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The Society of Abdominal Radiology’s Colorectal and Anal Cancer Disease-Focused Panel (DFP) first published a rectal cancer lexicon paper in 2019. Since that time, the DFP has published revised initial staging and restaging reporting templates, and a new SAR user guide to accompany the rectal MRI synoptic report (primary staging). This lexicon update summarizes interval developments, while conforming to the original lexicon 2019 format. Emphasis is placed on primary staging, treatment response, anatomic terminology, nodal staging, and the utility of specific sequences in the MRI protocol. A discussion of primary tumor staging reviews updates on tumor morphology and its clinical significance, T1 and T3 subclassifications and their clinical implications, T4a and T4b imaging findings/definitions, terminology updates on the use of MRF over CRM, and the conundrum of the external sphincter. A parallel section on treatment response reviews the clinical significance of near-complete response and introduces the lexicon of “regrowth” versus “recurrence”. A review of relevant anatomy incorporates updated definitions and expert consensus of anatomic landmarks, including the NCCN’s new definition of rectal upper margin and sigmoid take-off. A detailed review of nodal staging is also included, with attention to tumor location relative to the dentate line and locoregional lymph node designation, a new suggested size threshold for lateral lymph nodes and their indications for use, and imaging criteria used to differentiate tumor deposits from lymph nodes. Finally, new treatment terminologies such as organ preservation, TNT, TAMIS and watch-and-wait management are introduced. This 2023 version aims to serve as a concise set of up-to-date recommendations for radiologists, and discusses terminology, classification systems, MRI and clinical staging, and the evolving concepts in diagnosis and treatment of rectal cancer. Graphical abstract

Lateral pelvic lymph node (LPLN) metastases are an important cause of preventable local failure in rectal cancer. The aim of this study was to evaluate clinical and oncological outcomes following magnetic resonance imaging (MRI)-directed surgical selection for lateral pelvic lymph node dissection (LPLND) after total neoadjuvant therapy (TNT).A retrospective consecutive cohort analysis was performed of rectal cancer patients with enlarged LPLN on pretreatment MRI. Patients were categorized as LPLND or non-LPLND. The main outcomes were lateral local recurrence rate, perioperative and oncological outcomes and factors associated with decision making for LPLND.A total of 158 patients with enlarged pretreatment LPLN and treated with TNT were identified. Median follow-up was 20 months (interquartile range 10-32). After multidisciplinary review, 88 patients (56.0%) underwent LPLND. Mean age was 53 (SD±12) years, and 54 (34.2%) were female. Total operative time (509 vs 429 minutes; P =0.003) was greater in the LPLND group, but median blood loss ( P =0.70) or rates of major morbidity (19.3% vs 17.0%) did not differ. LPLNs were pathologically positive in 34.1%. The 3-year lateral local recurrence rates (3.4% vs 4.6%; P =0.85) did not differ between groups. Patients with LPLNs demonstrating pretreatment heterogeneity and irregular margin (odds ratio, 3.82; 95% confidence interval: 1.65-8.82) or with short-axis ≥5 mm post-TNT (odds ratio 2.69; 95% confidence interval: 1.19-6.08) were more likely to undergo LPLND.For rectal cancer patients with evidence of LPLN metastasis, the appropriate selection of patients for LPLND can be facilitated by a multidisciplinary MRI-directed approach with no significant difference in perioperative or oncologic outcomes.

Knowing the sensitivity and specificity of tissue-specific immunohistochemical markers is crucial for accurate determination of the primary tumor site. PAX8 has been used as a diagnostic marker for carcinomas of the gynecologic tract, kidney, and thyroid gland, and CDX2 has been used as a marker of gastrointestinal carcinoma. Neither is considered a marker for breast carcinoma (BC). However, we have encountered BCs that express PAX8 or CDX2, some of which caused diagnostic confusion. We investigated the immunohistochemical staining frequency of PAX8 and CDX2 in BC. We identified 237 BCs for which PAX8 staining results were reported (102 primary and 135 metastatic BCs); seven primary and four metastatic BCs (4.6%) were positive for PAX8, with various intensities and staining patterns. CDX2 staining results were reported for 271 BCs (78 primary and 193 metastatic); four primary BCs and one metastatic BC (1.8%) were positive for CDX2, ranging from focal and weak to diffuse and strong. We also stained primary invasive BCs with PAX8 and CDX2 using tissue microarrays. None of the 332 PAX8-stained cases was positive, while one of 143 CDX2-stained cases was positive. Four PAX8-positive and three CDX2-positive cases were stained with TRPS1, and all were positive for TRPS1. In addition, we reviewed the literature for PAX8 and CDX2 expression in BCs and found 5.5% PAX8-positive BCs (90/1625) in 17 studies and 0.8% CDX-2 positive BCs (7/909) in 20 studies. PAX8 and CDX2 are infrequently expressed in BC by immunohistochemistry, and in rare cases, the staining can be strong and diffuse. Additional diagnostic markers are necessary and helpful in distinguishing breast from other primary origins.

Supplementary Figures S1-S5

Supplementary Figure S2. A. Proportion of VUS with different pathogenic probabilities estimated from a calibrated algorithm based on customized MAPP and Polyphen2 scores; B. Proportion of VUS per gene with different pathogenic probabilities; C. Distribution of probabilities of pathogenicity for all four MMR genes; D. MLH1; E. MSH2; F. MSH6; G. PMS2 genes.

Familial adenomatous polyposis (FAP) is a hereditary colorectal cancer syndrome, which results in the development of hundreds of adenomatous polyps carpeting the gastrointestinal tract. NSAIDs have reduced polyp burden in patients with FAP and synthetic rexinoids have demonstrated the ability to modulate cytokine-mediated inflammation and WNT signaling. This study examined the use of the combination of an NSAID (sulindac) and a rexinoid (bexarotene) as a durable approach for reducing FAP colonic polyposis to prevent colorectal cancer development. Whole transcriptomic analysis of colorectal polyps and matched normal mucosa in a cohort of patients with FAP to identify potential targets for prevention in FAP was performed. Drug-dose synergism of sulindac and bexarotene in cell lines and patient-derived organoids was assessed, and the drug combination was tested in two different mouse models. This work explored mRNA as a potential predictive serum biomarker for this combination in FAP. Overall, transcriptomic analysis revealed significant activation of inflammatory and cell proliferation pathways. A synergistic effect of sulindac (300 μmol/L) and bexarotene (40 μmol/L) was observed in FAP colonic organoids with primary targeting of polyp tissue compared with normal mucosa. This combination translated into a significant reduction in polyp development in ApcMin/+ and ApcLoxP/+-Cdx2 mice. Finally, the reported data suggest miRNA-21 could serve as a predictive serum biomarker for polyposis burden in patients with FAP. These findings support the clinical development of the combination of sulindac and bexarotene as a treatment modality for patients with FAP.Prevention Relevance:This study identified a novel chemopreventive regimen combining sulindac and bexarotene to reduce polyposis in patients with FAP using in silico tools, ex vivo, and in vivo models. This investigation provides the essential groundwork for moving this drug combination forward into a clinical trial.

Supplementary Tables S1-S4

S1. Variants of unknown significance detected in the MD Anderson cohort. S2. Clinical characteristics of the VUS carriers reported in Supplementary Table 1. Pathogenic mutations detected in the same patient carrying a VUS are presented in bold. S3. Clinical characteristics of carriers of variants reclassified as InSIGHT Class 1 and 5. These variants have been used for validation purposes. S4. Validation set of splicing variants obtained from the InSiGHT database that have been already reclassified as Class 1 and 5. S5. Classification at the RNA level using three bioinformatic in silico programs of all reported VUS. Results in gray indicate major alterations which are those that are predicted to destroy or create splicing sites or produce a SS score modification {greater than or equal to}20%; Predictions are interpreted as inconclusive when the same results are not obtained by all the programs used. S6. Detailed results of in silico RNA bioinformatic prediction tools for those variants classified as affecting Splicing Sites or Inconclusive by In silico prediction tools. Results in gray indicate major alterations. For splice site predictions, major alterations are those that are predicted to destroy or create splicing sites or produce a SS score modification {greater than or equal to}20%; Predictions are interpreted as inconclusive when the same results are not obtained by all the programs used. S7. Splicing validation set using three bioinformatic in silico programs of a set of splicing variants obtained from the InSIGHT database and that have been already re-classified as Class 1 and 5. Results in gray indicate major alterations, which are destroyed or created SS or score modifications {greater than or equal to}20%; Predictions are interpreted as inconclusive when only one program predict pathogenicity. S8. Detailed in silico RNA bioinformatic prediction results for splicing variants already reclassified as class 5 used for validation of in silico tools. Variants presented here were predicted to be Aberrant or Inconclusive based on our RNA in silico approach. Results in gray indicate major alterations. For splice site prediction, major alternations are destroyed or created SS or score modifications {greater than or equal to}20%; Predictions are interpreted as inconclusive when the same results are not obtained by all the programs used. S9. Classification at protein level of reported VUS using five bioinformatic in silico programs. Results in gray indicate major alterations. Predictions are interpreted as inconclusive when the same results are not obtained by all the programs used. S10. Detailed results of in silico analysis at protein level. S11. Summary of the clinical characteristics and mRNA and protein in silico predictions of the identified MMR VUS. Raw data concerning these analyses is detailed in Supplementary Tables 1-6. S12. Classification at the RNA level using three bioinformatic in silico programs of Identified Variants reclasified as InSIGHT Class 1 and 5 from the MD Anderson database. These variants have been used for validation purposes. Results in gray indicate major alterations, which are destroyed or created SS or score modifications {greater than or equal to}20%; Predictions are interpreted as inconclusive when only one program predict pathogenicity. S13. Detailed in silico RNA bioinformatic prediction results for variants reclassified as InSIGHT class 1 and 5 that obtained results of affecting splicing sites or Inconclusive. Results in gray indicate major alterations. For splice site prediction, major alternations are destroyed or created SS or score modifications {greater than or equal to}20%; Predictions are interpreted as inconclusive when the same results are not obtained by all the programs used. S14. Classification at protein level using five bioinformatic in silico programs of variants reclassified as InSIGHT Class 1 and 5. These variants were used for validation purposes. Results in gray indicate major alterations. Predictions are interpreted as inconclusive when the same results are not obtained by all the programs used. S15. Summary of the clinical characteristics and mRNA and protein in silico analyses of variants reclassified as InSIGHT Class 1 and 5. These variants were used for valiadation purposes. Information concerning these variants is detailed in supplementary Tables 8-11.

New treatments are needed to address persistent unmet clinical needs for diffuse large B-cell lymphoma (DLBCL). Overexpression of transferrin receptor 1 (TFR1) is common across cancer and permits cell-surface targeting of specific therapies in preclinical and clinical studies of various solid tumors. Here, we developed novel nanocarrier delivery of chemotherapy via TFR1-mediated endocytosis, assessing this target for the first time in DLBCL. Analysis of published datasets showed novel association of increased TFR1 expression with high-risk DLBCL cases. Carbon–nitride dots (CND) are emerging nanoparticles with excellent in vivo stability and distribution and are adaptable to covalent conjugation with multiple substrates. In vitro, linking doxorubicin (Dox) and transferrin (TF) to CND (CND–Dox–TF, CDT) was 10–100 times more potent than Dox against DLBCL cell lines. Gain- and loss-of-function studies and fluorescent confocal microscopy confirmed dependence of these effects on TFR1-mediated endocytosis. In contrast with previous therapeutics directly linking Dox and TF, cytotoxicity of CDT resulted from nuclear entry by Dox, promoting double-stranded DNA breaks and apoptosis. CDT proved safe to administer in vivo, and when incorporated into standard frontline chemoimmunotherapy in place of Dox, it improved overall survival by controlling patient-derived xenograft tumors with greatly reduced host toxicities. Nanocarrier-mediated Dox delivery to cell-surface TFR1, therefore, warrants optimization as a potential new therapeutic option in DLBCL.Significance:Targeted nanoparticle delivery of doxorubicin chemotherapy via the TRF1 receptor presents a new opportunity against high-risk DLBCL tumors using potency and precision.

Figures S1, S2, S3 and S4. APC and KRAS genotyping of crypts and bulk biopsies in adenomas from MAP, UPF, LS and cMMRD cases. Figures S5, S6 and S7. APC and KRAS genotyping of crypts and bulk biopsies in adenomas from SPO cases. Figure S8, S9 and S10. Hyerarchical clustering analysis of crypts based on KRAS genotyping results. Figure S11. Comparative analysis of mutant allele discrimination by (A) Light Cycler 480 (Roche) and (B) nanofluidic PCR using Dynamic array (Fluidigm). Figure S12. A. Comparative analysis of KRAS genotyping using whole genome amplified (WGA) DNA or pre-amplified DNA using 15 cycles of a nested PCR. Figure S13. Genotyping results including water controls of random KRAS hotspot mutation analysis after performing a pre-amplification step using a nested PCR apporach. Figure S14. Independent validation of KRAS hotspot mutation that have been detected by Nanofluidic Dynamic array using the Nanofluidic Digital PCR genotyping as an alternative approach. Figure S15. Independent validation of KRAS hotspot mutation that have been detected by Nanofluidic Dynamic array using the Nanofluidic Digital PCR genotyping as an alternative approach.

Supplementary Figures S1-S6

Purpose: Determination of microsatellite instability (MSI) by PCR is the gold standard; however, IHC of mismatch repair (MMR) proteins is frequently performed instead. The reliability of these methods on postneoadjuvant therapy specimens is unknown. We examined the effect of neoadjuvant therapy on MSI results by PCR and IHC.Experimental design: A total of 239 colorectal cancers resected after neoadjuvant therapy were assessed for MSI with PCR and IHC. PCR and IHC results for matched paired pre- and posttreatment specimens were compared. In parallel, 2 isogenic cell lines conditioned for MMR functioning and 2 different patient-derived xenografts (PDXs) were exposed to chemotherapy, radiation, or both. We also examined whether establishment of PDXs induced MSI changes in 5 tumors. IHC and MSI were tested after treatment to assess for changes.Results: We identified paired pre- and posttreatment specimens for 37 patients: 2 with PCR only, 34 with IHC only, and 1 with both. All 3 patients with PCR had microsatellite stable pre- and posttreatment specimens. Of the 35 patients with IHC, 30 had intact MMR proteins in pre- and posttreatment specimens, 1 had equivocal MLH1 staining in the pretreatment and loss in the posttreatment specimen, and 4 had intact pretreatment MSH6 but variable posttreatment staining. In the experimental setting, no changes in MSI status were detected after treatment or tumor implantation in animals.Conclusions: Our findings show that the expression of MMR proteins, commonly MSH6, can change after neoadjuvant therapy and confirm PCR as the gold-standard test for MSI after neoadjuvant therapy. Clin Cancer Res; 23(17); 5246–54. ©2017 AACR.

The analysis of MUTYH-associated polyposis cases of the EPIPOLIP cohort confirms the importance of including serrated polyps in the diagnostic work-up of patients with oligopolyposis, suggests a role for screening polyps for the somatic c.34G>T KRAS mutation, and allows the implementation of a genetic testing strategy based on population data. Clin Cancer Res; 20(5); 1061–3. ©2014 AACR.

Supplementary Figure Legend

Purpose: The majority of genomic alterations causing intratumoral heterogeneity (ITH) in colorectal cancer are thought to arise during early stages of carcinogenesis as a burst but only after truncal mutations in APC have expanded a single founder clone. We have investigated if the initial source of ITH is consequent to multiple independent lineages derived from different crypts harboring distinct truncal APC and driver KRAS mutations, thus challenging the prevailing monoclonal monocryptal model.Experimental Design: High-depth next-generation sequencing and SNP arrays were performed in whole-lesion extracts of 37 familial adenomatous polyposis colorectal adenomas. Also, ultrasensitive genotyping of hotspot mutations of APC and KRAS was performed using nanofluidic PCRs in matched bulk biopsies (n = 59) and crypts (n = 591) from 18 adenomas and seven carcinomas and adjacent normal tissues.Results: Multiple co-occurring truncal APC and driver KRAS alterations were uncovered in whole-lesion extracts from adenomas and subsequently confirmed to belong to multiple clones. Ultrasensitive genotyping of bulk biopsies and crypts revealed novel undetected APC mutations that were prominent among carcinomas, whereas abundant wild-type APC crypts were detected in adenomas. KRAS mutational heterogeneity within crypts was evident in both adenomas and carcinomas with a higher degree of concordance between biopsy and crypt genotyping in carcinomas. Nonrandom heterogeneity among crypts was also observed.Conclusions: The striking degree of nonrandom intercrypt heterogeneity in truncal and driver gene mutations observed in adenomas and carcinomas is consistent with a polycryptal model derived from multiple independent initiation linages as the source of early ITH in colorectal carcinogenesis. Clin Cancer Res; 23(19); 5936–47. ©2017 AACR.

Supplementary Material and Methods

Table S1. Summary of adenomas with multiple APC and KRAS somatic hits identified by next-generation sequencing. Table S2. Clinical and pathologic characteristics of patients analyzed in this manuscript. Table S3. Analysis of APC, KRAS and 5q loss using AmpliSeq and SNP array TableS4. Number of normal mucosa, adenomas, tumors and crypts analyzed per case. NM; normal mucosa. Table S5. Analytical sensibility of Light Cycler® 480 (Roche) and dynamic array (Fluidigm) to detect KRAS mutations. Table S6. In silico of the APC somatic hits observed by next-generaiton sequencing that were labelled as VUS. B, benign; N, neutral; D, damaging; P, Probably damaging. Table S7. APC analysis of adenomas and carcinomas in bulk biopsies and isolated crypts. The analysis of adjancent normal mucosa was not performed. Table S8. KRAS genotyping results of adenomas and carcinomas by digital and dynamic array (Fluidigm) in bulk biopsies and isolated crypts Table S9. Primers and probes used in this manuscript.

Supplemental Figures 1-9. Figure S1. Carbon-Nitride Dot Synthesis. Figure S2. Characterization of CND-Dox-TF. Figure S3. CND cytotoxicity. Figure S4. Cell surface TFR1 expression and receptor recycling. Figure S5. Rapid nuclear entry by Dox after CND-Dox-TF treatment in DLBCL. Figure S6. HEK293 is a model cell line for elucidating CND-Dox-TF mechanism. Figure S7. CND-Dox-TF working dose identified. Figure S8. CND-Dox-TF has improved toxicity profile compared to Dox. Figure S9. R-nanoCHOP treatment has favorable toxicity profile in non-malignant organs.

Supplementary Materials and Methods (Includes reference to Table S9 and Figures S11-15)

Supplementary Tables S1-S9

Supplementary Table 1. Patient Demographic Characteristics. *2 patients with metachronous tumors, 1 poor and 1 moderate; **One patient with both pre- and posttreatment IHC and MSI testing. Supplementary Table 2. Tumor characteristics and results of the IHC and MSI analysis of those cases exhibiting loss of MSH6 after neoadjuvant treatment. Abbreviations: yp, pathologic stage after neoadjuvant treatment; NT, not tested; pre-tx, pre-treatment; post-tx, post-treatment; MSS, microsatellite stable; MSI-L, microsatellite low. Supplementary Table 3. MSI and IHC Analysis of in vivo pre- and post-treatment data. Abbreviations: yp, pathologic stage after neoadjuvant treatment; pre-tx, pre-treatment; post-tx, post-treatment; MSS, microsatellite stable; MSI-L, microsatellite low. Supplementary Table 4. PDX Patient Demographic Characteristics (n = 5) Supplementary Figure 1. Confirmation of MLH1 loss in the cell line HCT116 was performed via Sanger sequencing (A) and Western Blot (B) Supplementary Figure 2. In vitro treatment method. MMR deficient (HCT116) and proficient (HCT116+Ch3) isogenic cell lines were exposed to treatment every 48 hours for 3 cycles. On Day 1, 500,000 cells/10 mm plate were seeded and allowed to grow exponentially for 24-48 hours. Cells were then treated with radiation or drug. After 48hrs, the cells were allowed to grow in drug-free medium until confluency. Cells were split and allowed to grow again in drug-free medium for 48 hours before being treated with the next round of treatment. This process was repeated for 3 cycles. After 48 hours of the 3rd treatment, the slides were fixed with 4% paraformaldehyde.

Related Article from Establishing a Diagnostic Road Map for MUTYH-Associated Polyposis

Lynch syndrome is the most common cause of hereditary colorectal cancer and is secondary to germline alterations in one of four DNA mismatch repair (MMR) genes. Here we aimed to provide novel insights into the initiation of MMR-deficient (MMRd) colorectal carcinogenesis by characterizing the expression profile of MMRd intestinal stem cells (ISC). A tissue-specific MMRd mouse model (Villin-Cre;Msh2LoxP/LoxP) was crossed with a reporter mouse (Lgr5-EGFP-IRES-creERT2) to trace and isolate ISCs (Lgr5+) using flow cytometry. Three different ISC genotypes (Msh2-KO, Msh2-HET, and Msh2-WT) were isolated and processed for mRNA-seq and mass spectrometry, followed by bioinformatic analyses to identify expression signatures of complete MMRd and haplo-insufficiency. These findings were validated using qRT-PCR, IHC, and whole transcriptomic sequencing in mouse tissues, organoids, and a cohort of human samples, including normal colorectal mucosa, premalignant lesions, and early-stage colorectal cancers from patients with Lynch syndrome and patients with familial adenomatous polyposis (FAP) as controls. Msh2-KO ISCs clustered together with differentiated intestinal epithelial cells from all genotypes. Gene-set enrichment analysis indicated inhibition of replication, cell-cycle progression, and the Wnt pathway and activation of epithelial signaling and immune reaction. An expression signature derived from MMRd ISCs successfully distinguished MMRd neoplastic lesions of patients with Lynch syndrome from FAP controls. SPP1 was specifically upregulated in MMRd ISCs and colocalized with LGR5 in Lynch syndrome colorectal premalignant lesions and tumors. These results show that expression signatures of MMRd ISC recapitulate the initial steps of Lynch syndrome carcinogenesis and have the potential to unveil novel biomarkers of early cancer initiation.Significance:The transcriptomic and proteomic profile of MMR-deficient intestinal stem cells displays a unique set of genes with potential roles as biomarkers of cancer initiation and early progression.

Please see the Editorial Comment by Candice Bolan discussing this article. The treatment of rectal cancer centers around the distinct but related goals of management of distant metastases and manag...

Rectal neuroendocrine carcinomas (rNECs) are poorly characterized and, given their aggressive nature, optimal management is not well-established. We therefore sought to describe clinicopathologic traits, treatment details, and survival patterns for patients with rNECs. Patients captured in the National Cancer Database (NCDB; 2004–2016) with rNECs managed with observation, chemotherapy, or proctectomy ± chemotherapy were considered for analysis. The inclusion criteria were met by 777 patients. Mean age was 62.4 years, 45% were male, 80% were Caucasian, 40% presented with lymph nodes metastases, and 49% presented with distant metastases. Chemotherapy and surgical resection were administered in 72 and 19% of cases, respectively. Median overall survival (OS) was 0.83 years (1 year, 41%; 3 years, 13%; 5 years, 10%). During the study interval, 659 (85%) patients died, with a median follow-up of 0.79 years. On multivariable analysis, age ≥60 years, male sex, and distant metastases were associated with worse survival; surgical resection and administration of chemotherapy were associated with a reduced risk of death. Among non-metastatic patients treated with surgical resection, administration of chemotherapy was protective, while a positive lymph node ratio (LNR) ≥42% (median value) was associated with an increased risk of death. There was no difference in the number of examined lymph nodes between LNR cohorts. Patients with rNECs experience dismal survival outcomes, including those with non-metastatic disease treated with curative-intent surgical resection. Neoadjuvant therapy can serve as a useful biologic test, and surgical resection should be judiciously employed.

Lynch syndrome is the most common cause of hereditary colorectal cancer and is secondary to germline alterations in one of four DNA mismatch repair (MMR) genes. Here we aimed to provide novel insights into the initiation of MMR-deficient (MMRd) colorectal carcinogenesis by characterizing the expression profile of MMRd intestinal stem cells (ISC). A tissue-specific MMRd mouse model (Villin-Cre;Msh2LoxP/LoxP) was crossed with a reporter mouse (Lgr5-EGFP-IRES-creERT2) to trace and isolate ISCs (Lgr5+) using flow cytometry. Three different ISC genotypes (Msh2-KO, Msh2-HET, and Msh2-WT) were isolated and processed for mRNA-seq and mass spectrometry, followed by bioinformatic analyses to identify expression signatures of complete MMRd and haplo-insufficiency. These findings were validated using qRT-PCR, IHC, and whole transcriptomic sequencing in mouse tissues, organoids, and a cohort of human samples, including normal colorectal mucosa, premalignant lesions, and early-stage colorectal cancers from patients with Lynch syndrome and patients with familial adenomatous polyposis (FAP) as controls. Msh2-KO ISCs clustered together with differentiated intestinal epithelial cells from all genotypes. Gene-set enrichment analysis indicated inhibition of replication, cell-cycle progression, and the Wnt pathway and activation of epithelial signaling and immune reaction. An expression signature derived from MMRd ISCs successfully distinguished MMRd neoplastic lesions of patients with Lynch syndrome from FAP controls. SPP1 was specifically upregulated in MMRd ISCs and colocalized with LGR5 in Lynch syndrome colorectal premalignant lesions and tumors. These results show that expression signatures of MMRd ISC recapitulate the initial steps of Lynch syndrome carcinogenesis and have the potential to unveil novel biomarkers of early cancer initiation. Significance: The transcriptomic and proteomic profile of MMR-deficient intestinal stem cells displays a unique set of genes with potential roles as biomarkers of cancer initiation and early progression.

New treatments are needed to address persistent unmet clinical needs for diffuse large B-cell lymphoma (DLBCL). Overexpression of transferrin receptor 1 (TFR1) is common across cancer and permits cell-surface targeting of specific therapies in preclinical and clinical studies of various solid tumors. Here, we developed novel nanocarrier delivery of chemotherapy via TFR1-mediated endocytosis, assessing this target for the first time in DLBCL. Analysis of published datasets showed novel association of increased TFR1 expression with high-risk DLBCL cases. Carbon–nitride dots (CND) are emerging nanoparticles with excellent in vivo stability and distribution and are adaptable to covalent conjugation with multiple substrates. In vitro, linking doxorubicin (Dox) and transferrin (TF) to CND (CND–Dox–TF, CDT) was 10–100 times more potent than Dox against DLBCL cell lines. Gain- and loss-of-function studies and fluorescent confocal microscopy confirmed dependence of these effects on TFR1-mediated endocytosis. In contrast with previous therapeutics directly linking Dox and TF, cytotoxicity of CDT resulted from nuclear entry by Dox, promoting double-stranded DNA breaks and apoptosis. CDT proved safe to administer in vivo, and when incorporated into standard frontline chemoimmunotherapy in place of Dox, it improved overall survival by controlling patient-derived xenograft tumors with greatly reduced host toxicities. Nanocarrier-mediated Dox delivery to cell-surface TFR1, therefore, warrants optimization as a potential new therapeutic option in DLBCL. Significance: Targeted nanoparticle delivery of doxorubicin chemotherapy via the TRF1 receptor presents a new opportunity against high-risk DLBCL tumors using potency and precision.

Context.— During the past 3 decades, numerous articles in the literature have offered terminology, diagnostic criteria, and consensus recommendations regarding the entity currently referred to by the World Health Organization as sessile serrated lesion. Given the many names and various, variably reproducible diagnostic criteria ascribed to sessile serrated lesion, confusion persists for many pathologists and gastroenterologists regarding the diagnosis. This distinction is important, as sessile serrated lesion can progress to malignancy, unlike its main differential diagnosis, hyperplastic polyp. Research studies have shed light on the characteristic architecture and morphology, immunohistochemical patterns, and molecular alterations of sessile serrated lesion, and multiple consensus meetings around the globe have developed their criteria and nomenclature, often clashing or mixing terms. Objective.— To provide a narrative review from the entity's early description to our current understanding. Data Sources.— The existing scientific and clinical literature, published texts, medical society recommendations, and specialty consensus guidelines. Conclusions.— The current World Health Organization criteria are a distillation of this scientific process, but terminology is still a point of contention worldwide.

Background Appendiceal adenocarcinoma (AA) is an orphan disease with unique clinical attributes but often treated as colorectal cancer (CRC). Understanding key molecular differences between AA and CRC is critical. Methods We performed retrospective analyses of AA patients (N = 266) with tumour and/or blood next-generation sequencing (NGS) (2013–2018) with in-depth clinicopathological annotation. Overall survival (OS) was examined. For comparison, CRC cohorts annotated for sidedness, consensus molecular subtypes (CMS) and mutations (N = 3283) were used. Results Blood-NGS identified less RAS/GNAS mutations compared to tissue-NGS (4.2% vs. 60.9%, P RAS (56.2%), GNAS (28.1%) and TP53 (26.9%) were most frequent mutations. Well/moderately differentiated tumours harboured more RAS (69.2%/64.0% vs. 40.5%) and GNAS (48.7%/32.0% vs. 10.1%) while moderate/poorly differentiated tumours had more TP53 (26.0%/27.8% vs. 7.7%) mutations. Appendiceal adenocarcinoma (compared to CRC) harboured significantly fewer APC (9.1% vs. 55.4%) and TP53 (26.9% vs. 67.5%) and more GNAS mutations (28.1% vs. 2.0%) (P Conclusion Integrated clinico-molecular profiling of AA identified key molecular drivers distinct from CRC. Appendiceal adenocarcinoma has a predominantly grade-driven biology that trumps mutations.

The role and sequencing of short-course radiation therapy (SCRT) in the preoperative management of locally advanced rectal cancer is unclear. This study of 39 patients compares outcomes between those who had surgery within 14 days after finishing SCRT and those who were delayed. Our data show similar outcomes between these groups, suggesting SCRT is well-tolerated regardless of sequence. BACKGROUND: The role of neoadjuvant short-course radiation therapy (SCRT) in treating rectal adenocarcinoma is a topic of ongoing debate. Growing interest in total neoadjuvant therapy has spurred discussion on the optimal sequence of preoperative SCRT and chemotherapy. PATIENTS AND METHODS: All patients receiving SCRT (5 Gy × 5 fractions) were identified. Details about preoperative treatments, radiation toxicities, and postoperative complications were collected. Patients were divided into 2 groups: those who underwent surgery within 14 days of completing SCRT and those with a longer delay. Outcomes compared included extent of pathologic response, margin-negative resection rate, acute radiation toxicities, and postoperative complications. RESULTS: Fifty-seven patients with locally advanced or metastatic rectal cancer received SCRT between 2008 and 2018. Thirty-nine of 57 patients underwent definitive pelvic surgery with total mesorectal excision. There were no significant differences in tumor downstaging, radial margin status, or percent tumor viability between patients with immediate surgery versus delayed surgery. The delay group had higher rates of nodal downstaging (64.7% vs. 18.2%; P = .003). There were no differences in total or grade 3+ gastrointestinal radiation toxicity, postoperative complications, reoperation, readmission, and mortality between the 2 groups. CONCLUSIONS: Though not yet common in the United States, SCRT has compared favorably with long course chemoradiation in multiple trials. Moreover, it is associated with greater efficiency and less disruption to chemotherapy. Our data show similar response and toxicity outcomes between the immediate and delay groups, suggesting SCRT is well-tolerated regardless of treatment sequence. Recently completed prospective trials may reveal the optimal preoperative treatment sequence.

Primary epithelioid hemangioendotheliomas of the liver (EHL) are rare tumors with a low incidence. The molecular background of EHL is still under investigation, with WWTR1-CAMPTA1 mutation may function as a tumor marker. Commonly, this tumor is misdiagnosed with angiosarcoma, cholangiocarcinomas, metastatic carcinoma, and hepatocellular carcinoma (sclerosing variant). Characteristic features on imaging modalities such as ultrasound, computed tomography, magnetic resonance imaging and positron emission tomography/computed tomography guide in diagnosis and staging. The “halo sign” and the “lollipop sign” on computed tomography and magnetic resonance imaging are described in the literature. Currently, there are no standardized guidelines for treating EHL with treatment options are broad including: chemotherapy, ablation, surgery and liver transplantation with inconsistent results.

Patients with T4 colon adenocarcinomas have an increased risk of peritoneal metastases (PM) but the histopathologic risk factors for its development are not well-described.The purpose of this study was to determine factors associated with PM, time to recurrence, and survival after recurrence among patients with T4 colon cancer.Patients with pathologic T4 colon cancer who underwent curative resection from 2005 to 2017 were identified from a prospectively maintained institutional database and classified by recurrence pattern: (a) none - 68.8%; (b) peritoneal only - 7.9%; (c) peritoneal and extraperitoneal - 9.9%; and (d) extraperitoneal only - 13.2%. Associations between PM development and patient, primary tumor, and treatment factors were assessed.Overall, 151 patients were analyzed, with a median follow-up of 66.2 months; 27 patients (18%) developed PM (Groups B and C) and 20 (13%) patients recurred at non-peritoneal sites only (Group D). Median time to developing metastases was shorter for Groups B and C compared with Group D (B and C: 13.7 months; D: 46.7 months; p = 0.022). Tumor deposits (TDs) and nodal stage were associated with PM (p 0.05), and TDs (p = 0.048) and LVI (p = 0.015) were associated with additional extraperitoneal recurrence. Eleven (41%) patients with PM underwent salvage surgery, and median survival after recurrence was associated with the ability to undergo cytoreduction (risk ratio 0.20, confidence interval 0.06-0.70).PM risk after resection of T4 colon cancer is independently associated with factors related to lymphatic spread, such as N stage and TDs. Well-selected patients can undergo cytoreduction with long-term survival. These findings support frequent postoperative surveillance and aggressive early intervention, including cytoreduction.

Aim Complete mesocolic excision (CME) with central vascular ligation (CVL) has been advocated for right colon adenocarcinoma (RC), but the radicality of vascular dissection remains controversial. Our aim is to report outcomes of selective CVL (D3 lymphadenectomy) during minimally invasive CME for RC. Method A prospective database identified patients who were treated for RC between 2009 and 2016. Minimally invasive CME was standard. The radicality of lymphadenectomy was defined as high ligation (HL) versus CVL based on operative reports and videos. Two blinded radiologists independently evaluated the pre- and postoperative CT scans for radiographically abnormal nodes. Results Of 197 patients who underwent CME, HL was performed in 56 (28%) and CVL in 141 (72%). There were no baseline differences in age, sex, body mass index, American Society of Anesthesiologists score or pathological staging, and there were no major intra-operative complications in either group (including no major vascular injuries). The median total number of nodes retrieved was 27 and 31 (P = 0.011) in HL and CVL groups, resepctively, with pathologically positive nodes identified in 33.9% and 39.8% (P = 0.704), respectively. Preoperative imaging identified abnormal cN3 nodes in 1.5% of patients; all of whom underwent CVL. No abnormal cN2 or cN3 nodes remained on postoperative imaging. The 60-day mortality was 0.5%, and major morbidity was 4%. One patient (0.5%) had an anastomotic recurrence after a median follow-up of 22 months. Conclusion With imperfect preoperative clinical nodal staging, and in the absence of randomized data, the low morbidity and oncological outcomes observed support the approach of CME with HL as a minimum standard, with CVL (D3 lymphadenectomy) in selected cases.

Germline mutations in the tumor suppressor Adenomatous Polyposis Coli (APC) define Familial Adenomatous Polyposis (FAP), the genetic predisposition to developing adenomatous polyps. Recent sequencing of FAP adenomas have challenged established dogma that APC mutations alone represent the adenoma mutational landscape because recurrent somatic mutations in non-WNT pathway genes were also discovered. In particular, one of these novel genes, CNOT3, presented E20K and E70K mutations that are predicted to be deleterious in silico. We utilized zebrafish embryos to determine if these mutations affect CNOT3 function and perform novel biology in an APC-dependent pathway in vivo. Human CNOT3 (hCNOT3) and E20K mRNA injection rescued zebrafish cnot3a knockdown lordosis phenotype while E70K did not. In the FAP apcmcr zebrafish model, we show that ctbp1, but not retinoic acid, regulates cnot3a expression. Injection of hCNOT3 and E20K, but not E70K, to homozygous apcmcr zebrafish initiated gut differentiation while cnot3a knockdown in wildtype embryos led to decreased intestinal development and differentiation. Finally, targeted sequencing of 37 additional FAP adenomas revealed CNOT3 mutations in 20% of these samples. Overall, our work supports a mechanism where CTBP1 regulates CNOT3 and that overall CNOT3 perturbation could work in concert with germline APC mutations in advancing adenomas to a more transformed state prior to progression to adenocarcinoma.

Familial adenomatous polyposis (FAP) is a hereditary colorectal cancer syndrome, which results in the development of hundreds of adenomatous polyps carpeting the gastrointestinal tract. NSAIDs have reduced polyp burden in patients with FAP and synthetic rexinoids have demonstrated the ability to modulate cytokine-mediated inflammation and WNT signaling. This study examined the use of the combination of an NSAID (sulindac) and a rexinoid (bexarotene) as a durable approach for reducing FAP colonic polyposis to prevent colorectal cancer development. Whole transcriptomic analysis of colorectal polyps and matched normal mucosa in a cohort of patients with FAP to identify potential targets for prevention in FAP was performed. Drug-dose synergism of sulindac and bexarotene in cell lines and patient-derived organoids was assessed, and the drug combination was tested in two different mouse models. This work explored mRNA as a potential predictive serum biomarker for this combination in FAP. Overall, transcriptomic analysis revealed significant activation of inflammatory and cell proliferation pathways. A synergistic effect of sulindac (300 μmol/L) and bexarotene (40 μmol/L) was observed in FAP colonic organoids with primary targeting of polyp tissue compared with normal mucosa. This combination translated into a significant reduction in polyp development in ApcMin/+ and ApcLoxP/+-Cdx2 mice. Finally, the reported data suggest miRNA-21 could serve as a predictive serum biomarker for polyposis burden in patients with FAP. These findings support the clinical development of the combination of sulindac and bexarotene as a treatment modality for patients with FAP. Prevention Relevance: This study identified a novel chemopreventive regimen combining sulindac and bexarotene to reduce polyposis in patients with FAP using in silico tools, ex vivo, and in vivo models. This investigation provides the essential groundwork for moving this drug combination forward into a clinical trial.

Rectal neuroendocrine carcinomas (rNECs) are poorly characterized and, given their aggressive nature, optimal management is not well-established. We therefore sought to describe clinicopathologic traits, treatment details, and survival patterns for patients with rNECs.Patients captured in the National Cancer Database (NCDB; 2004-2016) with rNECs managed with observation, chemotherapy, or proctectomy ± chemotherapy were considered for analysis.The inclusion criteria were met by 777 patients. Mean age was 62.4 years, 45% were male, 80% were Caucasian, 40% presented with lymph nodes metastases, and 49% presented with distant metastases. Chemotherapy and surgical resection were administered in 72 and 19% of cases, respectively. Median overall survival (OS) was 0.83 years (1 year, 41%; 3 years, 13%; 5 years, 10%). During the study interval, 659 (85%) patients died, with a median follow-up of 0.79 years. On multivariable analysis, age ≥60 years, male sex, and distant metastases were associated with worse survival; surgical resection and administration of chemotherapy were associated with a reduced risk of death. Among non-metastatic patients treated with surgical resection, administration of chemotherapy was protective, while a positive lymph node ratio (LNR) ≥42% (median value) was associated with an increased risk of death. There was no difference in the number of examined lymph nodes between LNR cohorts.Patients with rNECs experience dismal survival outcomes, including those with non-metastatic disease treated with curative-intent surgical resection. Neoadjuvant therapy can serve as a useful biologic test, and surgical resection should be judiciously employed.

Hepatic steatosis can lead to liver cancer, cirrhosis, and portal hypertension. There are two main types, non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease. The detection and quantification of hepatic steatosis with lifestyle changes can slow the evolution from NAFLD to steatohepatitis. Currently, the gold standard for the quantification of fat in the liver is biopsy, has some limitations. Hepatic steatosis is frequently detected during cross sectional imaging. Ultrasound (US), Computed Tomography (CT), and Magnetic Resonance Imaging (MRI) provide noninvasive assessment of liver parenchyma and can detect fat infiltration in the liver. However, the non-invasive quantification of hepatic steatosis by imaging has been challenging. Recent MRI techniques show great promise in the detection and quantification of liver fat. The aim of this article is to review the utilization of non-invasive imaging modalities for the detection and quantification of hepatic steatosis, to evaluate their advantages and limitations.

Objective Patients with Lynch syndrome (LS) are at markedly increased risk for colorectal cancer. It is being increasingly recognised that the immune system plays an essential role in LS tumour development, thus making an ideal target for cancer prevention. Our objective was to evaluate the safety, assess the activity and discover novel molecular pathways involved in the activity of naproxen as primary and secondary chemoprevention in patients with LS. Design We conducted a Phase Ib, placebo-controlled, randomised clinical trial of two dose levels of naproxen sodium (440 and 220 mg) administered daily for 6 months to 80 participants with LS, and a co-clinical trial using a genetically engineered mouse model of LS and patient-derived organoids (PDOs). Results Overall, the total number of adverse events was not different across treatment arms with excellent tolerance of the intervention. The level of prostaglandin E2 in the colorectal mucosa was significantly decreased after treatment with naproxen when compared with placebo. Naproxen activated different resident immune cell types without any increase in lymphoid cellularity, and changed the expression patterns of the intestinal crypt towards epithelial differentiation and stem cell regulation. Naproxen demonstrated robust chemopreventive activity in a mouse co-clinical trial and gene expression profiles induced by naproxen in humans showed perfect discrimination of mice specimens with LS and PDOs treated with naproxen and control. Conclusions Naproxen is a promising strategy for immune interception in LS. We have discovered naproxen-induced gene expression profiles for their potential use as predictive biomarkers of drug activity. Trial registration number gov Identifier: NCT02052908

Aim There are limited outcome data for lateral pelvic lymph node dissection (LPLND) following neoadjuvant chemoradiotherapy (nCRT), particularly in the West. Our aim was to evaluate the short-term perioperative and oncological outcomes of robotic LPLND at a single cancer centre. Method A retrospective analysis of a prospective database of consecutive patients undergoing robotic LPLND for rectal cancer between November 2012 and February 2020 was performed. The main outcomes were short-term perioperative and oncological outcomes. Major morbidity was defined as Clavien-Dindo grade 3 or above. Results Forty patients underwent robotic LPLND during the study period. The mean age was 54 years (SD ± 15 years) and 13 (31.0%) were female. The median body mass index was 28.6 kg/m2 (IQR 25.5-32.6 kg/m2 ). Neoadjuvant CRT was performed in all patients. Resection of the primary rectal cancer and concurrent LPLND occurred in 36 (90.0%) patients, whilst the remaining 4 (10.0%) patients had subsequent LPLND after prior rectal resection. The median operating time was 420 min (IQR 313-540 min), estimated blood loss was 150 ml (IQR 55-200 ml) and length of hospital stay was 4 days (IQR 3-6 days). The major morbidity rate was 10.0% (n = 4). The median lymph node harvest from the LPLND was 6 (IQR 3-9) and 13 (32.5%) patients had one or more positive LPLNs. The median follow-up was 16 months (IQR 5-33 months), with 1 (2.5%) local central recurrence and 7 (17.5%) patients developing distant disease, resulting in 3 (7.5%) deaths. Conclusion Robotic LPLND for rectal cancer can be performed in Western patients to completely resect extra-mesorectal LPLNs and is associated with acceptable perioperative morbidity.

Background Gene expression-based profiling of colorectal cancer (CRC) can be used to identify four molecularly homogeneous consensus molecular subtype (CMS) groups with unique biologic features. However, its applicability to colorectal premalignant lesions remains unknown. Patients and methods We assembled the largest transcriptomic premalignancy dataset by integrating different public and proprietary cohorts of adenomatous and serrated polyps from sporadic (N = 311) and hereditary (N = 78) patient populations and carried out a comprehensive analysis of carcinogenesis pathways using the CMS random forest (RF) classifier. Results Overall, transcriptomic subtyping of sporadic and hereditary polyps revealed CMS2 and CMS1 subgroups as the predominant molecular subtypes in premalignancy. Pathway enrichment analysis showed that adenomatous polyps from sporadic or hereditary cases (including Lynch syndrome) displayed a CMS2-like phenotype with WNT and MYC activation, whereas hyperplastic and serrated polyps with CMS1-like phenotype harbored prominent immune activation. Rare adenomas with CMS4-like phenotype showed significant enrichment for stromal signatures along with transforming growth factor-β activation. There was a strong association of CMS1-like polyps with serrated pathology, right-sided anatomic location and BRAF mutations. Conclusions Based on our observations made in premalignancy, we propose a model of pathway activation associated with CMS classification in colorectal carcinogenesis. Specifically, while adenomatous polyps are largely CMS2, most hyperplastic and serrated polyps are CMS1 and may transition into other CMS groups during evolution into carcinomas. Our findings shed light on the transcriptional landscape of premalignant colonic polyps and may help guide the development of future biomarkers or preventive treatments for CRC.