CCR5 and CCL5 gene expression in colorectal cancer: comprehensive profiling and clinical value.

BACKGROUND: The C-C motif chemokine receptor 5 (CCR5)/C-C motif chemokine ligand 5 (CCL5) axis plays a major role in colorectal cancer (CRC). We aimed to characterize the molecular features associated with CCR5/CCL5 expression in CRC and to determine whether CCR5/CCL5 levels could impact treatment outcomes. METHODS: 7604 CRCs tested with NextGen Sequencing on DNA and RNA were analyzed. Molecular features were evaluated according to CCR5 and CCL5 tumor gene expression quartiles. The impact on treatment outcomes was assessed in two cohorts, including 6341 real-world patients and 429 patients from the Cancer and Leukemia Group B (CALGB)/SWOG 80405 trial. RESULTS: CCR5/CCL5 expression was higher in right-sided versus left-sided tumors, and positively associated with consensus molecular subtypes 1 and 4. Higher CCR5/CCL5 expression was associated with higher tumor mutational burden, deficiency in mismatch repair and programmed cell death ligand 1 (PD-L1) levels. Additionally, high CCR5/CCL5 were associated with higher immune cell infiltration in the tumor microenvironment (TME) of MMR proficient tumors. Ingenuity pathway analysis revealed upregulation of the programmed cell death protein 1 (PD-1)/PD-L1 cancer immunotherapy pathway, phosphatase and tensin homolog (PTEN) and peroxisome proliferator-activated receptors (PPAR) signaling, and cytotoxic T-lymphocyte antigen 4 (CTLA-4) signaling in cytotoxic T lymphocytes, whereas several inflammation-related pathways were downregulated. Low CCR5/CCL5 expression was associated with increased benefit from cetuximab-FOLFOX treatment in the CALGB/SWOG 80405 trial, where significant treatment interaction was observed with biologic agents and chemotherapy backbone. CONCLUSIONS: Our data show a strong association between CCR5/CCL5 gene expression and distinct molecular features, gene expression profiles, TME cell infiltration, and treatment benefit in CRC. Targeting the CCR5/CCL5 axis may have clinical applications in selected CRC subgroups and may play a key role in developing and deploying strategies to modulate the immune TME for CRC treatment.

Impact of genetic variants involved in the lipid metabolism pathway on progression free survival in patients receiving bevacizumab-based chemotherapy in metastatic colorectal cancer: a retrospective analysis of FIRE-3 and MAVERICC trials.

Background: Antiangiogenic drug (AAD)-triggered oxygen and nutrient depletion through suppression of angiogenesis switches glucose-dependent to lipid-dependent metabolism. Blocking fatty acid oxidation can enhance AAD-mediated anti-tumor effects in colorectal cancer (CRC). Therefore, we hypothesised that genetic variants in the lipid metabolism pathway may predict clinical outcomes [overall response rate (ORR), overall survival (OS) and progression-free survival (PFS)] in metastatic CRC (mCRC) patients receiving bevacizumab-based first-line treatment. Methods: Genomic DNA from blood samples of patients enrolled in FIRE-3 (a global, randomised, open-label, phase 3 trial, between 2007-6-23 and 2012-9-19, discovery cohort: FOLFIRI/bevacizumab arm, n = 107; control cohort: FOLFIRI/cetuximab arm, n = 129) and MAVERICC (a global, randomised, open-label, phase II study, between 2011-8 and 2015-7, in United States, Canada, Estonia, Ireland, Switzerland, Norway, and Portugal. Validation cohort: FOLFIRI/bevacizumab arm, n = 163) trials, was genotyped using the OncoArray-500 K beadchip panel. The impact on OS and PFS of 17 selected SNPs in 7 genes involved in the lipid metabolism pathway (CD36, FABP4, LPCAT1/2, CPT1A, FASN, ACACA) was analysed using Kaplan-Meier curves, the log-rank test for univariate analyses and likelihood ratio tests of Cox proportional hazards regression parameters for multivariable analyses. ORR and SNP associations were evaluated using Chi-square or Fisher's exact tests. Findings: In the discovery cohort, patients with FASN rs4485435 any C allele (n = 21) showed significantly shorter PFS (median PFS: 8.69 vs 13.48 months) compared to carriers of G/G (n = 62) in multivariable (HR = 2.87; 95%CI 1.4-5.9; p = 0.00675) analysis. These data were confirmed in the validation cohort in multivariable analysis (HR = 2.07, 95%CI: 1.15-3.74; p = 0.02), but no association was observed in the cetuximab cohort of FIRE-3. In the comparison of bevacizumab vs cetuximab arm in FIRE-3, a significant interaction was shown with FASN rs4485435 (p = 0.017) on PFS. Interpretation: Our study demonstrates for the first time, to our knowledge, that FASN polymorphisms may predict outcome of bevacizumab-based treatment in patients with mCRC. These findings support a possible role of the lipid metabolism pathway in contributing to resistance to anti-VEGF treatment. Funding: This work was supported by the National Cancer Institute [P30CA 014089 to H.-J.L.], Gloria Borges WunderGlo Foundation, Dhont Family Foundation, Victoria and Philip Wilson Research Fund, San Pedro Peninsula Cancer Guild, Ming Hsieh Research Fund, Eddie Mahoney Memorial Research Fund, Shanghai Sailing Program (22YF1407000), China National Postdoctoral Program for Innovative Talents (BX20220084), China Postdoctoral Science Foundation (2022M710768), National Natural Science Foundation of China (82202892).

Mutational analysis of microsatellite-stable gastrointestinal cancer with high tumour mutational burden: a retrospective cohort study.

BACKGROUND: Genomic signatures contributing to high tumour mutational burden (TMB-H) independent from mismatch-repair deficiency (dMMR) or microsatellite instability-high (MSI-H) status are not well studied. We aimed to characterise molecular features of microsatellite stable (MSS) TMB-H gastrointestinal tumours. METHODS: Molecular alterations of 48 606 gastrointestinal tumours from Caris Life Sciences (CARIS) identified with next-generation sequencing were compared among MSS-TMB-H, dMMR/MSI-H, and MSS-TMB-low (L) tumours, using χ2 or Fisher's exact tests. Antitumour immune response within the tumour environment was predicted by analysing the infiltration of immune cells and immune signatures using The Cancer Genome Atlas database. The Kaplan-Meier method and the log-rank test were used to evaluate the impact of gene alterations on the efficacy of immune checkpoint inhibitors in MSS gastrointestinal cancers from the CARIS database, a Memorial Sloan Kettering Cancer Center cohort, and a Peking University Cancer Hospital cohort. FINDINGS: MSS-TMB-H was observed in 1600 (3·29%) of 48 606 tumours, dMMR/MSI-H in 2272 (4·67%), and MSS-TMB-L in 44 734 (92·03%). Gene mutations in SMAD2, MTOR, NFE2L2, RB1, KEAP1, TERT, and RASA1 might impair antitumour immune response despite TMB-H, while mutations in 16 other genes (CDC73, CTNNA1, ERBB4, EZH2, JAK2, MAP2K1, MAP2K4, PIK3R1, POLE, PPP2R1A, PPP2R2A, PTPN11, RAF1, RUNX1, STAG2, and XPO1) were related to TMB-H with enhanced antitumour immune response independent of dMMR/MSI-H, constructing a predictive model (modified TMB [mTMB]) for immune checkpoint inhibitor efficacy. Patients with any mutation in the mTMB gene signature, in comparison with patients with mTMB wildtype tumours, showed a superior survival benefit from immune checkpoint inhibitors in MSS gastrointestinal cancers in the CARIS cohort (n=95, median overall survival 18·77 months [95% CI 17·30-20·23] vs 7·03 months [5·73-8·34]; hazard ratio 0·55 [95% CI 0·31-0·99], p=0·044). In addition, copy number amplification in chromosome 11q13 (eg, CCND1, FGF genes) was more prevalent in MSS-TMB-H tumours than in the dMMR/MSI-H or MSS-TMB-L subgroups. INTERPRETATION: Not all mutations related to TMB-H can enhance antitumour immune response. More composite biomarkers should be investigated (eg, mTMB signature) to tailor treatment with immune checkpoint inhibitors. Our data also provide novel insights for the combination of immune checkpoint inhibitors and drugs targeting cyclin D1 or FGFs. FUNDING: US National Cancer Institute, Gloria Borges WunderGlo Foundation, Dhont Family Foundation, Gene Gregg Pancreas Research Fund, San Pedro Peninsula Cancer Guild, Daniel Butler Research Fund, Victoria and Philip Wilson Research Fund, Fong Research Project, Ming Hsieh Research Fund, Shanghai Sailing Program, China National Postdoctoral Program for Innovative Talents, China Postdoctoral Science Foundation, National Natural Science Foundation of China.

Genetic variants involved in the cGAS-STING pathway predict outcome in patients with metastatic colorectal cancer: Data from FIRE-3 and TRIBE trials.

BACKGROUND: The activation of stimulator of interferon genes (STING) was reported to enhance cetuximab-mediated natural killer cell activation and dendritic cell maturation. Polymorphisms in genes in the cyclic GMP-AMP synthase (cGAS)-STING pathway may affect innate immune response. Therefore, we hypothesised that genetic variants in the cGAS-STING pathway may predict the efficacy of cetuximab-based treatment in patients with metastatic colorectal cancer. METHODS: Genomic DNA from blood samples of patients enrolled in FIRE-3 (cetuximab arm, n = 129; bevacizumab arm, n = 107) and TRIBE (bevacizumab arm, n = 215) was genotyped using the OncoArray-500K bead chip panel. Seven selected single nucleotide polymorphisms in 3 genes (cGAS, STING and interferon B1 (IFNB1)) were analysed for the association with overall survival and progression-free survival. RESULTS: In the cetuximab cohort, patients with STING rs1131769 any T allele showed significantly shorter overall survival (36.3 versus 56.1 months) than carriers of C/C in both univariate [hazard ratio (HR) = 2.08; 95% confidence interval (CI): 1.06-4.07; P = 0.03] and multivariate (HR = 2.98; 95% CI: 1.35-6.6; P = 0.0085) analyses; patients carrying IFNB1 rs1051922 G/A and A/A genotype showed a significantly shorter progression-free survival than carriers of G/G allele in both univariate (G/A versus G/G, 10.2 versus 14.1 months, HR = 1.84; 95% CI 1.23-2.76; A/A versus G/G, 10.7 versus 14.1 months, HR = 2.19; 95% CI 0.97-4.96; P = 0.0077) and multivariate analyses (G/A versus G/G, HR = 2; 95% CI 1.22-3.3; A/A versus G/G, HR = 2.19, 95% CI 0.92-5.26, P = 0.02). These associations were not observed in the bevacizumab arm of FIRE-3 or TRIBE. CONCLUSION: These results suggest for the first time that germline polymorphisms in STING and IFNB1 genes may predict the outcomes of cetuximab-based treatment in patients with metastatic colorectal cancer.

Germline Polymorphisms in Genes Involved in the Antioxidant System Predict the Efficacy of Cetuximab in Metastatic Colorectal Cancer Patients Enrolled in FIRE-3 Trial.

BACKGROUND: Reactive oxygen species activate EGFR/RAS/MAPK signaling either through the inactivation of phosphatases or by direct oxidation of kinases. We hypothesized that functional single-nucleotide polymorphisms (SNPs) in antioxidant genes link to the efficacy of cetuximab in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: We analyzed genomic and clinical data from FIRE-3, a phase III trial comparing cetuximab and bevacizumab along with FOLFIRI in untreated mCRC patients. Genomic DNA extracted from blood samples was genotyped. Thirteen functional SNPs in antioxidant genes were tested for associations with clinical outcomes. RESULTS: In total, 236 patients were included (FOLFIRI/cetuximab arm, n = 129; FOLFIRI/bevacizumab arm, n = 107). In univariate analysis, two SNPs (TXN2 rs4821494 and GPX4 rs4807542) were significantly associated with overall survival (OS) in the FOLFIRI/cetuximab arm. Multivariate analysis confirmed the significant association of TXN2 rs4821494 (T/T vs. any G allele, hazard ratio = 2.47, 95% confidence interval = 1.06-5.72, P = .03). In the FOLFIRI/bevacizumab arm, no SNPs were significantly associated with clinical outcomes. Treatment-by-SNP interaction test confirmed the predictive value of TXN2 rs4821494 (OS: P = .03). CONCLUSION: TXN2 rs4821494 involved in the antioxidant system may predict the efficacy of cetuximab-based first-line chemotherapy in mCRC, warranting further validation studies.

Germline polymorphisms in genes maintaining the replication fork predict the efficacy of oxaliplatin and irinotecan in patients with metastatic colorectal cancer.

BACKGROUND: The TIMELESS-TIPIN complex protects the replication fork from replication stress induced by chemotherapeutic drugs. We hypothesised genetic polymorphisms of the TIMELESS-TIPIN complex may affect the response, progression-free survival (PFS), and overall survival (OS) of cytotoxic drugs in patients with metastatic colorectal cancer (mCRC). METHODS: We analysed data from the MAVERICC trial, which compared FOLFOX/bevacizumab and FOLFIRI/bevacizumab in untreated patients with mCRC. Genomic DNA extracted from blood samples was genotyped using an OncoArray. Eight functional single nucleotide polymorphisms (SNPs) in TIMELESS and TIPIN were tested for associations with clinical outcomes. RESULTS: In total, 324 patients were included (FOLFOX/bevacizumab arm, n = 161; FOLFIRI/bevacizumab arm, n = 163). In the FOLFOX/bevacizumab arm, no SNPs displayed confirmed associations with survival outcomes. In the FOLFIRI/bevacizumab arm, TIMELESS rs2291739 was significantly associated with OS in multivariate analysis (G/G vs. any A allele, hazard ratio = 3.06, 95% confidence interval = 1.49-6.25, p = 0.004). TIMELESS rs2291739 displayed significant interactions with treatment regarding both PFS and OS. CONCLUSIONS: TIMELESS rs2291739 might have different effects on therapeutic efficacy between oxaliplatin- and irinotecan-based chemotherapies. Upon further validation, our findings may be useful for personalised approaches in the first-line treatment of mCRC.

Molecular characteristics and clinical outcomes of patients with Neurofibromin 1-altered metastatic colorectal cancer.

Loss-of-function alterations of Neurofibromin 1 (NF1) activate RAS, a driver of colorectal cancer. However, the clinical implications of NF1 alterations are largely unknown. We performed a comprehensive molecular profiling of NF1-mutant colorectal cancer using data from 8150 patients included in a dataset of commercial CLIA-certified laboratory (Caris Life Sciences). In addition, NF1 expression levels were tested for associations with clinical outcomes using data from 431 patients in the CALGB/SWOG 80405 trial. In the Caris dataset, 2.2% of patients had pathogenic or presumed pathogenic NF1 mutations. NF1-mutant tumors more frequently harbored PIK3CA (25.0% vs. 16.7%) and PTEN mutations (24.0% vs. 4.2%) than wild type tumors. Gene set enrichment analysis revealed that MAPK and PI3K pathway signatures were enriched in NF1-mutant tumors. In the CALGB/SWOG 80405 cohort, low NF1 expression was associated with poor prognosis, and high NF1 expression was associated with better efficacy of cetuximab than bevacizumab. Together, we revealed concurrent genetic alterations in the PI3K pathways in NF1-mutant tumors, suggesting the need to simultaneously block MAPK and PI3K pathways in treatment. The potential of NF1 alteration as a novel biomarker for targeted therapy was highlighted, warranting further investigations in clinical settings.

Large-scale analysis of KMT2 mutations defines a distinctive molecular subset with treatment implication in gastric cancer.

Frequent mutations of genes in the histone-lysine N-methyltransferase 2 (KMT2) family members were identified in gastric cancers (GCs). Understanding how gene mutations of KMT2 family affect cancer progression and tumor immune microenvironment may provide new treatment strategies. A total of 1245 GCs were analyzed using next-generation sequencing, whole transcriptome sequencing, immunohistochemistry (Caris Life Sciences, Phoenix, AZ). The overall mutation rate of genes in the KMT2 family was 10.6%. Compared to KMT2-wild-type GCs, genes involved in epigenetic modification, receptor tyrosine kinases/MAPK/PI3K, and DNA damage repair (DDR) pathways had higher mutation rates in KMT2-mutant GCs (p < 0.05). Significantly higher rates of high tumor mutational burden, microsatellite instability-high/mismatch-repair deficiency (dMMR), and PD-L1 positivity were observed in KMT2-mutant GCs (p < 0.01), compared to KMT2-wild-type GCs. The association between PD-L1 positivity and KMT2 mutations remained significant in the proficient-MMR and microsatellite stable subgroup. Based on transcriptome data from the TCGA, cell cycle, metabolism, and interferon-α/ß response pathways were significantly upregulated in KMT2-mutant GCs than in KMT2-wild-type GCs. Patients with KMT2 mutation treated with immune checkpoint inhibitors had longer median overall survival compared to KMT2-wild-type patients with metastatic solid tumors (35 vs. 16 months, HR = 0.73, 95% CI: 0.62-0.87, p = 0.0003). In conclusion, this is the largest study to investigate the distinct molecular features between KMT2-mutant and KMT2-wild-type GCs to date. Our data indicate that GC patients with KMT2 mutations may benefit from ICIs and drugs targeting DDR, MAPK/PI3K, metabolism, and cell cycle pathways.

Germ line polymorphisms of genes involved in pluripotency transcription factors predict efficacy of cetuximab in metastatic colorectal cancer.

BACKGROUND: Cancer stem cells (CSCs) are primarily maintained by a network of pluripotency transcription factors (PTFs). Given a close relationship of CSC regulation with epidermal growth factor receptor and vascular endothelial growth factor signalling, we investigated whether single-nucleotide polymorphisms (SNPs) in PTF genes are related to the efficacy of cetuximab and/or bevacizumab in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Genomic and clinical data from three independent clinical trial cohorts were tested: cetuximab cohort (FOLFIRI/cetuximab arm in FIRE-3, n = 129), bevacizumab cohort 1 (FOLFIRI/bevacizumab arm in FIRE-3, n = 107) and bevacizumab cohort 2 (FOLFIRI/bevacizumab arm in TRIBE, n = 215). Genomic DNA extracted from blood samples was genotyped, and ten SNPs were tested for association with clinical outcomes. RESULTS: In the cetuximab cohort, four SNPs were significantly associated with progression-free survival in univariate analysis: NANOG rs11055767 (any A allele vs C/C, hazard ratio [HR] = 0.62, 95% confidence interval [CI] = 0.42-0.94, p = 0.02), NANOG rs10744044 (any A allele vs G/G, HR = 0.59, 95% CI = 0.39-0.90, p = 0.01), NANOGP8 rs2168958 (any C allele vs A/A, HR = 2.12, 95% CI = 1.36-3.29, p < 0.001) and NANOGP8 rs2279066 (any C allele vs T/T, HR = 1.80, 95% CI = 1.06-1.68, p = 0.03). Multivariate analysis confirmed the significant associations for NANOGP8 rs2168958 and NANOGP8 rs2279066. In either bevacizumab cohort, no significant associations were observed in univariate analysis. CONCLUSIONS: Germ line polymorphisms in the PTF genes could be predictive markers for cetuximab in mCRC.

The Landscape of Alterations in DNA Damage Response Pathways in Colorectal Cancer.

PURPOSE: Defective DNA damage response (DDR) is a hallmark of cancer leading to genomic instability and is associated with chemosensitivity. Although the mismatch repair system has been extensively studied, the clinical implications of other mechanisms associated with DDR alterations in patients with colorectal cancer remain unclear. This study aimed to understand DDR pathways alterations and their association with common clinical features in patients with colorectal cancer. EXPERIMENTAL DESIGN: Next-generation sequencing and whole-transcriptome sequencing were conducted using formalin-fixed paraffin-embedded samples submitted to a commercial Clinical Laboratory Improvement Amendments-certified laboratory. Samples with pathogenic or presumed pathogenic mutations in 29 specific DDR-related genes were considered as DDR-mutant (DDR-MT) and the remaining samples as DDR-wild type (DDR-WT). RESULTS: Of 9,321 patients with colorectal cancer, 1,290 (13.8%) were DDR-MT. The frequency of DDR-MT was significantly higher in microsatellite instability-high (MSI-H) cases than in microsatellite stable cases (76.4% vs. 9.5%). The DDR-MT genotype was higher in the right-sided, RAS-wild, BRAF-mutant, and CMS1 subgroups. However, these associations were primarily confounded by the distribution of MSI status. Compared with the DDR-WT tumors, the DDR-MT tumors had a higher mutational burden and gene expression levels in the immune-related pathway, which were independent of MSI status. CONCLUSIONS: We characterized a distinct subgroup of patients with colorectal cancer with tumors harboring mutations in the DDR-related genes. These patients more commonly had MSI-H tumors and exhibited an activated immune signature regardless of their tumor's MSI status. These findings warrant further investigations to develop personalized treatment strategies in this significant subgroup of patients with colorectal cancer.

RNA-Binding Protein Polymorphisms as Novel Biomarkers to Predict Outcomes of Metastatic Colorectal Cancer: A Meta-analysis from TRIBE, FIRE-3, and MAVERICC.

RNA-binding proteins (RBPs) regulate many posttranscriptional cellular activities. Accumulating evidence suggests associations between RBPs with colonic tumorigenesis and chemosensitivity. We investigated the prognostic and predictive values of SNPs of genes encoding RBPs in metastatic colorectal cancer (mCRC), using clinical and genomic data from three randomized clinical trials of standard first-line chemotherapy for mCRC (TRIBE, FIRE-3, and MAVERICC). Genomic DNA extracted from blood samples was genotyped using an OncoArray. We tested 30 candidate SNPs of 10 major RBP-related genes with additive models. Prognostic values were estimated by meta-analysis approach. Treatment-by-SNP interactions were tested to estimate predictive values for targeted drugs and cytotoxic backbone chemotherapies. This study included 884 patients. The meta-analysis revealed prognostic values of LIN28B rs314277 [HR, 1.26; 95% confidence interval (CI), 1.06-1.49, P = 0.005, FDR-adjusted P = 0.072 for overall survival (OS)] and LIN28B rs314276 (HR, 1.25; 95% CI, 1.08-1.44, P = 0.002, FDR-adjusted P = 0.062 for OS). Although some SNPs showed potentially predictive values, these associations were not confirmed after FDR adjustment. In conclusion, the results of this study are warranting additional studies to provide the evidence that RBP-related SNPs may be associated with the prognosis of patients with mCRC treated with standard first-line chemotherapies. In addition, further studies are warranted to study the predictive value.

Immunogenic cell death pathway polymorphisms for predicting oxaliplatin efficacy in metastatic colorectal cancer.

BACKGROUND: Immunogenic cell death (ICD) is a tumor cell death involving both innate and adaptive immune responses. Given published findings that oxaliplatin, but not irinotecan, drives ICD, we investigated whether single nucleotide polymorphisms (SNPs) in the ICD pathway are associated with the efficacy of oxaliplatin-based chemotherapy in metastatic colorectal cancer (mCRC). METHODS: Two randomized clinical trials data were analyzed: discovery cohort, FOLFOX/bevacizumab arm (MAVERICC); validation cohort, FOLFOXIRI/bevacizumab arm (TRIBE); and two control cohorts, FOLFIRI/bevacizumab arms (both trials). Genomic DNA extracted from blood samples was genotyped. Ten SNPs in the ICD pathway were tested for associations with clinical outcomes. RESULTS: In total, 648 patients were included. In the discovery cohort, three SNPs were significantly associated with clinical outcomes in univariate analysis: CALR rs1010222 with progression-free survival (G/G vs any A, HR=0.61, 95% CI 0.43-0.88), ANXA1 rs1050305 with overall survival (OS) (A/A vs any G, HR=1.87, 95% CI 1.04-3.35), and LRP1 rs1799986 with OS (C/C vs any T, HR=1.69, 95% CI 1.07-2.70). Multivariate analysis confirmed the trend, but statistical significance was not reached. In the validation cohort, ANXA1 rs1050305, and LRP1 rs1799986 were validated to have the significant associations with clinical outcome. No significant associations of these SNPs were observed in the two control cohorts. Treatment-by-SNP interaction test confirmed the predictive values. CONCLUSIONS: The predictive utility of ICD-related SNPs for the efficacy of oxaliplatin-based chemotherapy was demonstrated, warranting further validation studies to be translated into personalized treatment strategies using conventional cytotoxic agents in mCRC.

Molecular Characterization of Appendiceal Goblet Cell Carcinoid.

Goblet cell carcinoid (GCC) is a distinct subtype of appendiceal neoplasm that exhibits unique clinical and pathologic features. We aimed to reveal the molecular profiles of GCC compared with other appendiceal tumors, such as adenocarcinomas and neuroendocrine tumors. A total of 495 appendiceal tumor samples (53 GCCs, 428 adenocarcinomas, and 14 neuroendocrine tumors) were tested with next-generation sequencing (NGS) on a 592-gene panel and IHC. Microsatellite instability (MSI)/mismatch repair (MMR) status was tested with a combination of NGS, IHC, and fragment analyses. Tumor mutational burden (TMB) was evaluated by NGS, and PD-L1 expression was tested by IHC (SP142). The most prevalent mutated genes within GCCs were TP53 (24.0%), ARID1A (15.4%), SMAD4 (9.4%), and KRAS (7.5%). Pathway-specific alterations were dominantly observed in cell cycle, MAPK, epigenetic, and TGFß signaling pathways. GCCs as compared with adenocarcinomas exhibited significantly lower mutation rates in KRAS, GNAS, and APC, and significantly higher mutation rates in CDH1, CHEK2, CDC73, ERCC2, and FGFR2 GCCs as compared with neuroendocrine tumors showed significantly lower mutation rates in KRAS, APC, BRCA2, and FANCA In GCCs, MSI high/MMR deficient, TMB high (≥17 mutations/Mb), and PD-L1 expression were seen in 0.0%, 0.0%, and 2.0% of tumors, respectively. No significant differences were observed in any immunotherapy-related markers examined when compared with adenocarcinomas and neuroendocrine tumors. In conclusion, GCCs had considerably distinct mutational profiles compared with appendiceal adenocarcinomas and neuroendocrine tumors. Understanding these molecular characteristics may be critical for the development of novel and more effective treatment strategies for GCC.

Retrospective Assessment of the Diagnostic Accuracy of the Depth of Invasion by Narrow Band Imaging Magnifying Endoscopy in Patients with Superficial Esophageal Squamous Cell Carcinoma.

PURPOSE: Treatment strategies for superficial esophageal squamous cell carcinoma (S-ESCC) are determined mainly on the basis of the depth of invasion. We retrospectively studied the accuracy of the depth of tumor invasion, comprehensively assessed using the Japan Esophageal Society (JES) classification. METHODS: The study group comprised 256 patients who underwent narrow band imaging (NBI) magnifying endoscopy, and endoscopic submucosal dissection for S-ESCC. The depth of invasion of S-ESCC was classified into three groups: EP/LPM, MM/SM1, and SM2. The following variables were studied retrospectively: (1) the diagnostic accuracy of non-magnifying white-light endoscopy, (2) the diagnostic accuracy of type B vessels, (3) the diagnostic accuracy of avascular area (AVA), (4) the diagnostic accuracy of the JES classification, and (5) the diagnostic accuracy of comprehensive diagnosis. The depth of invasion was assessed by white-light non-magnifying endoscopy, followed by NBI magnifying endoscopy. RESULTS: The positive predictive value (PPV) of white-light non-magnifying endoscopy was 86% for EP/LPM, 53% MM/SM1, and 74% for SM2. The PPV of the diagnosis of type B vessels was 93% for EP/LPM, 62% for MM/SM1, and 74% for SM2. The PPV of the AVA diagnosis was 73% for EP/LPM, 89% for MM/SM1, and 100% for SM2. The PPV of diagnosis according to the JES classification was 93% for EP/LPM, 65% for MM/SM1, and 77% for SM2. The PPV of the comprehensive diagnosis was 94% for EP/LPM, 63%, for MM/SM1, and 75% for SM2. CONCLUSIONS: The additional use of NBI magnifying endoscopy can enhance the diagnostic accuracy of the depth of invasion in patients with S-ESCC.

Feasibility of definitive chemoradiation therapy with nedaplatin and 5-fluorouracil in elderly patients with esophageal squamous cell carcinoma: A retrospective study.

PURPOSE: This study was designed to retrospectively analyze the safety and efficacy of chemoradiation therapy with nedaplatin and 5-fluorouracil in elderly patients with esophageal squamous cell carcinoma. METHODS AND MATERIALS: Eligible patients were aged 76 years or older, had a histopathologic diagnosis of esophageal squamous cell carcinoma, and were treated at the Kitasato University Hospital between January 2010 and March 2016. Chemotherapy consisted of nedaplatin in an intravenous dose of 90 mg/m2 on day 1 and 5-fluorouracil in an intravenous dose of 800 mg/m2 on days 1 to 5, repeated every 4 weeks for 2 cycles. Radiation therapy consisted of 50.4 Gy in 28 fractions for thoracic tumors and 61.2 Gy for cervical tumors. RESULTS: Twenty-five patients were studied. Patient characteristics were as follows: median age 79 years (range, 76-85 years), clinical stage I/II/III/IV (7/8/8/2, respectively), and surgically resectable/unresectable (17/8, respectively). The completion rates of radiation therapy and chemoradiation therapy were 100% and 84%, respectively. Grade ≥3 acute toxicities included neutropenia (76%), leukopenia (72%), thrombocytopenia (32%), anemia (28%), anorexia (32%), oral mucositis (20%), febrile neutropenia (12%), and esophagitis (8%). Grade ≥3 late toxicities included esophageal stenosis (12%) and pleural effusion (4%). The complete response rate was 64%. In the median follow-up period of 18.9 months, the 1-year overall survival rate was 68%. CONCLUSIONS: Definitive chemoradiation therapy with nedaplatin and 5-fluorouracil may be a feasible treatment option for elderly patients with esophageal squamous cell carcinoma.

Long-term outcomes of patients with early gastric cancer found to have lesions for which endoscopic treatment is not indicated on histopathological evaluation after endoscopic submucosal dissection.

BACKGROUND: Gastric cancer treatment guidelines recommend additional surgery as the standard treatment for lesions for which endoscopic submucosal dissection (ESD) is not indicated. However, the incidence of lymph-node metastasis is low in most patients. METHODS AND MATERIALS: The study comprised 231 patients (231 lesions) who underwent ESD for early gastric cancer (EGC) in our hospital from September 2002 through March 2015 and were found to have lesions for which endoscopic treatment is not indicated on histopathological evaluation after ESD. The patients were divided into the additional operation group and the follow-up group, and long-term outcomes were studied retrospectively. Risk factors for metastasis and recurrence were also studied (capture rate, 98.7%). RESULTS: The median follow-up was 48 months. There were 174 men and 57 women with a median age of 72 years. The additional operation group comprised 118 patients, and the follow-up group comprised 113 patients. The rates of 5-year cause-specific survival and 5-year overall survival were significantly higher in the additional operation group (100 and 96.0%, respectively) than in the follow-up group (92.6 and 73.3%, respectively; p = 0.010, p < 0.001). In the follow-up group, 5 patients (4.4%) died of gastric cancer (p = 0.021). Among elderly patients 75 years or older, long-term outcomes did not differ significantly between the groups. Sixteen patients had metastasis or recurrence, and the presence of lymphatic involvement was an independent risk factor for metastasis, recurrence, or both (p = 0.003; odds ratio 10.594; 95% confidence interval 2.294-48.927). CONCLUSIONS: In patients with EGC who are confirmed to have lesions for which endoscopic treatment is not indicated on histopathological evaluation after ESD, additional surgery should be aggressively performed if the patient can tolerate such treatment. In elderly patients aged 75 years or older and patients with serious underlying diseases, follow-up observation was suggested to be one option in patients who give informed consent after receiving an explanation of the risk of recurrence.

Correction to: Long-term outcomes of patients with early gastric cancer found to have lesions for which endoscopic treatment is not indicated on histopathological evaluation after endoscopic submucosal dissection.

In Table 1, the second item in the right-hand column "Extra-indication" should be changed to "Out of indication". The correct version of Table 1 is displayed.

Clinical Outcomes in Patients with Cancer of Unknown Primary Site Treated By Gastrointestinal Oncologists.

OBJECTIVE: To evaluate the clinical outcomes in patients with cancer of an unknown primary site (CUP), who were treated by gastrointestinal oncologists. METHODS: We retrospectively studied 29 patients with CUP who were presented at the Department of Gastroenterology, Kitasato University Hospital from October 2005 to October 2013, and were treated by the gastrointestinal oncologists. The patients were divided into two groups, namely chemotherapy group and symptomatic therapy group, and the clinical characteristics and survival times were compared. The clinical course was studied according to the histologic type (adenocarcinoma or non-adenocarcinoma), prognostic subset (favorable or unfavorable), and the presence or absence of chemotherapy. RESULTS: The chemotherapy group comprised 19 patients, and the symptomatic therapy group comprised 10 patients. The median survival time was 11 months in the chemotherapy group and 3 months in the symptomatic therapy group. Twenty-two patients had adenocarcinoma, and 7 had non-adenocarcinoma. Of the 22 patients with adenocarcinoma, 2 belonged to the favorable prognostic subset and received chemotherapy. One of these patients died of cancer at 47 months, and the other was alive and disease free at 58 months. Among the 20 patients with adenocarcinoma in the unfavorable prognostic subset, 16 received chemotherapy and had a median survival of 16 months. Seven (44%) of these patients survived for at least 21 months, and 3 patients who could receive 3 or more regimens survived for at least 46 months. CONCLUSION: It might be appropriate for gastrointestinal oncologists to treat CUP on the basis of clinical experience, depending on the situation.

Different clinical characteristics associated with acute bleeding and delayed bleeding after endoscopic submucosal dissection in patients with early gastric cancer.

BACKGROUND/AIMS: Few studies have classified risk factors according to the onset time of bleeding after endoscopic submucosal dissection (post-ESD bleeding). METHODS: We studied 1767 consecutive lesions in patients who underwent ESD for early gastric cancer from December 2006 through June 2016. Patients who had a remnant stomach or who had undergone reconstruction with a gastric tube were excluded. Post-ESD bleeding was classified into acute bleeding (0-5 days after ESD) and delayed bleeding (6 or more days after ESD), and the risk factors for each type of bleeding were compared. RESULTS: Post-ESD bleeding occurred in 150 (8.5%) of 1767 lesions. Bleeding was acute in 129 lesions (7.3%) and delayed in 21 (1.2%). Acute post-ESD bleeding was frequently associated with lesions located in the distal stomach, expanded indications or non-indicated lesions, a specimen diameter of ≥40 mm, and antithrombotic therapy. Delayed post-ESD bleeding was often associated with lesions located in the proximal stomach, hemodialysis, and antithrombotic therapy. Among 334 lesions in patients who received antithrombotic therapy, post-ESD bleeding occurred in 47 lesions (14.1%). Independent risk factors for post-ESD bleeding were a specimen diameter of ≥40 mm and treatment with 2 or more antithrombotic agents. CONCLUSIONS: Acute post-ESD bleeding and delayed post-ESD bleeding were associated with different clinical characteristics. Antithrombotic therapy is a risk factor for post-ESD bleeding in both the acute and delayed phases.

Delayed perforation after endoscopic submucosal dissection for early gastric cancer: Clinical features and treatment.

Perforation is an important procedural complication of endoscopic submucosal dissection (ESD) for early gastric cancer. Although the incidence of delayed perforation after ESD is low, extreme caution is necessary because many cases require surgical intervention. Among 1984 lesions of early gastric cancer treated in our hospital by ESD in 1588 patients from September 2002 through March 2015, delayed perforation developed in 4 patients (4 lesions, 0.25%). A diagnosis of delayed perforation requires prompt action, including surgical intervention when required.