secondary ALK mutations G1269A, G1202R, and E1210K increased markedly at PD than baseline. In patients without secondary ALK mutations, we identified ALK-independent resistance mechanisms including bypass signaling activation, downstream effector protein reactivation, epithelial-mesenchymal transformation, and epigenetic dysregulation.Our study highlighted the advantage of ctDNA analysis for monitoring tumor evolution. TP53 mutations promoted genetic evolution and accelerated occurrence of resistance. We also unveiled ALK-dependent resistance mechanisms, mainly by G1269A, G1202R, and E1210K mutations, and ALK-independent resistance mechanisms to ensartinib.

OBJECTIVES: Mutations in the TP53 tumor suppressor gene are common in ovarian carcinoma (OC) but their impact on outcomes is controversial. We sought to define the relationship of TP53 mutations to cancer outcomes and their interactions with co-occurrent BRCA1 or BRCA2 (BRCA) mutations, comparing three different TP53 mutation classification schemes. METHODS: We performed next generation sequencing on 393 cases of OC prospectively followed for survival. TP53 mutations were classified according to three schemes termed Structural, Functional, and Hotspot. Mutation distribution was compared between cases with and without BRCA mutations. In a subset of 281 cases of high grade serous carcinoma (HGSC), overall survival was compared using Kaplan-Meier curves, logrank testing, and multivariate Cox regression analysis, both stratified and adjusted for BRCA mutation status. Multivariate logistic regression was used to analyze the effects of TP53 mutation type on platinum resistance. RESULTS: TP53 mutations were identified in 76.8% of the total cohort (n=302/393) and 87.9% of HGSC (n=247/281). Cases with BRCA mutations demonstrated significantly higher TP53 mutation frequency overall (n=84/91, 92.3% vs. n=218/302, 72.2%, p

Objectives Epidermal growth factor receptor (EGFR) exon 20 insertion (ex20 ins) mutations are generally associated with de novo resistance to first- or second-generation EGFR tyrosine kinase inhibitors in non-small cell lung cancer (NSCLC). However, the real efficacy of osimertinib for this subset remains elusive. We performed this study to investigate the real efficacy of osimertinib for Chinese advanced NSCLC patients harboring EGFR ex20 ins mutations. Materials and methods We retrospectively collected data of metastatic NSCLC patients with EGFR ex20 ins mutations who were treated with osimertinib 80 mg or 160 mg once daily in our center from June 2017 to May 2020. Progression-free survival (PFS), objective response rate (ORR) and disease control rate (DCR) were assessed. Results A total of 62 cases with EGFR ex20 ins mutations were included, and the major insertion variant was D770_N771insSVD and V769_D770insASV (45.1 %). Concurrent TP53 mutation was most commonly observed (59.7 %). Four patients showed partial response, 29 cases with stable disease and 29 showed progressive disease as best response to osimertinib (ORR: 6.5 %, DCR: 53.2 %). The median PFS (mPFS) in total patients was 2.3 (95 %CI, 1.5–3.1) months. Patients harboring A763_Y764insFQEA/D770delinsGY variants showed numerically longer mPFS than those with other variants (4.2 vs. 2.2 months, P = 0.164). Patients who failed to osimertinib and occurred extracranial progression showed similar mPFS to those with intracranial progression (2.3 vs. 1.9 months, P = 0.142). Median PFS was not significantly different between patients who received osimertinib 80mg or 160mg once daily (2.5 vs. 1.3 months, P = 0.161), either with no significance when it used in fist-line setteing or bove (3.0 vs. 2.2 months, P = 0.639). Conclusion The unique insertion variant A763_Y764insFQEA and D770delinsGY might better respond to osimertinib than other ex20 ins subtypes. Osimertinib either 80 mg or 160 mg once daily showed less activity in Chinese NSCLC patients harboring diverse EGFR ex20 ins mutations.

TP53 mutations are implicated in the progression of mucinous borderline tumors (MBOT) to mucinous ovarian carcinomas (MOC). Optimized immunohistochemistry (IHC) for TP53 has been established as a proxy for the TP53 mutation status in other ovarian tumor types. We aimed to confirm the ability of TP53 IHC to predict TP53 mutation status in ovarian mucinous tumors and to evaluate the association of TP53 mutation status with survival among patients with MBOT and MOC. Tumor tissue from an initial cohort of 113 women with MBOT/MOC was stained with optimized IHC for TP53 using tissue microarrays (75.2%) or full sections (24.8%) and interpreted using established criteria as normal or abnormal (overexpression, complete absence, or cytoplasmic). Cases were considered concordant if abnormal IHC staining predicted deleterious TP53 mutations. Discordant tissue microarray cases were re-evaluated on full sections and interpretational criteria were refined. The initial cohort was expanded to a total of 165 MBOT and 424 MOC for the examination of the association of survival with TP53 mutation status, assessed either by TP53 IHC and/or sequencing. Initially, 82/113 (72.6%) cases were concordant using the established criteria. Refined criteria for overexpression to account for intratumoral heterogeneity and terminal differentiation improved concordance to 93.8% (106/113). In the expanded cohort, 19.4% (32/165) of MBOT showed evidence for TP53 mutation and this was associated with a higher risk of recurrence, disease-specific death, and all-cause mortality (overall survival: HR = 4.6, 95% CI 1.5-14.3, p = 0.0087). Within MOC, 61.1% (259/424) harbored a TP53 mutation, but this was not associated with survival (overall survival, p = 0.77). TP53 IHC is an accurate proxy for TP53 mutation status with refined interpretation criteria accounting for intratumoral heterogeneity and terminal differentiation in ovarian mucinous tumors. TP53 mutation status is an important biomarker to identify MBOT with a higher risk of mortality.

Rationale and Objectives In hepatocellular carcinoma (HCC), the tumor protein 53 (TP53) gene is frequently mutated and the mutations have been associated with poor prognosis. We aim to retrospectively identify the relationship between TP53 mutation status, tumor size (long-axis diameter, short-axis diameter, and long-to-short-axis ratio [L/S ratio]), margin and multifocality in surgically resected HCC. Materials and Methods The image features and TP53 mutation data from 78 patients generated with National Cancer Institute's multi-institutional The Cancer Genome Atlas (TCGA)/The Cancer Imaging Archive databases were assessed. Binary logistic regression analyses were performed to identify independent factors of harboring TP53 mutation status. The final model was selected by using the backward elimination method. Results TP53 mutations were found in 19 (31.5%) of 78 patients. TP53 mutation rates were significantly higher (a) in L/S ratio ≤ 1.2 14 of 41 [34.1%]) lesions than in L/S ratio >1.2 lesions (five of 37 [13.5%]) (p = 0.034) and (b) in nonmultifocality (17 of 54[31.5%]) than in multifocality lesions (two of 24 [8.3%]) (p = 0.028). On univariate logistic regression analysis, L/S ratio (≤1.20 vs >1.20. odds ratio [OR]: 3.319; p = 0.040; 95% confidence interval [CI]: 1.059–10.401 Area Under Curve (AUC) = 0.634) and multifocality (no vs yes OR: 5.054; p = 0.041; 95% CI: 1.065–23.986 AUC = 0.640) were associated with TP53 mutations. On multivariate logistic regression analysis, L/S ratio (≤1.20 vs >1.20 OR: 3.430; p = 0.040; 95% CI: 1.058–11.118) and multifocality (no vs yes OR: 5.232; p = 0.041; 95% CI: 1.072–25.526) were associated with TP53 mutations. The area under the receiver operating characteristic curve for predicting TP53 mutation status was 0.714 (95% CI: 0.590–0.837). Conclusion Our study focusing on identifying imaging aspects related to TP53 positive HCC. L/S ratio of HCC in combination with multifocality might be used to prognosticate TP53 mutation status. And the discriminatory power for this prediction model was good.

Recent advances in chronic lymphocytic leukemia (CLL) includes description of disease genomic landscape, inclusion of prognostic relevant genetic tests in CLL workflow and evaluation of minimal residual disease (MRD)1 in parallel with the increase availability of novel therapy agents.In this review, the theoretical and practical aspects of response assessment have been discussed. These are based on updated recommendations of the European Research Initiative on Chronic Lymphocytic Leukemia (ERIC) for genetic tests (TP53 mutation and IGHV status) and flow cytometry analysis for CLL. Methodological approaches and interpretation of results were also discussed.2,3

High-grade neuroendocrine carcinomas (HGNEC) of the cervix are rare and carry an extremely poor prognosis. Fortunately, there have been recent advances in our molecular understanding of these carcinomas and some advances offer novel therapeutic options. The vast majority of HGNEC of the cervix are associated with human papillomavirus (HPV) and would be prevented by currently available vaccines. TP53 mutations are variably identified and likely drive a second pathway, one unrelated to high-risk HPV. Most carcinomas express VEGF and some patients have seen durable response to therapy with the addition of a VEGF inhibitor. PIK3CA mutations are among the most common mutations identified and mTOR inhibitors may be considered in these cases. KRAS mutations can be identified; an impressive response to MEK inhibitors has been seen in one case. PD-L1 positivity is frequently seen and complete responses to PD-1/PD-L1 inhibitors have been reported. These molecular advances offer numerous approaches to targeted personalized therapy.

KRAS mutations are one of the most prevalent alterations in non-small cell lung cancer. However, patients with this driver alteration present heterogeneous clinical outcomes. In this study, we have explored the potential clinical impact of coexisting alterations in this subset of patients.Samples from a cohort of 69 lung adenocarcinoma patients homogenously treated with platinum doublet as first-line therapy were evaluated using targeted next generation sequencing (NGS). Mutations and copy number alterations were assessed in 37 advanced KRAS-mutant (KRASm) and in 32 KRAS wild-type (KRASwt).TP53 was the most frequent additional alteration found in both cohorts. Interestingly, TP53 mutations were more frequent in KRASwt than in KRASm patients (80 % vs. 34 %; p 0.05) as well as STK11 mutations (17 % vs 8 %, p=NS). FGFR3 mutations were only found concomitantly with KRASm (11 %). No genomic co-alteration had an impact on overall survival within the KRASm patients treated with chemotherapy.KRAS mutated lung adenocarcinoma is a heterogeneous entity and comprehensive characterization of co-alterations using NGS may lead to more accurate patient stratification.

Objective Invasive mucinous adenocarcinoma (IMA) is a variant of lung adenocarcinoma. We present one case of IMA with mixed mucinous and non-mucinous components, suggesting stepwise progression within the tumor. Material and method The two different components of IMA were separately examined by immunohistochemistry and performed amplicon sequencing (Ion Ampliseq Cancer Hotspot Panel v2, ilumina, San Diego, CA). Result Macroscopically, the IMA contained a small and well demarcated solid part. Tumor cells in the main part showed abundant intracytoplasmic mucin, whereas those in the solid part showed scant intracytoplasmic mucin and high-grade nuclear atypia. Both parts harbored the same KRAS p.G12 V mutation. The amplicon sequencing of the IMA showed oncogenic TP53 p.P278 L mutation was detected only in the solid part. Conclusion Oncogenetic TP53 mutation might promote stepwise progression of this case of IMA.

Patients with AML that develops after cytotoxic therapy (tAML) have overall inferior outcomes relative to de novo AML due to both patient-related factors and the intrinsic biology of the disease. Treatment of patients with tAML is challenging. The key initial clinical decision is whether a patient is a candidate for or likely to benefit from intensive induction chemotherapy, a determination which we argue should not be predicated on chronologic age alone. For those determined likely to tolerate intensive induction chemotherapy, CPX-351 is likely superior to conventional induction with cytarabine and daunorubicin. For those deemed inappropriate for intensive induction, hypomethylating agents have the strongest evidence base in elderly adults with AML, and are an attractive option in tAML. This is particularly true in patients with TP53 mutations who are less likely to respond to conventional induction chemotherapy. Exciting options on the therapeutic horizon for tAML include combination therapies incorporating BCL2 inhibitors, Hedgehog pathway inhibitors, and isocitrate dehydrogenase inhibitors.

Therapy-related myeloid neoplasms (t-MNs) are the most serious late complications in patients treated with traditional cytotoxic chemotherapy and/or radiation. T-MNs are aggressive and chemorefractory hematologic malignancies, with a median survival of less than 6 months. TP53 mutations are highly enriched in t-MN patients, though the mechanism for this selective enrichment has only come to light over the past several years. In this review, we discuss the history and function of p53, and the role of TP53 mutations in the origin and progression of t-MNs. Emerging data has begun to elucidate who may be at highest risk of developing t-MNs, which ideally will enable us to develop preventative strategies for this devastating disease. As t-MNs may not be avoidable, novel therapies are urgently needed for this patient group and are underway as exemplified by recent investigation in restoring wild-type p53 function as well as directly targeting TP53 mutant variants. With better prevention and treatment, outcomes will hopefully begin to improve in the near future.

We retrospectively analyzed 101 primary MDS patients with complex karyotype during January 2010 and April 2017.The median overall survival (OS) time was 13 (95% CI 9.98-16.02) months, and there was no significant difference in OS for different treatment. Chromosome 5/7 involvement was common (78.22%, 79/101) and associated with shorter OS (12 months vs. 28 months, P 0.01) Monosomal karyotype (MK) is overlapped with CK in 79 patients, but was not statistically associated with shorter OS. While in 59 cases with genes sequenced, 57 (96.61%) patients were found to have at least one mutation of known significance, and TP53 was the most frequent (74.58%, 44/59), the median OS of patients with TP53 mutation was shorter than those without (10 vs. 27 months, P 0.01). Multivariate analysis demonstrated that only TP53 mutation was the strongest independent prognostic factor for OS. Moreover, high variant allele frequency (VAF) of TP53 mutation (median VAF was 70.00%) was seen and associated with adverse survival (9 months vs. 13 months, p = 0.04). In conclusion, MDS patients with CK implied an unfavorable outcome regardless of any treatment, TP53 mutation occurs at a high frequency and has a higher VAF, both were associated with worse survival.

Background: Functional heterogeneity among TP53 mutations necessitates a need to dissect the prognostic potential of TP53 mutations at different sites or against different molecular background. Methods: The information of TP53 mutations and overall survival time among 7572 patients with metastatic cancers in the MSK-IMPACT clinical sequencing cohort were collected. The effects of TP53 mutations on survival were conducted using the Kaplan-Meier approach, log-rank test and Cox regression model in pan-cancer, and in major subtypes of lung, breast, and colon cancers. Findings: Mutations in exons 4, 5, 6, 7, 8, and 10, p.R342*, p.Y220C, and p.G245S were identified as potential pan-cancer poor prognosticators (p < 0.05 for all). R213* was identified as a significant poor prognosticator only in metastatic lung adenocarcinoma (p = 0.01). The negative prognostic effect of mutated TP53 was statistically significant in lung adenocarcinoma patients harboring EGFR p.L858R (p = 0.002), but not in those with exon 19 deletion (p = 0.173). Compared with wild-type TP53, higher risk of death correlated with TP53 mutational status located in exon 4, 5, 6, 7, or 8 among patients with metastatic breast invasive ductal carcinoma. In addition, p.R282W substitution was significantly associated with poor prognosis in metastatic colon adenocarcinoma (mCOAD), while TP53 mutation was also significantly negative associated with poor survival in COAD patients carrying driving mutations (KRAS or RAS/RAF). Interpretation: The prognostic values of TP53 mutation depended on cancer type and concurrent genomic abnormality. Our results may facilitate prognosis, patient identification for further investigation, and development of TP53 -targeted anti-cancer therapy. Funding: This work was supported by the Logistics Support Department of PLA [grant number 19BJZ03, 2019], Military Medicine Fund of Changzheng Hospital [grant number 2019CZJS208-1, 2019], Science and Technology Commission of Shanghai Municipality [grant number17511103403, 2017], Medical Innovation Research Project of Shanghai Science and Technology Commission (grant number 20Y11914400, 2020), Chinese National Natural Science Funding [grant number 82002522, 2020]and State Key Program for Chronic non- communicable Disease Prevention and Control of the Ministry of Science and Technology, China (grant number 2017YFC1309202, 2017). Declaration of Interest: All authors declare no conflicts of interest.

TP53 mutated acute myeloid leukemia (AML) responds poorly to chemotherapy and has a short overall survival rate with a median of 5–9 months. Poor outcomes in TP53 mutated AML following chemotherapy have been observed and treatment options remain limited, although the presence of TP53 mutations alone should not be a barrier to therapy. Decitabine is emerging as an alternative treatment option for patients with TP53 mutated AML, although the agent has not been associated with deep molecular remissions and requires additional consolidation. The clinical and genomic characteristics of TP53 mutated AML are reviewed in this paper.

TP53 mutation (TP53mut) and a complex karyotype (CK) were shown to be predictors of poor outcome in mantle-cell lymphoma (MCL). In this study we examined the combined effect of both of these risk factors.Patients diagnosed with MCL between January 2000 and December 2014 (n = 74) were evaluated. Forty-eight of them had available material for TP53 and cytogenetic examination. We analyzed the prognostic effect of combined TP53mut and CK in the cohort of patients treated with rituximab-containing therapy.Three-year (3-y) overall survival (OS) and 3-y progression-free survival (PFS) in CK patients were shorter compared with non-CK (P = .001 for OS; P = .02 for PFS). TP53mut was a predictor of shorter survival compared with TP53 wild type (OS and PFS; P .001). The incidence of TP53mut was not significantly associated with CK (P = .240). CK and TP53mut were predictors of inferior PFS and OS independent of age and Mantle-Cell Lymphoma International Prognostic Index, with hazard ratios of 2.35 (P = .024), 4.50 (P .001) for PFS and 4.31 (P .001), 5.46 (P .001) for OS analysis in the CK and TP53mut groups, respectively. The combination of TP53mut and CK status stratified the patients into 3 prognostic groups (P .001) with the worst outcome in patients with CK and TP53mut.TP53 mutation and CK occurred independently and patients harboring both had a dismal prognosis. The study suggests the importance of molecular cytogenetics and examination of the TP53mut status to be performed simultaneously before treatment.

The prognostic value of TP53 in advanced non-small-cell lung cancer (NSCLC) is unclear. Whether different mutated exon has different prognostic value is unknown. We sought to reveal the prognostic value of TP53 in advanced NSCLC, as well as the correlation with EGFR mutation.Information regarding TP53 and EGFR alterations and patients' survival time in advanced NSCLC was downloaded from the Cancer Genome Atlas Database. We further subdivided TP53 and EGFR mutation into subgroups based on different mutation exon, and then evaluated the distribution of different mutation exon as well as the prognostic value.Overall, 1441 pieces of data from 1441 metastatic NSCLC patient were collected. Mutation rate of TP53 was 56.1% (809/1441). TP53 mutation was a negative prognostic factor for OS. The estimated survival time for wild type TP53 and mutated TP53 was 27.0 months (95% CI, not reached) and 19 months (95% CI, 16.62 to 21.38), respectively, (p 0.001). We divided TP53 mutations into 4 groups, OS in these 4 groups was 27 months (95% CI, not reached), not reached, 21 months (95% CI, 17.16 to 24.84) and 13 months (95% CI, 10.39 to 15.61). The difference was statistically significant (p 0.001). Patients with EGFR exon 19/21 or non-exon 19/21 mutation demonstrated a higher rate of mutated type TP53 than EGFR wild type patients. Survival curve in EGFR wild type patients indicated that TP53 wild type patients had the best prognosis. In patients with exon 19/21 mutated EGFR, the trend was the same (P 0.001).TP53 mutation is a negative prognostic factor in advanced NSCLC, different mutated exon has different prognostic value. When coupled with EGFR mutation, we can predict the prognosis of advanced NSCLC patients more accurately.

Differentiation between multiple primary lung cancers and pulmonary metastases (PM) has important implications in staging, prognosis, and treatment strategies. Clinical and immunohistopathologic criteria have been standardized; however, a substantial number of cases remain difficult to classify. Using next-generation sequencing, it is now possible to improve the classification of multiple lung cancer lesions. This study systematically investigated the value of routine morphologic and IHC characteristics, p53 protein expression, TP53 mutation analysis, and 50-gene panel sequencing (GPS) in 111 lesions from 50 patients with multiple lung lesions. Based on immunohistopathologic criteria, 32 paired lesions were classified as multiple primary lung cancer (MPLC) and 21 as PM. TP53 mutation analysis indicated MPLC in 23 and PM in 6 pairs, but in the majority of cases (n = 28, 49%) no mutation was observed and no conclusion could be drawn. In contrast, only 2 pairs were not conclusive using GPS. In a significant number of matching tumor samples (n = 19, 39%), sequencing results were contradictory to the initial immunohistopathology diagnosis. No separation in overall survival for classifications based on immunohistopathology was observed, while a clear but nonsignificant trend was observed concerning survival in MPLC patients (hazard ratio=3.98) using 50-gene GPS. In about one-third of the patients, GPS provided additional information to improve the differentiation between MPLC and PM.

Undifferentiated endometrial carcinoma is an aggressive type of uterine cancer, which is occasionally associated with a low-grade endometrioid carcinoma component. This combination is referred to as "dedifferentiated endometrioid endometrial carcinoma." Neuroendocrine expression may occur in undifferentiated endometrial carcinoma, but its significance in dedifferentiated endometrial carcinomas is unknown. To gain insight into the pathogenesis of these tumors we have analyzed the immunophenotype (ARID1A, MLH1, PMS2, MSH2, MSH6, p53, (beta-catenin, SMARCB1, synaptophysin, chromogranin A, and CD56) and mutational status (PTEN, KRAS, PIK3CA, TP53 and POLE) of 4 dedifferentiated endometrial carcinomas with strong and diffuse neuroendocrine expression. All tumors demonstrated neuroendocrine expression in >= 70% of the cells in the undifferentiated carcinoma areas. Loss of expression of at least 1 DNA mismatch repair protein was observed in 2 cases, and p53 immunoreaction was aberrant (mutated/inactivated) in one case. All carcinomas were negative for beta-catenin and maintained nuclear SMARCB1 (INI1) and ARID expression. Three tumors shared identical endometrioid molecular profile (PTENand/orP/K3CA mutations) in both components. One tumor had POLE exonuclease domain mutation in the undifferentiated component. In one case, TP53 mutation was found exclusively in the undifferentiated component. Two patients died with peritoneal carcinomatosis and abdominal metastases, respectively; one patient died of a renal failure without evidence of disease, and the last patient is alive and free of disease at 3.3 years. Dedifferentiated endometrial carcinomas with neuroendocrine features are clinically and molecularly heterogeneous tumors. Probably, these carcinomas might acquire undifferentiated phenotype through mutations in TP53 and POLE. (C) 2017 Elsevier Inc. All rights reserved.

Endometrial carcinoma, which is associated with a mortality rate of approximately 20%, is the most common gynecological malignancy in the Western world. It is a heterogeneous disease, with multiple histotypes, each constituting a different disease entity. However, interobserver diagnostic agreement is suboptimal, particularly among the most lethal histotypes. Most recent data also indicate that histotype assignment is not independently associated with survival, while in contrast, clinicopathological risk stratification and genomic classification are significantly prognostic. Recent work has shown that there are four molecular subgroups of endometrioid carcinomas instead of the two types proposed by Bokhman in the 1970s. Carcinomas with polymerase E (POLE) exonuclease domain hotspot mutations are highly prognostically favourable; those with copy-number alterations and TP53 mutations are highly aggressive; and microsatellite unstable and 'copy-number low' endometrioid carcinomas are associated with intermediate prognoses. This review summarises the genetic foundations of the various histotypes of endometrial carcinoma and synthesises this information in the form of algorithms, or classifiers, that recapitulate genomic classification that is not only prognostic, but also potentially diagnostic and therapeutically predictive. A review of Lynch syndrome and Lynch-like syndrome is also provided.

Objectives The purpose of this study was to assess the prognostic significance of a simplified, clinically accessible classification system for endometrioid endometrial cancers combining Lynch syndrome screening and molecular risk stratification. Methods Tumors from NRG/GOG GOG210 were evaluated for mismatch repair defects (MSI, MMR IHC, and MLH1 methylation), POLE mutations , and loss of heterozygosity. TP53 was evaluated in a subset of cases. Tumors were assigned to four molecular classes. Relationships between molecular classes and clinicopathologic variables were assessed using contingency tests and Cox proportional methods. Results Molecular classification was successful for 982 tumors. Based on the NCI consensus MSI panel assessing MSI and loss of heterozygosity combined with POLE testing, 49% of tumors were classified copy number stable (CNS), 39% MMR deficient, 8% copy number altered (CNA) and 4% POLE mutant. Cancer-specific mortality occurred in 5% of patients with CNS tumors; 2.6% with POLE tumors; 7.6% with MMR deficient tumors and 19% with CNA tumors. The CNA group had worse progression-free (HR 2.31, 95%CI 1.53–3.49) and cancer-specific survival (HR 3.95; 95%CI 2.10–7.44). The POLE group had improved outcomes, but the differences were not statistically significant. CNA class remained significant for cancer-specific survival (HR 2.11; 95%CI 1.04–4.26) in multivariable analysis. The CNA molecular class was associated with TP53 mutation and expression status. Conclusions A simple molecular classification for endometrioid endometrial cancers that can be easily combined with Lynch syndrome screening provides important prognostic information. These findings support prospective clinical validation and further studies on the predictive value of a simplified molecular classification system.

Introduction TP53 mutations are common in non-small cell lung cancer (NSCLC) and have been reported as prognostic of poor outcome. The impact of TP53 co-mutations in epidermal growth factor receptor (EGFR)-mutated NSCLC is unclear. Materials and methods Tissue from 105 patients with EGFR-mutated NSCLC at Princess Margaret Cancer Centre was analyzed by next-generation or Sanger sequencing to determine TP53 mutational status. Associations between TP53 status and baseline patient and tumor characteristics, treatments and outcomes (relapse-free survival [RFS] after surgical resection, overall survival [OS], overall response rate [ORR] and progression-free survival [PFS] on EGFR tyrosine kinase inhibitors [TKIs]), were investigated. Results Dual TP53/EGFR mutations were found in 43/105 patients (41%). Among 76 patients who underwent surgical resection, neither RFS (HR 0.99, CI 0.56–1.75, p = 0.96) nor OS (HR 1.39, CI 0.70–2.77; p = 0.35) was associated with TP53 status. Sixty patients (24 TP53 MUT; 36 TP53 WT) received first-generation EGFR TKIs for advanced disease. ORR was not significantly different (TP53 MUT 54%, WT 66%, p = 0.42). There was a non-significant trend towards shorter PFS on EGFR TKIs with TP53 mutation (HR 1.74, CI 0.98–3.10, p = 0.06). When limited to TP53 missense mutations (n = 17), PFS was significantly shorter (HR 1.91, CI 1.01–3.60, p = 0.04). Among 11 evaluable patients treated with T790M inhibitors, ORR was not significantly different (TP53 MUT 3/3 [100%], WT 7/8 [88%]). Conclusions Patients with dual TP53/EGFR mutations, especially missense mutations, had marginally lower response rates and shorter PFS when treated with EGFR TKI therapy. Larger datasets are required to validate these observations.

TP53 is a tumour suppressor gene frequently mutated in human cancers; nevertheless, in EBV-associated malignancies mutations are uncommon despite frequent deregulation of the p53 pathway. In this study, we aimed to investigate p53 expression, TP53 mRNA levels and TP53 mutations in EBV-associated gastric carcinoma (EBVaGC). A case-control study was performed using 46 patients: 15 EBVaGC and 31 EBV-negative GC (EBVnGC) cases. p53 expression was detected by immunohistochemistry (IHC), the evaluation of p53 mRNA levels was performed by RT-qPCR and TP53 mutations were investigated only in EBVaGC cases using the DNA sanger sequencing method. p53 expression was found in 97.8% (45/46) of all gastric cancer cases (including EBVaGC and EBVnGC groups). Despite the high frequency of p53 expression in both groups, the percentages of cells are significantly higher among EBVaGC cases (p = 0.027). Regarding the mRNA levels, we found a significantly increased expression of p53 mRNA in EBVnGC (2−ΔΔCt = 13.4 ± 2.4; p = 0.0029) when compared with EBVaGC. Furthermore, the sequencing analysis of TP53 gene revealed that only one of the 15 EBVaGC cases presented a missense mutation. Our results demonstrated that EBV-associated gastric carcinomas are characterized by a significant decrease of TP53 mRNA levels with a strong p53 expression and rare TP53 mutations when compared with EBV-negative cancers. Considering these results, EBV seems to induce a stabilization of p53 in the EBVaGC independently of the presence of mutations, which remains to be explained.

Objective Smoking remains a primary etiological factor in head and neck squamous cell carcinoma (HNSCC). Given that non-coding RNAs (ncRNAs), including PIWI-interacting RNAs (piRNAs), have emerged as mediators of initiation and progression in head and neck malignancies, we undertook a global study of piRNA expression patterns in smoking-associated HNSCC. Materials and methods Using RNA-sequencing data from 256 current smoker and lifelong nonsmoker samples in The Cancer Genome Atlas (TCGA), we analyzed the differential expression patterns of 27,127 piRNAs across patient cohorts stratified by tobacco use, with HPV16 status and tumor status taken into account. We correlated their expression to clinical characteristics and to smoking-induced alterations of PIWI proteins, the functional counterparts of piRNAs. Finally, we correlated our identified piRNAs and PIWI proteins to known chromosomal aberrations in HNSCC to understand their wider-ranging genomic effects. Results and conclusion Our analyses implicated a 13-member piRNA panel in smoking-related HNSCC, among which NONHSAT123636 and NONHSAT113708 associated with tumor stage, NONHSAT067200 with patient survival, and NONHSAT081250 with smoking-altered PIWIL1 protein expression. 6 piRNAs as well as PIWIL1 correlated with genomic alterations common to HNSCC, including TP53 mutation, TP53-3p co-occurrence, and 3q26, 8q24, and 11q13 amplification. Collectively, our findings provide novel insights into the etiology-specific piRNA landscape of smoking-induced HNSCC.

Objective TP53 mutation is the most frequent molecular event in BRCA1 -associated ovarian carcinomas. TP53 status may be a confounding factor in the evaluation of clinical importance of other proteins. We aimed to evaluate the clinical significance of BRCA1 mutations with respect to the TP53 accumulation status in 159 high-grade ovarian carcinomas. Methods Statistical analyses were done with the Kaplan-Meier method, log-rank test, the Cox's and logistic regression models for all patients, and in subgroups with and without TP53 accumulation (TP53+ and TP53−, respectively). Results Forty of 159 ovarian carcinomas (25.2%) were diagnosed in patients with BRCA1 germline mutations; 102 tumors (64.2%) were TP53+ and 57 (37.8%) were TP53−. Among patients with TP53+ carcinomas, BRCA1 carriers had increased odds of recurrence compared with sporadic cases (HR 2.25, P =0.003; median disease-free survival time 7.7 vs. 18.4months, respectively). In the smaller TP53− subgroup, BRCA1 mutation reduced the risk of death by 46% (HR 0.54, P =0.099, median overall survival time 42.7 vs. 28.1months), but beyond the border of significance. When the TP53 status was not taken into account, BRCA1 mutations did not show any significance, however, there was a trend toward increased odds of complete remission for women with BRCA1 mutations compared to non-carriers (OR 2.47, P =0.064). Taxane-platinum therapy showed advantage over the platinum-cyclophosphamide one in the entire group of patients and in the TP53+ subgroup. Conclusions Our results suggest that the TP53 accumulation status determines the prognosis of BRCA1 mutation carriers with high-grade ovarian carcinomas.

Background We analyzed whether co-occurring mutations influence the outcome of systemic therapy in ALK-rearranged non-small-cell lung cancer (NSCLC). Patients and methods ALK-rearranged stage IIIB/IV NSCLC patients were analyzed with next-generation sequencing and fluorescence in situ hybridization analyses on a centralized diagnostic platform. Median progression-free survival (PFS) and overall survival (OS) were determined in the total cohort and in treatment-related sub-cohorts. Cox regression analyses were carried out to exclude confounders. Results Among 216 patients with ALK-rearranged NSCLC, the frequency of pathogenic TP53 mutations was 23.8%, while other co-occurring mutations were rare events. In ALK/TP53 co-mutated patients, median PFS and OS were significantly lower compared with TP53 wildtype patients [PFS 3.9 months (95% CI: 2.4–5.6) versus 10.3 months (95% CI: 8.6–12.0), P

Background: TP53 gene is one of the most frequent alterations, and heterogeneity in immune cell content is found in hepatocellular carcinoma (HCC). However, TP53 mutations associated immunotype of HCC has not been reported. This study aimed to identify the TP53 mutations associated immunotype. Methods: The mutation annotation format (MAF) document, mRNA expression data and clinical data of HCC patients were downloaded from the publicly available TCGA (The Cancer Genome Atlas) data portal. 332 HCC patients were finally incorporate into this study. Infiltrating immune cells were evaluated by well-known CIBERSORT method. Another mutation data of HCC patients was downloaded from the COSMIC (Catalogue of Somatic Mutations in Cancer) database. Findings: TP53 was the gene harboring the highest frequency of mutations. Subsequently, 5 lethal features including TP53 mutations were screen by LASSO (Least absolute shrinkage and selector operation)-COX regression according to TP53 mutations and 22 infiltrating immune cells. And then, two distinct subgroups of HCC were identified according to previous five lethal features. What's more, the expression levels of co-inhibitory immune checkpoints were significantly up-regulated, and the GO terms or pathways to boost immune responses were found to be inhibited in immunotype B subgroup compared with that in immunotype A subgroup. Finally, the immunotype was proved to be an independent adverse prognostic factor, contribute to improving the predictive accuracy of the immunotype-based model and avoiding excessive medical treatment. Interpretation: Stratification of tumors is paramount to achieve better clinical outcomes. Herein, two distinct immunotypes of HCC in terms of prognosis, phenotype, and function were identified and subverted the traditional understanding of intratumoral CD8+ T cells. Moreover, the immunotypes contributed to improving the predictive accuracy and avoiding excessive medical treatment of some HCC patients. Funding: This study was funded by grants from the National Natural Science Foundation of China (81401988 and 81770266), the Six talent peaks project in Jiangsu Province (WSN-060) and the Key talents of youth medicine in Jiangsu Provincial Department of health (QNRC2016681). Declaration of Interest: The authors have declared that no conflicts of interest exist.

Identifying germline mutations responsible for genetic predisposition to myeloid malignancies would be useful in creating opportunities for early intervention. Recent genomic and functional studies in Shwachman-Diamond syndrome (SDS) have deciphered distinct roles for heterozygous mutations in EIF6 and TP53 in alleviating germline genetic stress and a role for biallelic TP53 mutations in malignant progression. This review has summarized evidence for a mechanistic framework underlying SDS that can potentially be applied to the study of other germline myelodysplastic syndromes (MDS) predisposition disorders.

B cell prolymphocytic leukemia is a rare and aggressive disorder often with high risk features including TP53 mutation, deletion 17p and complex karyotype. There is scarcity of data regarding treatment and existing therapies induce short lived remissions. Ibrutinib, a Bruton tyrosine kinase inhibitor, has had success in some patients with high risk features. Venetoclax, a BCL-2 inhibitor, has primarily been used in the relapsed setting. We present a case of B PLL with deletion 17p and mutated TP53 treated with ibrutinib and venetoclax in the frontline setting which resulted in measurable/minimal residual disease negative remission for approximately three years.

Many studies have shown that TP53 mutations play a negative role in antitumor immunity. However, a few studies reported that TP53 mutations could promote antitumor immunity. To explain these contradictory findings, we analyzed five cancer cohorts from The Cancer Genome Atlas (TCGA) project. We found that TP53-mutated cancers had significantly higher levels of antitumor immune signatures than TP53-wildtype cancers in breast invasive carcinoma (BRCA) and lung adenocarcinoma (LUAD). In contrast, TP53-mutated cancers had significantly lower antitumor immune signature levels than TP53-wildtype cancers in stomach adenocarcinoma (STAD), colon adenocarcinoma (COAD), and head and neck squamous cell carcinoma (HNSC). Moreover, TP53-mutated cancers were more likely to have a higher tumor mutation burden (TMB) and tumor aneuploidy level (TAL) than TP53-wildtype cancers. However, the TMB differences were more marked between TP53-mutated and TP53-wildtype cancers than the TAL differences in BRCA and LUAD, and the TAL differences were more significant in STAD and COAD. Furthermore, we showed that TMB and TAL had a positive and a negative correlation with antitumor immunity and that TMB affected antitumor immunity more than TAL did in BRCA and LUAD while TAL affected antitumor immunity more strongly than TMB in STAD and HNSC. These findings indicate that the distinct correlations between TP53 mutations and antitumor immunity in different cancer types are a consequence of the joint effect of the altered TMB and TAL caused by TP53 mutations on tumor immunity. In addition, the deregulation of p53-mediated pathways, including cell cycle and apoptosis, may also contribute to the different correlations of TP53 mutations with antitumor immunity between different cancer cohorts. Furthermore, we demonstrated the different correlations of TP53 mutations with the response to immune checkpoint inhibitors between different cancer cohorts, suggesting that the TP53 mutation status could be a useful biomarker for predicting the response to cancer immunotherapy in different cancer types.

Background: Currently, in clinical settings, all TP53 mutations have been considered equally. However, increasing evidence has triggered us to challenge such practice. Numerous studies with conflicting results have revealed the position and type of mutation have differential effects on prognosis. Such disparity can be partially attributed to the lack of unifying classification system for TP53 mutations. In this study, we compared 2 most frequently used systems, according to location or its functional effects on p53 protein, and analyzed the impact of TP53 mutations on survival in 379 advanced Chinese lung cancer patients. Methods: We performed capture-based ultra-deep targeted sequencing on plasma samples of 379 Chinese advanced lung patients. Findings: Our results show that mutations occurring in exon 8 are correlated with shorter overall survival (OS) in tyrosine kinase inhibitor (TKI)-naive (p=0.013) and previously treated with 1 line of TKI patients (p=0.032). Such mutations showed a trend of correlating with shorter OS in patients treated with 2 lines of previous treatment. The correlation between OS and TP53 mutation categorized by function or considered collectively, was not consistent across diverse treatment history. Interpretation: Our results provide solid evidence that not all TP53 mutations are equal. Exon 8 mutations can identify a subgroup of patients with unfavorable prognosis across diverse treatment history. It is the first study which compared and contrasted different TP53 mutation classification systems in a large cohort of advanced lung cancer patients. Funding Statement: This work was supported by the National Nature Science Foundation of China (81672284), and a foundation of Third Military Medical University (2012XLC08). The funders of the study have no role in study design, data analysis, data interpretation or writing of the report. Declaration of Interests: The authors declare no conflicts of interests. Ethics Approval Statement: This study was approved by the ethic committee at Chongqing Daping Hospital.

Background ROS1 fusions are found in 1% of lung cancer patients. EUCROSS is the first prospective European trial to evaluate crizotinib in this patient subset. Here we present an updated analysis of the progression-free survival (PFS), overall survival (OS) and molecular characteristics of progression. Methods Multi-centre, single arm phase II trial. Key eligibility criteria: ≥18 years of age, advanced/metastatic lung cancer, centrally confirmed ROS1-rearrangement. Treatment: 250 mg crizotinib BID. Key endpoints of this report: updated PFS (according to RECIST 1.1) and OS and molecular tumour characterization. Results Thirty patients were eligible for response evaluation (N = 30; intention-to-treat population, N = 34). Median follow-up was 44.9 months (95% CI, 39.6-47.4). At data-cut off 19 patients (63.3%) discontinued treatment due to progression or death. Investigator-assessed efficacy: ORR, 70% (95% CI, 51–85; 21/30); disease control rate, 90.0% (95% CI, 73.5-97.9; 27/30); median PFS, 19.4 months (95% CI, 10.1-31.2); 24-months-OS probability, 65.5% (95% CI, 48.3-82.9). Prevalence of co-occurring genetic aberrations by hybrid-capture sequencing was 61%. TP53 mutations were most frequent (28%; 5/18). PFS (p = 0.0219) and OS at 24 months (p = 0.015) were significantly shorter in TP53-mutant patients. Tissue or blood samples were collected in six patients at progression. In three (50%) samples, secondary mutations in ROS1 (i.e. p.G2032R (N = 2), p.L2026M (N = 1)) were detected. In one (17%), a PIK3CA mutation (p.E545K) was identified. In the other two patients (33%) aberrations of unknown significance were detected. Conclusions Updated PFS and OS results confirm the efficacy of crizotinib in ROS1-rearranged lung cancer patients. Patients with co-mutations in TP53 had significantly worse outcomes compared to TP53 wild-type patients. The most common mechanisms of resistance were mutations in ROS1. Next-generation ROS1 inhibitors or the multi-kinase inhibitor cabozantinib may be promising treatment options for these patients. Clinical trial identification NCT02183870. Legal entity responsible for the study University Hospital of Cologne. Funding Pfizer. Disclosure S. Michels: Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Bristol-Myers Squibb; Honoraria (self): Boehringer Ingelheim; Research grant / Funding (institution): Janssen; Honoraria (self): Roche. B. Massuti Sureda: Honoraria (self): Merck Sharp Dome; Honoraria (self): Boehringer Ingelheim; Honoraria (self): Roche; Honoraria (self): Pfizer. H. Schildhaus: Honoraria (self): ZytoVision; Honoraria (self): Pfizer; Honoraria (self), Research grant / Funding (institution): Roche; Honoraria (self), Research grant / Funding (institution): Novartis. M. Sebastian: Honoraria (self): Boehringer Ingelheim; Honoraria (self): Eli Lilly; Honoraria (self): Pfizer; Honoraria (self): Roche; Honoraria (self): Novartis; Honoraria (self): AstraZeneca; Honoraria (self): Bristol-Myers Squibb; Honoraria (self): Merck Sharp Dome; Honoraria (self): Takeda; Honoraria (self): Mediolanum; Honoraria (self): AbbVie; Honoraria (self): Celgene. E. Felip: Honoraria (self): AstraZeneca; Honoraria (self): Boehringer Ingelheim; Honoraria (self): Bristol-Myers Squibb; Honoraria (self): Celgene; Honoraria (self): Eli Lilly; Honoraria (self): Guardiant; Honoraria (self): Merck Sharp Dome; Honoraria (self): Merck KGa; Honoraria (self): Novartis. M. Reck: Honoraria (self): Boehringer Ingelheim; Honoraria (self): Bristol-Myers Squibb; Honoraria (self): AstraZeneca; Honoraria (self): Abbot; Honoraria (self): Celgene; Honoraria (self): Merck Sharp Dome; Honoraria (self): Merck KGa; Honoraria (self): Novartis; Honoraria (self): Pfizer; Honoraria (self): Roche. S. Merkelbach-Bruse: Honoraria (self): Pfizer; Honoraria (self): AstraZeneca; Honoraria (self): Bristol-Myers Squibb; Honoraria (self): Roche; Honoraria (self), Research grant / Funding (institution): Novartis. L. Nogova: Honoraria (self), Research grant / Funding (institution): Pfizer; Honoraria (self), Research grant / Funding (institution): Novartis; Honoraria (self), Research grant / Funding (institution): Janssen; Honoraria (self): Boehringer Ingelheim; Honoraria (self): Roche; Honoraria (self): Celgene. J. Wolf: Honoraria (self), Research grant / Funding (institution): Novartis; Honoraria (self), Research grant / Funding (institution): Pfizer; Honoraria (self), Research grant / Funding (institution): Janssen; Honoraria (self): Boehringer Ingelheim; Honoraria (self): AstraZeneca; Honoraria (self), Research grant / Funding (institution): Bristol-Myers Squibb; Honoraria (self): Chugay; Honoraria (self): Ignyta; Honoraria (self): Eli Lilly; Honoraria (self): Merck Sharp Dome; Honoraria (self): Roche. All other authors have declared no conflicts of interest.

Background Loss-of-function mutations in genes encoding components of the homologous recombination (HR) machinery are associated with tumor sensitivity to poly (ADP-ribose) polymerase (PARP) inhibitors. In ABRAZO, the PARP inhibitor talazoparib demonstrated encouraging efficacy in gBRCA-mutated ABC, both in pts whose cancer responded to prior platinum therapy (cohort 1) and in pts who had received ≥3 prior nonplatinum chemotherapy regimens for ABC (cohort 2). Methods Baseline tumor tissue (primary or metastatic sites) from enrolled pts was sequenced using the FoundationOne CDx NGS panel. 60/84 pts (71%) in the intent-to-treat population had available tumor tissue, which could be sequenced. Mutations summarized below were known or likely pathogenic single-nucleotide variants, insertions, deletions, or rearrangements. Additional exploratory computational analyses pertinent to HR deficiency were performed, including genomic loss of heterozygosity (gLOH) and somatic-germline-zygosity assessments. Results Tumor mutations in BRCA1 and BRCA2 were detected in 29 (48%) and 28 (47%) of 60 evaluable pts (no pts exhibited mutations in both BRCA1 and BRCA2). These mutations were most commonly single-nucleotide variants (BRCA1: 12 [20%] and BRCA2: 10 [17%]) or deletions (BRCA1: 11 [18%] and BRCA2: 12 [20%]). Mutations in other genes implicated in HR were comparatively rare, with mutations in CHEK2 (2 pts), ARID1A, ATR, BARD1, BRD4, BRIP1, FANCC, and STAG2 (each in single pts) detected. In addition to BRCA1/2, genes where mutations were detected in ≥ 10% of evaluable pts included TP53 (45%) and PIK3CA (12%). TP53 mutations were more commonly observed in BRCA1-mutated than in BRCA2-mutated tumors (22/29 [76%] compared with 4/28 [14%]). Associations of genetic/genomic events with progression-free survival will be presented. Conclusions NGS of tumors from the ABRAZO study of talazoparib in patients with gBRCA-mutated ABC revealed a complex mutational landscape. Exploratory correlative analyses are ongoing and will be reported. Clinical trial identification NCT02034916. Legal entity responsible for the study Pfizer Inc. Funding Pfizer Inc. Disclosure N.C. Turner: Advisory / Consultancy, Research grant / Funding (institution): Pfizer Inc.; Advisory / Consultancy, Research grant / Funding (institution): BioMarin. A..D. Laird: Full / Part-time employment: Pfizer Inc. M.L. Telli: Advisory / Consultancy, Research grant / Funding (institution): Pfizer Inc.; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy, Research grant / Funding (institution): Tesaro; Advisory / Consultancy, Research grant / Funding (institution): PharmaMar; Advisory / Consultancy, Research grant / Funding (institution): Vertex; Research grant / Funding (institution): AbbVie; Research grant / Funding (institution): Biothera; Research grant / Funding (institution): Calithera Biosciences; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): Medivation; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): OncoSec; Research grant / Funding (institution): Sanofi. H.S. Rugo: Research grant / Funding (institution): Eisai; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): GSK; Research grant / Funding (institution), Travel / Accommodation / Expenses: Lilly; Research grant / Funding (institution): MacroGenics; Research grant / Funding (institution): Merck; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): OBI Pharma; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Plexxikon; Travel / Accommodation / Expenses: Mylan; Travel / Accommodation / Expenses: Puma; Research grant / Funding (institution): Eisai; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): GlaxoSmithKline; Research grant / Funding (institution), Travel / Accommodation / Expenses: Lilly; Research grant / Funding (institution): MacroGenics; Research grant / Funding (institution): Merck; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): OBI Pharma; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Plexxikon; Travel / Accommodation / Expenses: Mylan; Travel / Accommodation / Expenses: Puma. A. Mailliez: Honoraria (self), Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: Tesaro; Advisory / Consultancy, Research grant / Funding (institution): PharmaMar; Advisory / Consultancy: Vertex; Research grant / Funding (institution): AbbVie; Research grant / Funding (institution): Biothera; Research grant / Funding (institution): Calithera Biosciences; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): Medivation; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): OncoSec; Research grant / Funding (institution): Pfizer Inc. J. Ettl: Honoraria (institution), Advisory / Consultancy: Lilly; Advisory / Consultancy, Travel / Accommodation / Expenses: Novartis; Honoraria (self), Advisory / Consultancy, Travel / Accommodation / Expenses: Pfizer; Honoraria (institution), Advisory / Consultancy: Roche; Advisory / Consultancy: Tesaro; Advisory / Consultancy: Eisai; Research grant / Funding (institution), Travel / Accommodation / Expenses: Celgene; Honoraria (self): TEVA; Honoraria (self): AstraZeneca. J. Balmana: Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: AstraZenca; Advisory / Consultancy: Clovis; Advisory / Consultancy: Tesaro; Advisory / Consultancy: BMS; Research grant / Funding (institution), Travel / Accommodation / Expenses: PharMar. P.A. Fasching: Honoraria (self), Advisory / Consultancy: Roche; Honoraria (self), Advisory / Consultancy: Amgen; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Novartis; Honoraria (self), Advisory / Consultancy: Pfizer; Honoraria (self), Advisory / Consultancy: Celgene; Honoraria (self), Advisory / Consultancy: Puma; Honoraria (self), Advisory / Consultancy: Daiichi Sankyo; Honoraria (self), Advisory / Consultancy: Eisai; Honoraria (self), Advisory / Consultancy: Merck; Honoraria (self), Advisory / Consultancy: AstraZeneca; Honoraria (self), Advisory / Consultancy: Teva; Honoraria (self), Advisory / Consultancy: Hexal; Honoraria (institution), Speaker Bureau / Expert testimony: Myelo; Research grant / Funding (institution): BioNTech. S.A. Hurvitz: Research grant / Funding (institution): Ambryx; Research grant / Funding (institution): Amgen; Research grant / Funding (institution): Bayer; Research grant / Funding (institution): BI Pharma; Research grant / Funding (institution): Biomarin; Research grant / Funding (institution): Cascadian; Research grant / Funding (institution): Daiichi Sankyo; Research grant / Funding (institution): Dignitana; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): GSK; Research grant / Funding (institution), Travel / Accommodation / Expenses: Lilly; Research grant / Funding (institution): Macrogenics; Research grant / Funding (institution): Medivation; Research grant / Funding (institution): Merrimack; Research grant / Funding (institution), Travel / Accommodation / Expenses: Novartis; Research grant / Funding (institution), Travel / Accommodation / Expenses: OBI Pharma; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Pieris; Research grant / Funding (institution): PUMA; Research grant / Funding (institution): Roche. L.A. Albacker: Full / Part-time employment: Foundation Medicine Inc. G.M. Frampton: Full / Part-time employment: Foundation Medicine Inc. J. Chelliserry: Shareholder / Stockholder / Stock options, Full / Part-time employment: Pfizer Inc. P. Bycott: Research grant / Funding (self), Shareholder / Stockholder / Stock options, Full / Part-time employment: Pfizer Inc. U. Conte: Shareholder / Stockholder / Stock options, Full / Part-time employment: Pfizer Inc. A.M. Wardley: Honoraria (self), Advisory / Consultancy: AstraZeneca; Honoraria (self), Advisory / Consultancy: Lilly; Honoraria (self), Advisory / Consultancy: Novartis; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Roche. M.E. Robson: Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: AstraZeneca; Advisory / Consultancy: McKesson; Research grant / Funding (institution): AbbVie; Research grant / Funding (institution): BioMarin; Research grant / Funding (institution): Medivation; Research grant / Funding (institution): Myriad Genetics; Research grant / Funding (institution): Tesaro. All other authors have declared no conflicts of interest.

Background SCLC is an aggressive disease with poor prognosis. Despite initial response to chemotherapy and radiotherapy, relapse occurs in most cases. To characterize genomic changes in SCLC over the course of therapy, we explored tracking tumor mutations in cell-free DNA (cfDNA) across post-treatment blood draws and comparing them to pre-treatment plasma and tissue profiles. Methods We retrospectively evaluated 235 samples collected from 24 subjects with late stage SCLC treated with first-line chemotherapy or chemoradiation in a prospective observational study. Tumor tissue samples were analyzed with the AVENIO Tumor Tissue Surveillance Kit (For Research Use Only, not for use in diagnostic procedures), a 198-kb next-generation sequencing panel covering 197 cancer genes. Matched peripheral blood mononuclear cells (PBMC), pre-treatment plasma, and multiple plasma from post-treatment timepoints were analyzed with the same panel using the AVENIO ctDNA Surveillance Kit (For Research Use Only, not for use in diagnostic procedures). A median input amount of 29 ng cfDNA, 129 ng tumor tissue DNA, and 50 ng PBMC DNA were sequenced to median deduplicated depths of 4491, 1315, and 6512, respectively. Somatic single nucleotide variants (SNVs) in tissue and plasma were identified by removing PBMC-matched germline or clonal hematopoietic mutations. Results We detected a median of 4 SNVs in tissue samples and a median of 100% (range 66 - 100%) of tissue SNVs in matched pre-treatment plasma. 96% (23/24) of subjects had at least one shared SNV between tissue and plasma, most commonly a TP53 mutation. A median of 7 SNVs were detected in pre-treatment plasma, whereas across all available post-treatment plasma (range 2 - 20 time points per subject), a median of 4 SNVs were detected. 53% of these mutations were not present in pre-treatment plasma or tissue. Conclusions Somatic mutations found in pre-treatment plasma were concordant with matched tissue, consistent with the highly metastatic nature of SCLC. ctDNA sequencing can provide additional molecular insights; in particular, detecting emergent mutations in ctDNA during treatment could advance our knowledge of SCLC. Legal entity responsible for the study Roche Sequencing Solutions, Inc. Funding Roche Sequencing Solutions, Inc. Disclosure S. Yaung: Full / Part-time employment: Roche. C. Woestmann: Full / Part-time employment: Roche. L. Xi: Full / Part-time employment: Roche. C. Ju: Full / Part-time employment: Roche. B. Hinzmann: Shareholder / Stockholder / Stock options, Full / Part-time employment: Roche. M. Thomas: Honoraria (institution), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Roche. F. Lasitschka: Research grant / Funding (institution): Roche. M. Meister: Research grant / Funding (institution): Roche. M. Schneider: Research grant / Funding (institution): Roche. F.J.F. Herth: Honoraria (institution): Roche. T. Muley: Research grant / Funding (institution), Licensing / Royalties: Roche. B. Wehnl: Full / Part-time employment: Roche. J. Palma: Shareholder / Stockholder / Stock options, Full / Part-time employment: Roche. X.M. Ma: Shareholder / Stockholder / Stock options, Licensing / Royalties, Full / Part-time employment: Roche.

Summary Background Survival of metastatic colon cancer (mCC) patients has considerably improved with optimization of new drugs regimen. Inactivation of TP53 pathway by TP53 mutations is observed in nearly half of colorectal tumors. The impact of such mutations has been poorly studied in the metastatic setting. Methods The files of 254 mCC treated in a single institution at Saint-Louis hospital between January 1999 and April 2011 were retrospectively reviewed. Tissue samples for analysis of TP53 mutations were available for 68 patients, performed using FASAY. The prognostic value of TP53 status was evaluated by comparing progression free survival (PFS) and overall survival (OS) in the group of TP53-mutated and wild type patients. Results PFS was 6.9 months and OS 21.7 months in the whole population. There was no statistical difference in TP53- mutated and wild type groups in term of PFS (HR = 1.04; IC9 5% = 0.6–1.79) and OS (HR = 0.99; IC 95% = 0.53–1.55) whatever the chemotherapy regimen (oxaliplatin- or irinotecan-based). Only BRAF V600 mutation was demonstrated to be a poor prognostic factor for PFS and OS, and CEA level for OS. Conclusions Routine determination of TP53 mutations, even with a highly sensitive method, cannot be recommended to predict chemotherapy response in mCC.