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A gastric cancer PDX model carrying two LOF mutations in the ATM gene is not responsive to olaparib.

Molecular, histological and pathological features of the 57 metastatic gastric cancer patients included in the retrospective analysis

Supplementary Methods

Mutations; Gastric cancers; PARP inhibitors Mutacions; Càncers gàstrics; Inhibidors de PARP Mutaciones; Cánceres gástricos; Inhibidores de PARP Despite negative results of clinical trials conducted on the overall population of patients with gastric cancer, PARP inhibitor (PARPi) therapeutic strategy still might represent a window of opportunity for a subpopulation of patients with gastric cancer. An estimated 7% to 12% of gastric cancers exhibit a mutational signature associated with homologous recombination (HR) failure, suggesting that these patients could potentially benefit from PARPis. To analyze responsiveness of gastric cancer to PARPi, we exploited a gastroesophageal adenocarcinoma (GEA) platform of patient-derived xenografts (PDX) and PDX-derived primary cells and selected 10 PDXs with loss-of-function mutations in HR pathway genes. Cell viability assays and preclinical trials showed that olaparib treatment was effective in PDXs harboring BRCA2 germline mutations and somatic inactivation of the second allele. Olaparib responsive tumors were sensitive to oxaliplatin as well. Evaluation of HR deficiency (HRD) and mutational signatures efficiently stratified responder and nonresponder PDXs. A retrospective analysis on 57 patients with GEA showed that BRCA2 inactivating variants were associated with longer progression-free survival upon platinum-based regimens. Five of 7 patients with BRCA2 germline mutations carried the p.K3326* variant, classified as “benign.” However, familial history of cancer, the absence of RAD51 foci in tumor cells, and a high HRD score suggest a deleterious effect of this mutation in gastric cancer. In conclusion, PARPis could represent an effective therapeutic option for BRCA2-mutated and/or high HRD score patients with GEA, including patients with familial intestinal gastric cancer. This work was funded by the Italian Association for Cancer Research (AIRC), IG 20210 and IG 27531 to S. Giordano; IG 23624 to F. Pietrantonio; IG 21770 to S. Corso. FPRC 5×1000 2015 Min. Salute “Strategy” to SG; Fondazione Piemontese per la Ricerca sul Cancro (FPRC) 5×1000 MS2017 PTCRC-intra 2020 to S. Giordano; Ricerca Locale Dept. Oncology 2021 to S. Corso; Italian Ministry of Health-Ricerca Corrente 2022–23. B. Pellegrino was supported by ESMO with a Clinical Translational Fellowship aid supported by Roche and received research grants from GOIRC. Fondazione CR Firenze to M. Benelli.

Despite negative results of clinical trials conducted on the overall population of patients with gastric cancer, PARP inhibitor (PARPi) therapeutic strategy still might represent a window of opportunity for a subpopulation of patients with gastric cancer. An estimated 7% to 12% of gastric cancers exhibit a mutational signature associated with homologous recombination (HR) failure, suggesting that these patients could potentially benefit from PARPis. To analyze responsiveness of gastric cancer to PARPi, we exploited a gastroesophageal adenocarcinoma (GEA) platform of patient-derived xenografts (PDX) and PDX-derived primary cells and selected 10 PDXs with loss-of-function mutations in HR pathway genes. Cell viability assays and preclinical trials showed that olaparib treatment was effective in PDXs harboring BRCA2 germline mutations and somatic inactivation of the second allele. Olaparib responsive tumors were sensitive to oxaliplatin as well. Evaluation of HR deficiency (HRD) and mutational signatures efficiently stratified responder and nonresponder PDXs. A retrospective analysis on 57 patients with GEA showed that BRCA2 inactivating variants were associated with longer progression-free survival upon platinum-based regimens. Five of 7 patients with BRCA2 germline mutations carried the p.K3326* variant, classified as “benign.” However, familial history of cancer, the absence of RAD51 foci in tumor cells, and a high HRD score suggest a deleterious effect of this mutation in gastric cancer. In conclusion, PARPis could represent an effective therapeutic option for BRCA2-mutated and/or high HRD score patients with GEA, including patients with familial intestinal gastric cancer.Significance:PARP inhibition is a potential strategy for treating patients with gastric cancer with mutated BRCA2 or homologous repair deficiency, including patients with familial intestinal gastric cancer, for whom BRCA2 germline testing should be recommended.

Supplementary Figure 4_Revised

Western blot analysis was performed to determine the effect of trastuzumab after 24h of treatment in N87-TR cells and their control cell line.

Top differentially regulated coding genes in N87-TR1, N87-TR2, N87-TR3, and N87-TR4 trastuzumab-resistant gastric cancer cell lines compared with NCI-N87 control cell line.

Supplementary Materials and Methods

Supplementary Table 1

Purpose:Gastric and gastroesophageal adenocarcinomas represent the third leading cause of cancer mortality worldwide. Despite significant therapeutic improvement, the outcome of patients with advanced gastroesophageal adenocarcinoma is poor. Randomized clinical trials failed to show a significant survival benefit in molecularly unselected patients with advanced gastroesophageal adenocarcinoma treated with anti-EGFR agents.Experimental Design:We performed analyses on four cohorts: IRCC (570 patients), Foundation Medicine, Inc. (9,397 patients), COG (214 patients), and the Fondazione IRCCS Istituto Nazionale dei Tumori (206 patients). Preclinical trials were conducted in patient-derived xenografts (PDX).Results:The analysis of different gastroesophageal adenocarcinoma patient cohorts suggests that EGFR amplification drives aggressive behavior and poor prognosis. We also observed that EGFR inhibitors are active in patients with EGFR copy-number gain and that coamplification of other receptor tyrosine kinases or KRAS is associated with worse response. Preclinical trials performed on EGFR-amplified gastroesophageal adenocarcinoma PDX models revealed that the combination of an EGFR mAb and an EGFR tyrosine kinase inhibitor (TKI) was more effective than each monotherapy and resulted in a deeper and durable response. In a highly EGFR-amplified nonresponding PDX, where resistance to EGFR drugs was due to inactivation of the TSC2 tumor suppressor, cotreatment with the mTOR inhibitor everolimus restored sensitivity to EGFR inhibition.Conclusions:This study underscores EGFR as a potential therapeutic target in gastric cancer and identifies the combination of an EGFR TKI and a mAb as an effective therapeutic approach. Finally, it recognizes mTOR pathway activation as a novel mechanism of primary resistance that can be overcome by the combination of EGFR and mTOR inhibitors.See related commentary by Openshaw et al., p. 2964

Purpose: hERG1 channels are aberrantly expressed in several types of human cancers, where they affect different aspects of cancer cell behavior. A thorough analysis of the functional role and clinical significance of hERG1 channels in gastric cancer is still lacking.Experimental Design: hERG1 expression was tested in a wide (508 samples) Italian cohort of surgically resected patients with gastric cancer, by immunohistochemistry and real-time quantitative PCR. The functional link between hERG1 and the VEGF-A was studied in different gastric cancer cell lines. The effects of hERG1 and VEGF-A inhibition were evaluated in vivo in xenograft mouse models.Results: hERG1 was positive in 69% of the patients and positivity correlated with Lauren's intestinal type, fundus localization of the tumor, G1–G2 grading, I and II tumor—node—metastasis stage, and VEGF-A expression. hERG1 activity modulated VEGF-A secretion, through an AKT-dependent regulation of the transcriptional activity of the hypoxia inducible factor. Treatment of immunodeficient mice xenografted with human gastric cancer cells, with a combination of hERG1 blockers and anti-VEGF-A antibodies, impaired tumor growth more than single-drug treatments.Conclusion: Our results show that hERG1 (i) is aberrantly expressed in human gastric cancer since its early stages; (ii) drives an intracellular pathway leading to VEGF-A secretion; (iii) can be exploited to identify a gastric cancer patients' group where a combined treatment with antiangiogenic drugs and noncardiotoxic hERG1 inhibitors could be proposed. Clin Cancer Res; 20(6); 1502–12. ©2014 AACR.

Purpose: The majority of gastric cancer patients who achieve an initial response to trastuzumab-based regimens develop resistance within 1 year of treatment. This study was aimed at identifying the molecular mechanisms responsible for resistance.Experimental Design: A HER2+-trastuzumab sensitive NCI-N87 gastric cancer orthotopic nude mouse model was treated with trastuzumab until resistance emerged. Differentially expressed transcripts between trastuzumab-resistant and sensitive gastric cancer cell lines were annotated for functional interrelatedness by Ingenuity Pathway Analysis software. Immunohistochemical analyses were performed in pretreatment versus posttreatment biopsies from gastric cancer patients receiving trastuzumab-based treatments. All statistical tests were two-sided.Results: Four NCI-N87 trastuzumab-resistant (N87-TR) cell lines were established. Microarray analysis showed HER2 downregulation, induction of epithelial-to-mesenchymal transition, and indicated fibroblast growth factor receptor 3 (FGFR3) as one of the top upregulated genes in N87-TR cell lines. In vitro, N87-TR cell lines demonstrated a higher sensitivity than did trastuzumab-sensitive parental cells to the FGFR3 inhibitor dovitinib, which reduced expression of pAKT, ZEB1, and cell migration. Oral dovitinib significantly (P = 0.0006) reduced tumor burden and prolonged mice survival duration in N87-TR mouse models. A higher expression of FGFR3, phosphorylated AKT, and ZEB1 were observed in biopsies from patients progressing under trastuzumab-based therapies if compared with matched pretreatment biopsies.Conclusions: This study identified the FGFR3/AKT axis as an escape pathway responsible for trastuzumab resistance in gastric cancer, thus indicating the inhibition of FGFR3 as a potential strategy to modulate this resistance. Clin Cancer Res; 22(24); 6164–75. ©2016 AACR.

PDF file - 738K, ADDITIONAL MATERIALS AND METHODS, FIGURES AND TABLES Fig S1- Immunohistochemical detection of hERG1 protein in GC specimens. Fig S2- hERG1 protein expression in GC primary samples. Figure S3- hERG1b characterization in primary GC. Fig S4- hERG1 protein expression in GC cell lines. Fig S5- hERG1USO protein expression in GC cell lines. Fig S6- Effects of the PI3K/Akt inhibition on VEGF-A secretion in AKG cells under normoxic conditions. Fig S7- Immunohistochemical detection of hERG1 protein in GC specimens. Fig S8- Immunohistochemical detection of hERG1 protein in GC specimens. Fig S9- VEGF-A and hERG1 expression in GC samples. Fig S10. Interaction analyses on OS between hERG1 and other clinical and pathological parameters (Forest Plot). Fig S11- Comparison between herg1a mRNA and hERG1A protein expression in GC samples. Table S1- Antibodies used for IHC experiments described in the main text. Table S2- Primer Sequences. Primers were used for methylation analysis and RQ-PCR. Table S3- Cell lines used in the experiments described in the main text. Table S4- hERG1 expression in AKG cells treated with alpha-hERG1 siRNAs and WAY hERG1 blocker. Table S5- VEGF-A and Kv 1.3 expression in AKG cells treated with alpha-hERG1 siRNAs, WAY hERG1 blocker and alpha-vegf-a siRNA. Table S6- Characteristics of patients excluded and included into the statistical analyses and distributions of clinical and pathological variables after multiple imputation of missing values.

The management of the primary tumor in metastatic colorectal, gastric and pancreatic cancer patients may be challenging. Indeed, primary tumor progression could be associated with severe symptoms, compromising the quality of life and the feasibility of effective systemic therapy, and might result in life-threatening complications. While retrospective series have suggested that surgery on the primary tumor may confer a survival advantage even in asymptomatic patients, randomized trials seem not to definitively support this hypothesis. We discuss the evidence for and against primary tumor resection for patients with metastatic gastrointestinal (colorectal, gastric and pancreatic) cancers treated with systemic therapies and put in context the pros and cons of the onco-surgical approach in the time of precision oncology. We also evaluate current ongoing trials on this topic, anticipating how these will influence both research and everyday practice.

Gastric cancer; Metastasectomy; Oligometastasis Cáncer gástrico; Metastasectomía; Oligometástasis Càncer gàstric; Metastasectomia; Oligometàstasi Background Local treatment improves the outcomes for oligometastatic disease (OMD, i.e. an intermediate state between locoregional and widespread disseminated disease). However, consensus about the definition, diagnosis and treatment of oligometastatic oesophagogastric cancer is lacking. The aim of this study was to develop a multidisciplinary European consensus statement on the definition, diagnosis and treatment of oligometastatic oesophagogastric cancer. Methods In total, 65 specialists in the multidisciplinary treatment for oesophagogastric cancer from 49 expert centres across 16 European countries were requested to participate in this Delphi study. The consensus finding process consisted of a starting meeting, 2 online Delphi questionnaire rounds and an online consensus meeting. Input for Delphi questionnaires consisted of (1) a systematic review on definitions of oligometastatic oesophagogastric cancer and (2) a discussion of real-life clinical cases by multidisciplinary teams. Experts were asked to score each statement on a 5-point Likert scale. The agreement was scored to be either absent/poor (2 years, either upfront local treatment or systemic treatment followed by restaging was considered as treatment (fair agreement). Conclusion The OMEC project has resulted in a multidisciplinary European consensus statement for the definition, diagnosis and treatment of oligometastatic oesophagogastric adenocarcinoma and squamous cell cancer. This can be used to standardise inclusion criteria for future clinical trials.

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has gained increasing acceptance in clinical practice. Performing CRS and HIPEC laparoscopically represents a challenging and intriguing technical evolution. However, the experiences are limited, and the evidence is low. This retrospective analysis was performed on patients treated with laparoscopic CRS-HIPEC within the Italian Peritoneal Surface Malignancies Oncoteam. Clinical, perioperative, and follow-up data were extracted and collected on prospectively maintained databases. We added a systematic review according to the PRISMA method for English-language articles through April 2022 using the keywords laparoscopic, hyperthermic, HIPEC, and chemotherapy. From 2016 to 2022, fourteen patients were treated with Lap-CRS-HIPEC with curative intent within the Italian centers. No conversion to open was observed. The median duration of surgery was 487.5 min. The median Peritoneal Cancer Index (PCI) was 3, and complete cytoreduction was achieved in all patients. Two patients (14.3%) had major postoperative complications, one requiring reintervention. After a median follow-up of 16.9 months, eleven patients were alive without disease (78.6%), two patients developed recurrence (14.3%), and one patient died for unrelated causes (7.1%). The literature review confirmed these results. In conclusion, current evidence shows that Lap-CRS-HIPEC is feasible, safe, and associated with a favorable outcome in selected patients. An accurate patient selection will continue to be paramount in choosing this treatment.

Introduction. RCTs support neoadjuvant chemoradiotherapy (nCRT) followed by surgery in Locally Advanced Esophago-Gastric Junction (LA-EGJ) adenocarcinoma. However, RCTs are performed in highly controlled settings with limited representativeness of real-life patients (RLS). Aim: To compare the outcomes in RLS and clinical trial settings. Methods. The outcomes of RLS, which comprised 125 patients consequently treated for LA-EGJ adenocarcinoma between 2012 and 2017, were compared with the phase II trial (PIIS), performed on 65 patients from 2003 to 2011. Results. About half of RLS (51.2%) were treated with nCRT according to VR-protocol, 20.8% with standard-CRT according to CROSS/Al-Sarraf, 20% with CT alone. pCR was 36.8%, 28.6% and 9.1% after VR-protocol, standard-CRT, and chemotherapy respectively (p=0.082), while three-year overall survival (OS) was 58.6% (95% CI 43.2-71.1%), 32.8% (14.6-52.4%) and 44.8% (21.3-65.9%) respectively (p=0.030). With respect to PIIS, RLS had a higher proportion of cN+ (94% versus 54%; p

Background In several reports, gastric cancer nomograms for predicting overall or disease‐specific survival have been described. The American Joint Committee on Cancer (AJCC) introduced the attractiveness of disease‐specific mortality (DSM) as an endpoint of risk model. This study aimed to develop the first pretreatment gastric cancer nomogram for predicting DSM that considers competing risks (CRs). Methods The prediction model was developed using data for 5231 gastric cancer patients. Fifteen prognosticators, which were registered at diagnosis, were evaluated. The nomogram for DSM was created as visualizations of the multivariable Fine and Gray regression model. An independent cohort for external validation consisted of 389 gastric cancer patients from a different institution. The performance of the model was assessed by discrimination (Harrell's concordance (C)‐index), calibration, and decision curve analysis. DSM and CRs were evaluated, paying special attention to host‐related factors such as age and Eastern Cooperative Oncology Group performance status (ECOG PS), by using Gray's univariable method. Results Fourteen prognostic factors were selected to develop the nomogram. The new nomogram for DSM exhibited good discrimination. Its C‐index of 0.887 surpassed that of the American Joint Committee on Cancer (AJCC) clinical staging (0.794). The C‐index was 0.713 (AJCC, 0.582) for the external validation cohort. The nomogram showed good performance internally and externally, in the calibration and decision curve analysis. Host‐related factors including age and ECOG PS, were strongly correlated with competing risks. Conclusions The newly developed nomogram accurately predicts DSM, which can be used for patient counseling in clinical practice., The newly developed gastric cancer nomogram for disease‐specific mortality accurately predicts treatment outcomes and thereby improve risk stratification and patient selection for routine clinical decision‐making and future clinical trials. This model will improve on the traditional categorical AJCC system in the future.

Mixed neuroendocrine/non-neuroendocrine neoplasms (MiNEN) are rare mixed epithelial neoplasms in which a neuroendocrine component is combined with a non-neuroendocrine component. Here, we provide the clinical, pathologic, and molecular report of a 73-year-old-man presenting with an intestinal MiNEN. The lesion was composed of a well-differentiated G3 neuroendocrine tumor and a colloid adenocarcinoma. The molecular characterization was performed using a multigene next-generation sequencing panel. The neoplasm displayed microsatellite instability due to MLH1 promoter methylation. The extended molecular profile documented the same mutations affecting ARID1A, ASXL1, BLM, and RNF43 genes in both components, indicating a monoclonal origin of the tumor. Regarding component-specific gene mutations, BRCA2 was specifically altered in the neuroendocrine area. It may represent a new actionable target for precision oncology in MiNEN, but the lack of its alteration in the colloid component calls for further considerations on intratumor heterogeneity. The most important finding with potential immediate implications regards the presence of microsatellite instability: it indicates that this molecular alteration should become part of the diagnostic algorithm for these rare neoplasms.

In a previous study on esophageal adenocarcinoma (EAC) cases submitted to surgery (without neoadjuvant treatment), an algorithm (EACGSE classification) 1 based on morphologic distinctions provided significant prognostic impact. Tumor budding is a specific type of invasive growth pattern and was found to be an important prognostic parameter in gastrointestinal cancers. 2–3 We aimed to evaluate the prevalence of budding in glandular adenocarcinomas and its impact on survival. The EAC cohort classified according to EACGSE 1 was included in the study: among the different histotypes, 215 cases, classified as well (WD) and poorly (PD) differentiated glandular adenocarcinomas, were considered. Tumor budding was defined as single cells or clusters of up to four cells at the invasive margin. Budding was grouped according to ITBCC 2 into Bd1 (0-4 buds), Bd2 (5-9 buds), and Bd3 (10 or more buds). Furthermore, the most prognostically relevant cut off for bud number in EAC was defined by ROC analysis. Cancer specific survival analyses were performed using the Kaplan–Meier method and Cox regression analyses. Tumor budding was assessed in one hotspot (a field measuring 0.785 mm2) at the invasive front and ROC analysis identified 8 buds per field cut off as the most informative in relation to survival. By using this cut off, frequency of budding was higher in glandular PD (84/124,68%) cases than in WD ones (7/91,8%, p Tumor budding showed a prognostically negative impact in glandular EACs. The 8 buds per field cut off appears to provide the best prognostic discriminant. Tumor budding assessment should be added to the identification of other prognostic factors already described in the same series (stage, histotype and vascular invasion). 1

The incidence of esophageal adenocarcinoma (EAC) has constantly risen in western countries over the past decades, often diagnosed at advanced stage and with a five-year survival around 20%1. In a previous study on EAC cases submitted to surgery (without neoadjuvant treatment) an algorithm (EACGSE classification)2 based on morphologic distinctions provided a significant prognostic impact. We aimed to evaluate the molecular basis underlying these differences, to improve patient management. The EAC cohort classified according to EACGSE2 was included in the study. Genomic DNA was available from formalin fixed paraffin embedded surgical specimens for 207 cases. The cases were sequenced for 26 cancer-related genes (panel #226722257; IDT) with high coverage on NextSeq500 (Illumina). Data analysis was performed using a dedicated pipeline3. 245 cases were analyzed for SMAD4 immunostaining (IHC). Loss of SMAD4 immunostaining was reported as % of negative tumor cells (at least 35% of neoplastic cells). TP53 was the most frequently altered gene (134/207 cases with at least one mutation). The presence of TP53 missense variants was associated to a poor cancer-specific survival (CSS) in the high-risk cases (glandular poorly differentiated, mucinous invasive, diffuse anaplastic, mixed) according to EACGSE2 (P=0.0005). A significant correlation was observed for TP53 truncative variants and loss of SMAD4 staining (P=0.008). Actually, SMAD4 loss was observed in 85/245 (35%) of all EAC cases analyzed via immunostaining. SMAD4 loss correlated with poor CCS (P=0.007) and disease-free survival (P=0.002) in EACGSE high-risk cases. TP53 missense mutations correlated to poor outcomes (CSS) in high-risk cases, TP53 truncative mutations were associated to SMAD4 loss. SMAD4 loss itself resulted a frequent event in EAC and correlated with lower CCS and disease-free survival in high-risk cases. Therefore, we were able to correlate EAC histological classification, clinical outcomes and molecular phenotypes. Validation in independent samples is warranted to corroborate these findings. References 1. Coleman et al. Gastroenterology2018;154:390–405. 2. Fiocca et al. Cancers 2021;13:5211. 3. Isidori et al. CTG 202011:e00202.

The incidence of esophagogastric junctional adenocarcinoma (EGJ) has been steadily increasing over the last 30 years, especially in Western countries. Surgical and oncological treatment of these malignancies are still debated, in particular in case of true junctional cancer (Siewert type II tumors). The aim of the study is to compare different approaches to EGJ cancers in high volume centers around the world. We administered a survey to 39 international opinion leaders, working in high volume centers, with a minimum of 50 gastrectomies and 20 esophagectomies performed as first operator. The survey was structured in the form of clinical case scenarios, created to focus on different peculiar issues in the management of Siewert type II tumors. The main fields of investigation were the oncological approach of these malignancies (i.e. choice and type of neoadjuvant treatment) and the preferred surgical strategy. Our first finding was that almost 80% of responders would choose a neoadjuvant treatment even in cT2N0 patients, fearing probably the low accuracy of the clinical staging. Secondly, 60% of surgeons would prefer chemotherapy over chemoradiotherapy in locally advanced Siewert II tumors, regardless of histological subtype and nodal diffusion. As for the surgical strategy, we reported a strong preference (75% of responders) for two-field esophagectomy, over three-field esophagectomy (11%) and total extended gastrectomy (14%). However, in case of signet-ring cell carcinoma, up to 20% of surgeons would prefer an extended total gastrectomy, to avoid a distal positive margin. Our survey confirms that the management of Siewert type II tumors is greatly debated, even among experts of the field, and it needs to be tailored on the patient and tumor characteristics. Even so, we observed a trend towards the choice of chemo over chemoradiotherapy for any histological subtype. When operating on Siewert type II tumors, a thoracic approach is considered necessary by most of responders.

Background: Delayed gastric emptying (DGE) is a common complication after esophagectomy with gastric tube reconstruction. It is still unclear whether a pyloric drainage procedure might reduce the r...

Poorly cohesive (PC) gastric cancer (GC) exhibits variable clinical behavior, being extremely aggressive in most cases but more indolent at times. We hypothesized that the integrative genomic and gene expression characterization of a PC GC series could help identifying molecular subtypes with potential clinical implications.64 PC GCs were assessed for alterations in 409 genes and 30 cases were subjected to transcriptomic profiling of 20,815 genes.A median of 8.2 mutations per Mb (interquartile range 6.9-10.4) was found and a tumor mutational load10 muts/Mb was significantly associated with patients' worse survival ( P =0.0024). The most frequent mutated genes were CDH1 and TP53 (each 32.8%) followed by PIK3CA (10.9%). In 15 samples (23.4%), at least 1 chromatin remodeling gene was mutated: KMT2D (5 cases); ARID1A and BAP1 (4 cases each); EZH2 , KMT2A , PBRM1 (1 case each). Eight samples (12.5%) had fusion genes involving CLDN18 gene. Gene expression profiling identified 4 different clusters: cluster A associated with epithelial to mesenchymal transition (EMT) signature; cluster B associated to proliferative signature and EMT; cluster C correlated to hedgehog signaling; cluster D showing no enrichment for any of the previous signatures. Notably, cluster A and B showed a worse prognosis compared with clusters C and D ( P =0.0095).integrated genomic and transcriptomic analysis suggest the existence of 4 molecular subtypes of PC GC with prognostic significance where EMT features are associated with a worse outcome.

Optimal surgical treatment for Siewert type II esophagogastric junction adenocarcinoma is debated. The aim of this study was to compare transhiatal extended gastrectomy (TEG) and transthoracic esophagectomy (TTE). Patients with Siewert type II tumors who underwent a resection by TEG or TTE in two centers (Erasmus University Medical Center, Rotterdam, and University of Verona) between 2014 and 2019 were identified. To limit selection bias, patients were matched for baseline characteristics and compared with a multivariable logistic regression model. Some 159 patients treated by TEG (60 patients, 37.7%) or TTE (99 patients, 62.3%) were included. Patients in the TEG group were older, had less tumor invasion of the esophagus, and were more often excluded from neoadjuvant therapy. Post-operative morbidity was comparable (P = 0.88), while 90-day mortality was higher after TEG (90-day mortality 10.0% in TEG group vs. 2.0% in TTE group P = 0.01). R0 resection was achieved in 83.3% of patients after TEG and in 97.9% after TTE (P

Background Data on ERAS for gastrectomy are scarce, and the majority of the studies come from Eastern countries. Patients in the West are older and suffer from more advanced tumors that impair their clinical condition and often require neoadjuvant treatment. This retrospective study assessed the feasibility and safety of an Enhanced Recovery After Surgery (ERAS) protocol for gastrectomy in a Western center. Methods We conducted a single-center study of 351 patients operated for gastric cancer: 103, operated from January 2015 to December 2016, followed the standard pathway, while 248, operated from January 2017 to December 2019, followed the ERAS program. The primary outcomes considered were length of hospital stay (LOS) and direct costs. Secondary outcomes were 90-day morbidity and mortality, readmission rate, and compliance with ERAS items. A propensity score (PS) was built on confounding variables. Results Compliance with ERAS items after the program was ≥ 70%. Univariable analysis evidenced a 2-day median reduction in LOS and a median cost reduction of €826 per patient in the ERAS group. PS-based multivariable analysis confirmed a significant, 2-day decrease in median LOS and a €1097 saving after ERAS introduction. Ninety-day mortality decreased slightly in ERAS group, while complications and readmissions did not change significantly. When complications were included in the multivariable analysis, ERAS retained its significance, although the effects on LOS and cost were blunted to a median reduction of 1 day and €775, respectively. Conclusions ERAS for gastrectomy improved patients’ recovery and reduced hospital costs without changes in morbidity, mortality, or readmission.

Purpose: Gastric and gastroesophageal adenocarcinomas represent the third leading cause of cancer mortality worldwide. Despite significant therapeutic improvement, the outcome of patients with advanced gastroesophageal adenocarcinoma is poor. Randomized clinical trials failed to show a significant survival benefit in molecularly unselected patients with advanced gastroesophageal adenocarcinoma treated with anti-EGFR agents. Experimental Design: We performed analyses on four cohorts: IRCC (570 patients), Foundation Medicine, Inc. (9,397 patients), COG (214 patients), and the Fondazione IRCCS Istituto Nazionale dei Tumori (206 patients). Preclinical trials were conducted in patient-derived xenografts (PDX). Results: The analysis of different gastroesophageal adenocarcinoma patient cohorts suggests that EGFR amplification drives aggressive behavior and poor prognosis. We also observed that EGFR inhibitors are active in patients with EGFR copy-number gain and that coamplification of other receptor tyrosine kinases or KRAS is associated with worse response. Preclinical trials performed on EGFR-amplified gastroesophageal adenocarcinoma PDX models revealed that the combination of an EGFR mAb and an EGFR tyrosine kinase inhibitor (TKI) was more effective than each monotherapy and resulted in a deeper and durable response. In a highly EGFR-amplified nonresponding PDX, where resistance to EGFR drugs was due to inactivation of the TSC2 tumor suppressor, cotreatment with the mTOR inhibitor everolimus restored sensitivity to EGFR inhibition. Conclusions: This study underscores EGFR as a potential therapeutic target in gastric cancer and identifies the combination of an EGFR TKI and a mAb as an effective therapeutic approach. Finally, it recognizes mTOR pathway activation as a novel mechanism of primary resistance that can be overcome by the combination of EGFR and mTOR inhibitors. See related commentary by Openshaw et al., p. 2964

Summary Hepatoid tumors (HT) are rare neoplasms morphologically resembling hepatocellular carcinoma, which arise in several organs other than the liver. A comprehensive molecular profile of this group of neoplasms is still lacking. Genomic characterization of 19 HTs from different organs (three colon HTs, four esophagogastric HTs, four biliary HTs, six genitourinary HTs, two lung HTs) was performed using a multigene next-generation sequencing panel. NGS unraveled a composite molecular profile of HT. Their genetic alterations were clearly clustered by tumor site: (i) colorectal HT displayed microsatellite instability, high tumor mutational burden, mutations in ARID1A/B genes and NCOA4-RET gene fusion (2/3 cases); (ii) gastric HT had TP53 mutations (2/4); (iii) biliary HT displayed loss of CDKN2A (3/4) and loss of chromosome 18 (2/4); (iv) genital HT showed gain of chromosome 12 (3/6); (v) lung HT had STK11 somatic mutations (2/2). The only commonly mutated gene occurring in HT of different sites was TP53 (8/19 cases: colon 2, esophagogastric 2, biliary 2, genital 1, lungs 1). This study shows that most genetic alterations of HT were clustered by site, indicating that context matters. The novel potential targets for HT precision oncology are also clustered based on the anatomic origin. This study shed light on the biology of these rare cancers and may have important consequences for treatment decisions and clinical trial selection for HT patients.

Italian Research Group for Gastric Cancer (GIRCG), during the 2013 annual Consensus Conference to gastric cancer, stated that laparoscopic or robotic approach should be limited only to early gastric cancer (EGC) and no further guidelines were currently available. However, accumulated evidences, mainly from eastern experiences, have supported the application of minimally invasive surgery also for locally advanced gastric cancer (AGC). The aim of our study is to give a snapshot of current surgical propensity of expert Italian upper gastrointestinal surgeons in performing minimally invasive techniques for the treatment of gastric cancer in order to answer to the question if clinical practice overcome the recommendation. Experts in the field among the Italian Research Group for Gastric Cancer (GIRCG) were invited to join a web 30-item survey through a formal e-mail from January 1st, 2020, to June 31st, 2020. Responses were collected from 46 participants out of 100 upper gastrointestinal surgeons. Percentage of surgeons choosing a minimally invasive approach to treat early and advanced gastric cancer was similar. Additionally analyzing data from the centers involved, we obtained that the percentage of minimally invasive total and partial gastrectomies in advanced cases augmented with the increase of surgical procedures performed per year (p = 0.02 and p = 0.04 respectively). It is reasonable to assume that there is a widening of indications given by the current national guideline into clinical practice. Propensity of expert Italian upper gastrointestinal surgeons was to perform minimally invasive surgery not only for early but also for advanced gastric cancer. Of interest volume activity correlated with the propensity of surgeons to select a minimally invasive approach.

Oesophageal neoplasm; Oligometastasis; Radiosurgery Neoplàsia esofàgica; Oligometàstasi; Radiocirurgia Neoplasia esofágica; Oligometástasis; Radiocirugía Background Consensus about the definition and treatment of oligometastatic oesophagogastric cancer is lacking. Objective To assess the definition and treatment of oligometastatic oesophagogastric cancer across multidisciplinary tumour boards (MDTs) in Europe. Material and methods European expert centers (n = 49) were requested to discuss 15 real-life cases in their MDT with at least a medical, surgical, and radiation oncologist present. The cases varied in terms of location and number of metastases, histology, timing of detection (i.e. synchronous versus metachronous), primary tumour treatment status, and response to systemic therapy. The primary outcome was the agreement in the definition of oligometastatic disease at diagnosis and after systemic therapy. The secondary outcome was the agreement in treatment strategies. Treatment strategies for oligometastatic disease were categorised into upfront local treatment (i.e. metastasectomy or stereotactic radiotherapy), systemic therapy followed by restaging to consider local treatment or systemic therapy alone. The agreement across MDTs was scored to be either absent/poor (

Background Pretreatment clinical staging is essential to select therapy. However, there have been no published pretreatment gastric cancer nomograms constructed using pretreatment clinical prognostic factors, including in nonresection patients. We aimed to develop a new pretreatment gastric cancer nomogram for individualized prediction of overall survival (OS). Methods The nomogram was developed using data of 5231 Japanese gastric cancer patients, and it was created with a Cox regression model. Fifteen clinical variables, which were obtained at pretreatment, were collected and registered. Data of two independent cohorts of patients from Seoul St. Mary's Hospital (1001 patients), and the University of Verona (389 patients) formed the external validation cohorts. The model was validated internally and externally using measures of discrimination (Harrell's C‐index), calibration, and decision curve analysis. Results The developed nomogram showed good discrimination, with a C‐index of 0.855; that of the American Joint Committee on Cancer (AJCC) clinical stage was 0.819. In the external validation procedure, the C‐indexes were 0.856 (AJCC, 0.795) in the Seoul St. Mary's cohort and 0.714 (AJCC, 0.648) in the University of Verona cohort. The nomogram performed well in the calibration and decision curve analyses when applied to both the internal and external validation cohorts. A stage‐specific subset survival analysis of the three risk groups calculated using the nomogram also showed the superiority of nomogram‐prediction when compared to AJCC. Conclusion This new pretreatment model accurately predicts OS in gastric cancer and can be used for patient counseling in clinical practice and stratification in clinical trials., The newly developed gastric cancer pretreatment nomogram can accurately predict overall survival and thereby improve risk stratification and patient selection for routine clinical decision‐making and future clinical trials. This model will improve on the traditional categorical AJCC system in the future.

Pseudomyxoma peritonei (PMP) is a rare condition characterized by the intraperitoneal accumulation of mucus derived mostly by appendiceal mucinous neoplasm. Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) can offer a favourable overall survival. In this study, we report a single-institute outcomes following CRS and HIPEC in patients with this condition. This is a review of prospectively collected data from 32 patients (11 men and 21 women) affected by PMP of appendiceal origin who underwent CRS and HIPEC from 2008 to 2016 in our Surgical Unit of General and Esophagogastric Surgery. The median age of the patients was 53 years (range 25—77 years). After CRS, all patients underwent HIPEC (mytomicin C 3.3 mg/m2/L and cisplatin 25 mg/m2/L at 41 °C for 60 min) with closed abdomen technique. The median (range) follow-up time for surviving patients was 43 (18–119) months. The median peritoneal cancer index (PCI) was 17. Complete cytoreductive surgery (CC0) was achieved in in 22 patients (69%). The majority of patients (88%) had grade I–II complications, 3 (9%) had grade III complications, and 1 (3%) patient had a grade IV complication. There were no perioperative mortalities. The median hospital stay was 9.5 (range 9–24) days. One year and 5-year overall survival (OS) were 90% and 58%, respectively. Regardless of histotype, disease-free survival was 95% at 1 year and 46% at 5 years. CRS in combination with HIPEC is a feasible treatment strategy and can achieve a satisfactory outcome in patients with PMP of appendiceal origin.

Gastrectomy for gastric cancer is still performed in Western countries with high morbidity and mortality. Post-operative complications are frequent, and effective diagnosis and treatment of complications is crucial to lower the mortality rates. In 2015, a project was launched by the EGCA with the aim of building an agreement on list and definitions of post-operative complications specific for gastrectomy. In 2018, the platform www.gastrodata.org was launched for collecting cases by utilizing this new complication list. In the present paper, the Italian Research Group for Gastric Cancer endorsed a collection of complicated cases in the period 2015–2019, with the aim of investigating the clinical pictures, diagnostic modalities, and treatment approaches, as well as outcome measures of patients experiencing almost one post-operative complication. Fifteen centers across Italy provided 386 cases with a total of 538 complications (mean 1.4 complication/patient). The most frequent complications were non-surgical infections (gastrointestinal, pulmonary, and urinary) and anastomotic leaks, accounting for 29.2% and 17.3% of complicated patients, with a median Clavien–Dindo score of II and IIIB, respectively. Overall mortality of this series was 12.4%, while mortality of patients with anastomotic leak was 25.4%. The clinical presentation with systemic septic signs, the timing of diagnosis, and the hospital volume were the most relevant factors influencing outcome.

Objectives Peritoneal carcinomatosis is the most frequent site of metastases in patients with gastric cancer. Current standard treatment is palliative systemic chemotherapy with very poor prognosis. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) resulted in long-term benefits in selected patients. Among patients with peritoneal carcinomatosis, a distinctive subset is oligometastatic disease which is characterized by low metastatic burden. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a recent technique of intraperitoneal chemotherapy used in combination with systemic chemotherapy with promising results. Methods PIPAC VER-One is a prospective, randomized, multicenter phase III clinical trial that aims to evaluate the effectiveness of the use of PIPAC in combination with systemic chemotherapy in patients with gastric cancer and synchronous positive peritoneal cytology and/or limited peritoneal metastases (peritoneal cancer index [PCI] ≤6). Patients will be randomized into two arms: arm A (control) treated with standard systemic chemotherapy and arm B (experimental) treated with a bidirectional scheme including PIPAC and systemic chemotherapy. Results Primary endpoint is the secondary resectability rate. Secondary endpoints are: overall survival (OS), pregression-free survival (PFS), disease-free survival (DFS), histological response assessed both on primary tumor and peritoneal lesions, quality of life (QoL), complication rate (CTCAE v5), and incremental cost-effectiveness ratios (ICER). Conclusions The role of PIPAC in multimodal treatment for oligometastatic gastric cancer will be investigated in this trial.

HIPEC is a potentially useful locoregional treatment combined with cytoreduction in patients with peritoneal colorectal metastases. Despite being widely used in several cancer centers around the world, its role had never been investigated before the results of three important RCTs appeared on this topic. The PRODIGE 7 trial clarified the role of oxaliplatin-based HIPEC in patients treated with radical surgery. Conversely, the PROPHYLOCHIP and the COLOPEC were designed to chair the role of HIPEC in patients at high risk of developing peritoneal metastases. Although all three trials demonstrated the relative ineffectiveness of HIPEC for treating or preventing peritoneal metastases, these results are not sufficient to abandon this technique. In addition to some criticisms relating to the design of the trials and their statistical value, the oxaliplatin-based HIPEC was found to be ineffective in preventing or treating peritoneal colorectal metastases, especially in patients already treated with systemic platinum-based chemotherapy. Several studies are ongoing investigating further HIPEC drugs and regimens. The review deeply discussed all the aspects and relapses of this new evidence.

Background: Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a novel intraperitoneal drug delivery method of low-dose chemotherapy as a pressurized aerosol in patients affected by peritoneal cancer of primary or secondary origin. We performed a systematic review and meta-analysis with the aim of assessing the feasibility, safety, and efficacy of PIPAC. Methods: A systematic literature search was performed using Medline and Web of Science databases from 1 January 2011, to inception, to 31 December 2021. Data were independently extracted by two authors. The Newcastle-Ottawa Scale was used to assess the quality and risk of bias of studies. Meta-analysis was performed for pathological response, radiological response, PCI variation along treatment, and for patients undergoing three or more PIPAC. Pooled analyses were performed using the Freeman–Tukey double arcsine transformation, and 95% CIs were calculated using Clopper–Pearson exact CIs in all instances. Results: A total of 414 papers on PIPAC were identified, and 53 studies considering 4719 PIPAC procedure in 1990 patients were included for analysis. The non-access rate or inability to perform PIPAC pooled rate was 4% of the procedures performed. The overall proportion of patients who completed 3 or more cycles of PIPAC was 39%. Severe toxicities considering CTCAE 3–4 were 4% (0% to 38.5%). In total, 50 studies evaluated deaths within the first 30 postoperative days. In the included 1936 patients were registered 26 deaths (1.3%). The pooled analysis of all the studies reporting a pathological response was 68% (95% CI 0.61–0.73), with an acceptable heterogeneity (I2 28.41%, p = 0.09). In total, 10 papers reported data regarding the radiological response, with high heterogeneity and a weighted means of 15% (0% to 77.8%). PCI variation along PIPAC cycles were reported in 14 studies. PCI diminished, increased, or remained stable in eight, one and five studies, respectively, with high heterogeneity at pooled analysis. Regarding survival, there was high heterogeneity. The 12-month estimated survival from first PIPAC for colorectal cancer, gastric cancer, gynecological cancer and hepatobiliary/pancreatic cancer were, respectively, 53%, 25%, 59% and 37%. Conclusions: PIPAC may be a useful treatment option for selected patients with PM, with acceptable grade 3 and 4 toxicity and promising survival benefit. Meta-analysis showed high heterogeneity of data among up-to-date available studies. In a subset analysis per primary tumor origin, pathological tumor regression was documented in 68% of the studies with acceptable heterogeneity. Pathological regression seems, therefore, a reliable outcome for PIPAC activity and a potential surrogate endpoint of treatment response. We recommend uniform selection criteria for patients entering a PIPAC program and highlight the urgent need to standardize items for PIPAC reports and datasets.

Background The present study provides a snapshot of Italian patients with peritoneal metastasis from gastric cancer treated by surgery in Italian centers belonging to the Italian Research Group on Gastric Cancer. Prognostic factors affecting survival in such cohort of patients were evaluated with the final aim to identify patients who may benefit from radical intent surgery. Methods It is a multicentric retrospective study based on a prospectively collected database including demographics, clinical, surgical, pathological, and follow-up data of patients with gastric cancer and synchronous macroscopic peritoneal metastases. Patients were surgically treated from January 2005 to January 2017. We focused on patients with macroscopic peritoneal carcinomatosis (PC) treated with upfront surgery in order to provide homogeneous evidences. Results Our results show that patients with peritoneal carcinomatosis cannot be considered all lost. Strictly selected cases (R0/R1 and P1 patients) could benefit from an aggressive surgical approach performing an extended lymphadenectomy and HIPEC treatment. Conclusion The main result of the study is that GC patients with limited peritoneal involvement can have a survival benefit from a surgery with “radical oncological intent”, that means extended lymphadenectomy and R0 resection. The retrospective nature of this study is an important bias, and for this reason, we have started a prospective multicentric study including Italian stage IV patients that hopefully will give us more answers.

D2 lymphadenectomy is currently recommended for locally advanced gastric cancer by the European guidelines. Extended D3 lymphadenectomy with para-aortic node dissection (PAND) could be indicated in the curative or prophylactic setting. In this video, PAND during open total gastrectomy is shown.