Genomic profiling of small bowel adenocarcinoma: a pooled analysis from 3 databases.

BACKGROUND: Small bowel adenocarcinoma is a rare disease. The genomic profiling tumours according to clinical characteristics and its impact on the prognosis remains unclear. METHODS: A pooled analysis of clinical data, genomic profiling and MisMatch Repair (MMR) status from three databases was performed. RESULTS: A total of 188 tumour samples were analysed. A predisposing disease was reported in 22.3%, mainly Lynch syndrome and Crohn's disease. The tumours were localized in 80.2% and metastatic in 18.8%. The most frequent mutations were KRAS (42.0%) among them 7/79 are G12C, TP53 (40.4%), APC (19.1%), PIK3CA (18.6%), SMAD4 (12.8%) and ERBB2 (9.6%). Mutation distribution differed according to predisposing disease for TP53, ERBB2, IDH1, FGFR3, FGFR1 and KDR. KRAS and SMAD4 mutations were more frequent in metastatic tumour, whereas ERBB2 mutations were absent in metastatic tumour. For localized tumour, APC mutation was independently associated with a poor overall survival (OS) (p = 0.0254). 31.8% of localized tumours and 11.3% of metastatic tumours were dMMR (29.8% of the entire cohort). A dMMR status was associated with a better OS (HR = 0.61 [0.39-0.96], p = 0.0316). CONCLUSIONS: There is a different genomic profile according to the stage and predisposing disease. dMMR and APC mutation in localized tumour predict a better prognosis.

Outcome on Mesenteric Mass Response of Small-Intestinal Neuroendocrine Tumors Treated by 177Lu-DOTATATE Peptide Receptor Radionuclide Therapy: The MesenLuth Study, a National Study from the French Group of Endocrine Tumors and Endocan-RENATEN Network.

A mesenteric mass (MM), characterized by fibrotic reaction, is present in most small-intestinal neuroendocrine tumors (SI-NETs). 177Lu-DOTATATE peptide receptor radionuclide therapy (PRRT) has shown its efficacy in patients with progressive SI-NETs. However, because of specific tissue characteristics of desmoplastic MMs, we hypothesize that these lesions may be refractory to 177Lu-DOTATATE PRRT. Methods: From the national French Groupe d'étude des Tumeurs Endocrines database, we identified patients with an advanced SI-NET and a MM (≥2 cm with a retractile aspect) of a SI-NET treated by at least 1 course of 177Lu-DOTATATE PRRT. The primary endpoint was a MM objective response rate (ORR) of less than 5%. Secondary endpoints were metabolic response, MM-related safety, and clinical response, as well as MM progression-free survival (PFS) and non-MM PFS. Results: In total, 52 patients were included. The MM ORR was 4% (n = 2), and the non-MM ORR was 8% (n = 4). No patient had a MM metabolic response, and the non-MM metabolic response rate was 12% (n = 6). Among the 26 patients with baseline MM-related symptoms, 46% had a clinical response. Four patients presented with gastrointestinal complications during PRRT. The median MM-related PFS was not reached, and the non-MM PFS was 50.3 mo (95% CI, 38.2-61.7 mo). Conclusion: This study confirms that 177Lu-DOTATATE PRRT does not lead to morphologic response on MMs (ORR < 5%). However, it allows MM stability, with few MM-related side effects, and has a relevant impact on MM-related symptoms.

The Need for Centralization for Small Intestinal Neuroendocrine Tumor Surgery: A Cohort Study from the GTE-Endocan-RENATEN Network, the CentralChirSINET Study.

BACKGROUND: The concept of surgical centralization is becoming more and more accepted for specific surgical procedures. OBJECTIVE: The aim of this study was to evaluate the relationship between procedure volume and the outcomes of surgical small intestine (SI) neuroendocrine tumor (NET) resections. METHODS: We conducted a retrospective national study that included patients who underwent SI-NET resection between 2019 and 2021. A high-volume center (hvC) was defined as a center that performed more than five SI-NET resections per year. The quality of the surgical resections was evaluated between hvCs and low-volume centers (lvCs) by comparing the number of resected lymph nodes (LNs) as the primary endpoint. RESULTS: A total of 157 patients underwent surgery in 33 centers: 90 patients in four hvCs and 67 patients in 29 lvCs. Laparotomy was more often performed in hvCs (85.6% vs. 59.7%; p < 0.001), as was right hemicolectomy (64.4% vs. 38.8%; p < 0.001), whereas limited ileocolic resection was performed in 18% of patients in lvCs versus none in hvCs. A bi-digital palpation of the entire SI length (95.6% vs. 34.3%, p < 0.001), a cholecystectomy (93.3% vs. 14.9%; p < 0.001), and a mesenteric mass resection (70% vs. 35.8%; p < 0.001) were more often performed in hvCs. The proportion of patients with ≥8 LNs resected was significantly higher (96.3% vs. 65.1%; p < 0.001) in hvCs compared with lvCs, as was the proportion of patients with ≥12 LNs resected (87.8% vs. 52.4%). Furthermore, the number of patients with multiple SI-NETs was higher in the hvC group compared with the lvC group (43.3% vs. 25.4%), as were the number of tumors in those patients (median of 7 vs. 2; p < 0.001). CONCLUSIONS: Optimal SI-NET resection was significantly more often performed in hvCs. Centralization of surgical care of SI-NETs is recommended.

Adjuvant chemotherapy benefit according to T and N stage in small bowel adenocarcinoma: a large retrospective multicenter study.

BACKGROUND: Small bowel adenocarcinoma is a rare cancer, and the role of adjuvant chemotherapy for localized disease is still debated. METHODS: This retrospective multicenter study included all consecutive patients who underwent curative surgical resection for localized small bowel adenocarcinoma between 1996 and 2019 from 3 French cohort studies. Prognostic and predictive factors of adjuvant chemotherapy efficacy were analyzed for disease-free survival and overall survival. The inverse probability of treatment weighting method was applied in the Cox regression model using the propensity score derived from multivariable logistic regression. RESULTS: A total of 354 patients were included: median age, 63.5 years; duodenum location, 53.5%; and tumor stage I, II, and III in 31 (8.7%), 144 (40.7%), and 179 (50.6%) patients, respectively. The adjuvant chemotherapy was administered in 0 (0%), 66 (48.5%), and 143 (80.3%) patients with stage I, II, and III, respectively (P < .0001). In the subgroup analysis by inverse probability of treatment weighting method, a statistically significant disease-free survival and overall survival benefit in favor of adjuvant chemotherapy was observed in high-risk stage II (T4 and/or <8 lymph nodes examined) and III (T4 and/or N2) but not for low-risk stage II (T3 and ≥8 lymph nodes examined) and III (T1-3/N1) tumors (Pinteraction < .05). Furthermore, tumor location in jejunum and ileum was also a statistically significant predictive factor of response to adjuvant chemotherapy in stage II and III tumors (Pinteraction < .05). CONCLUSION: In localized small bowel adenocarcinoma, adjuvant chemotherapy seems to provide a statistically significant survival benefit for high-risk stage II and III tumors and for jejunum and ileum tumor locations.

Performance of a blood-based RNA signature for gemcitabine-based treatment in metastatic pancreatic adenocarcinoma.

Background: Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal cancer, and chemotherapy is a key treatment for advanced PDAC. Gemcitabine chemotherapy is still an important component of treatment; however, there is no routine biomarker to predict its efficacy. Predictive tests may help clinicians to decide on the best first-line chemotherapy. Methods: This study is a confirmatory study of a blood-based RNA signature, called the GemciTest. This test measures the expression levels of nine genes using real-time polymerase chain reaction (PCR) processes. Clinical validation was carried out, through a discovery and a validation phases, on 336 patients (mean 68.7 years; range, 37-88 years) for whom blood was collected from two prospective cohorts and two tumor biobanks. These cohorts included previously untreated advanced PDAC patients who received either a gemcitabine- or fluoropyrimidine-based regimen. Results: Gemcitabine-based treated patients with a positive GemciTest (22.9%) had a significantly longer progression-free survival (PFS) {5.3 vs. 2.8 months; hazard ratio (HR) =0.53 [95% confidence interval (CI): 0.31-0.92]; P=0.023} and overall survival (OS) [10.4 vs. 4.8 months; HR =0.49 (95% CI: 0.29-0.85); P=0.0091]. On the contrary, fluoropyrimidine-based treated patients showed no significant difference in PFS and OS using this blood signature. Conclusions: The GemciTest demonstrated that a blood-based RNA signature has the potential to aid in personalized therapy for PDAC, leading to better survival rates for patients receiving a gemcitabine-based first-line treatment.

Diagnostic performance and impact on patient management of [68Ga]Ga-DOTA-TOC PET/CT in colorectal neuroendocrine tumors derived from hindgut.

The main purpose of this retrospective study was to determine the diagnostic performance of [68Ga]Ga-DOTA-D-Phe1-Try3-octreotide(DOTA-TOC) positron emission tomography/computed tomography (PET/CT) in patients with well-differentiated colorectal Neuroendocrine Tumours (NETs) originating from the hindgut. The other aims were to assess the impact of the examination on patient management and to analyze the results of 2-[18F]FDG and/or 6-[18F]FDOPA PET/CT when they were performed. [68Ga]Ga-DOTA-TOC PET/CT and clinical data from 30 patients with biopsy-proven well-differentiated NETs originating from the hindgut were retrospectively reviewed and analyzed by comparing the [68Ga]Ga-DOTA-TOC PET/CT findings with pathological and/or follow-up data. We also compared the [68Ga]Ga-DOTA-TOC PET/CT results with 2-[18F]FDG and/or 6-[18F]FDOPA PET/CT results in 6 patients. The impact on management was determined in hindsight by comparing the patient management decided before and after the TEP examination based on data from multidisciplinary team meetings. On a patient basis, [68Ga]Ga-DOTA-TOC PET/CT was accurate in 30 of the 30 examinations. [68Ga]Ga-DOTA-TOC PET/CT correctly identified the primary tumor in all patients with primary tumors not resected before the examination and allowed the detection of unexpected distant metastases in 36% of the patients referred for initial staging. [68Ga]Ga-DOTA-TOC PET/CT findings affected patient management in 57% of cases with generally major intermodality changes. Intraindividual comparison of the results of the different PET radiopharmaceuticals showed a clear superiority of [68Ga]Ga-DOTA-TOC PET/CT considering both the number of lesions and the intensity of uptake. [68Ga]Ga-DOTA-TOC PET/CT is an accurate imaging modality for the assessment of well-differentiated colorectal NETs that highly impact patient management. Thus, we suggest that [68Ga]Ga-DOTA-TOC PET/CT be employed as a first choice for the assessment of these tumors in nuclear medicine.

Use of Proton Pump Inhibitors and Risk of Pancreatic Cancer: A Nationwide Case-Control Study Based on the French National Health Data System (SNDS).

BACKGROUND: Only a few studies investigated the association between proton pump inhibitor (PPI) use and pancreatic cancer, with inconsistent results. Moreover, these studies had a number of methodologic limitations. Our objective was to assess this association in a nationwide case-control study. METHODS: We used the French National Health Data System (SNDS), covering 99% of the French population since 2006. Incident cases of pancreatic cancer, identified between 2014 and 2018, were matched with up to four controls on year of birth, sex, frequency of hospitalization within 8 years prior to index date, and department of residence. Associations between PPIs and pancreatic cancer were estimated using conditional logistic regression models adjusted for sociodemographic characteristics, risk factors of pancreatic cancer (including diabetes mellitus, tobacco-related diseases, and morbid obesity), and other comorbidities. RESULTS: A total of 23,321 cases of pancreatic cancer (mean age, 69.8 years; 51.7% males) and 75,937 matched controls were included. Overall, 77.8% of cases and 75.5% of controls were PPI ever users. Ever (vs. never) PPI use was associated with an increased risk of pancreatic cancer [adjusted OR (aOR) = 1.05, 95% confidence interval (CI), 1.01-1.09]. A dose-response relationship was observed [1-30 cumulative defined daily dose (cDDD): aOR = 0.92, 95% CI, 0.87-0.97; 31-180 cDDD: aOR = 1.05, 95% CI, 1.00-1.11; 181-1,080 cDDD: aOR = 1.18, 95% CI, 1.12-1.24; >1,080 cDDD: aOR = 1.17, 95% CI, 1.10-1.23]. CONCLUSIONS: On the basis of these findings, a slight increase in the risk of pancreatic cancer associated with high cumulative doses of PPIs cannot be excluded. IMPACT: Given the overuse of PPIs, efforts should be continued to limit treatments to appropriate indications and durations.

FOLFIRINEC: a randomized phase II trial of mFOLFIRINOX vs platinum-etoposide for metastatic neuroendocrine carcinoma of gastroenteropancreatic or unknown origin.

BACKGROUND: Poorly differentiated neuroendocrine carcinomas (NEC) are rare diseases with a poor prognosis. Platinum-etoposide (PE) has been the recommended first-line treatment for decades. FOLFIRINEC (NCT04325425) is a national multicenter randomized phase II study which aims to challenge this standard regimen. METHODS: The primary objective is to compare the median progression-free survival (PFS) under mFOLFIRINOX versus PE. The secondary objectives are to evaluate the objective response rates (ORR), median overall survival (OS), safety and quality of life. The associated real-time translational study will establish a molecular profile for each patient enrolled. MAIN INCLUSION CRITERIA ARE: NEC of gastroenteropancreatic (GEP) or unknown origin, metastatic and RECIST 1.1 evaluable disease, tumor sample available and no contraindication to chemotherapy. Patients will be randomized 1:1 between PE every 21 days for 6-8 cycles and mFOLFIRINOX every 14 days for up to 12 cycles and stratified according to center, performance status, Ki67 and pathological subtype. This trial will randomize 218 patients (24 months of follow-up) to have 80% power to detect an improvement of the median PFS from 5 months under PE to 7.5 months under mFOLFIRINOX (HR of 0.67, α =5%, two-sided). An intermediate analysis is planned at 50% of events. Recruitment started on October 20, 2020.

Panel gene profiling of small bowel adenocarcinoma: Results from the NADEGE prospective cohort.

Small bowel adenocarcinoma (SBA) is a rare tumour. Large genomic analyses with prognostic assessments are lacking. The NADEGE cohort has enrolled 347 patients with all stage SBA from 2009 to 2012. Next-generation sequencing investigates the presence of 740 hotspot somatic mutations in a panel of 46 genes involved in carcinogenesis. The mismatch repair (MMR) status was assessed by immunochemistry. We have collected 196 tumour samples and 125 had conclusive results for mutation analysis. The number of mutations was 0 in 9.6% of tumours, only 1 in 32.0%, 2 in 26.4% and ≥3 in 32.0%. Overall, at least one genomic alteration was observed in 90.4% of tumour. The most frequent genomic alteration was in KRAS (44.0%), TP53 (38.4%), PIK3CA (20.0%), APC (18.4%), SMAD4 (14.4%) and ERBB2 (7.2%) genes. KRAS mutations were more frequent in synchronous metastatic tumours than in localised tumours (72.7% vs 38.2%, P = .003). There was no significant difference in the mutation rates according to primary location for the most frequently altered gene. ATM, FGFR3 and FGFR1 gene alterations were associated with Lynch syndrome and IDH1 mutations with Crohn disease. dMMR tumours were associated with younger age, localised tumours, less KRAS but more SMARCB1 mutations. No genomic alteration was associated with overall survival. There is a trend for better survival in patient with dMMR tumours. In conclusion, there is a different genomic alteration profile in SBA according to predisposing diseases. No association between genomic alterations and prognoses was observed except for a trend of better prognoses associated with dMMR.

Personalized four-category staging for predicting prognosis in patients with small bowel Adenocarcinoma: an international development and validation study.

BACKGROUND: Log odds of positive lymph nodes (LODDS) classification showed superiority over 8th edition N staging in predicting survival of small bowel adenocarcinoma (SBA) patients. The aim of this study was to develop and validate the Tumor, LODDS, and Metastasis (TLM) staging of SBA. METHODS: Totally 1789 SBA patients from the Surveillance, Epidemiology, and End Results (SEER) database between 1988-2010, 437 patients from SEER database between 2011-2013 and 166 patients from multicenters were categorized into development, validation and test cohort, respectively. The TLM staging was developed in the development cohort using Ensemble Algorithm for Clustering Cancer Data (EACCD) method. C-index was used to assess the performance of the TLM staging in predicting cancer-specific survival (CSS) and was compared with the traditional 8th edition TNM staging. FINDINGS: Four-category TLM staging designed for the development cohort showed higher discriminatory power than TNM staging in predicting CSS in the development cohort (0.682 vs. 0.650, P < 0.001), validation cohort (0.682 vs. 0.654, P = 0.022), and test cohort (0.659 vs. 0.611, P = 0.023), respectively. TLM staging continued to show its higher predictive efficacy than the 8th TNM in TNM stage II/III patients or in patients with lymph node yield less than 8. INTERPRETATION: TLM staging showed a better prognostic performance than the 8th TNM staging especially TNM stage II/III or patients with lymph node yield less than 8 and therefore, could serve to complement the TNM staging in patients with SBA. FUNDING: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.

Small bowel adenocarcinoma: Results from a nationwide prospective ARCAD-NADEGE cohort study of 347 patients.

Small bowel adenocarcinoma (SBA) is a rare tumour. We conducted a prospective cohort to describe the prevalence, survival and prognostic factors in unselected SBA patients. The study enrolled patients with all stages of newly diagnosed or recurrent SBA at 74 French centres between January 2009 and December 2012. In total, 347 patients were analysed; the median age was 63 years (range 23-90). The primary tumour was in the duodenum (60.6%), jejunum (20.7%) and ileum (18.7%). The prevalence of predisposing disease was 8.7%, 6.9%, 1.7%, 1.7% and 0.6% for Crohn disease, Lynch syndrome, familial adenomatous polyposis, celiac disease and Peutz-Jeghers syndrome, respectively. At diagnosis, 58.9%, 5.5% and 35.6% of patients had localised and resectable, locally advanced unresectable and metastatic disease, respectively. Crohn disease was significantly associated with younger age, poor differentiation and ileum location, whereas Lynch syndrome with younger age, poor differentiation, early stage and duodenum location. Adjuvant chemotherapy (oxaliplatin-based in 89.9%) was performed in 61.5% of patients with locally resected tumours. With a 54-months median follow-up, the 5-year overall survival (OS) was 87.9%, 78.2% and 55.5% in Stages I, II and III, respectively. The median OS of patients with Stage IV was 12.7 months. In patients with resected tumours, poor differentiation (p = 0.047) and T4 stage (p = 0.001) were associated with a higher risk of death. In conclusion, our study showed that the prognosis of advanced SBA remains poor. Tumour characteristics differed according to predisposing disease. In SBA-resected tumours, the prognostic factors for OS were grade and T stage.

Chemotherapy in Resected Neuroendocrine Carcinomas of the Digestive Tract: A National Study from the French Group of Endocrine Tumours.

BACKGROUND: Neuroendocrine carcinomas (NECs) of the digestive tract are rare and aggressive tumours. In localised disease the treatment is surgery. Based on expert consensus, international guidelines recommend the administration of adjuvant chemotherapy combining etoposide and platinum derivatives, justified by the high risk of metastatic relapse. However, no clinical study has proven the benefit of neoadjuvant or adjuvant chemotherapy. OBJECTIVES: We aimed to evaluate the effect of neoadjuvant +/- adjuvant and adjuvant therapy in this indication. METHODS: We performed a retrospective observational French study to evaluate overall survival (OS) and disease-free survival (DFS), prognostic factors for survival, and chemotherapy toxicity. RESULTS: Seventy-three patients had surgical resection of a localised digestive NEC between January 1, 2000 and December 31, 2016. The majority of patients presented colorectal (35%) tumours and the median Ki-67 value was 70%. Forty-three patients received chemotherapy, either perioperative (neoadjuvant +/- adjuvant) or adjuvant. The median OS and DFS for the whole population was 24 and 9 months, respectively. The median OS and DFS for patients receiving chemotherapy was 62 and 13 months, respectively. Positive postoperative node status and Ki-67 ≥80% had a negative prognostic impact on OS and DFS. Administration of chemotherapy had a positive prognostic impact on OS and DFS. Sixteen grade 3/4 toxicities were reported without toxic death. CONCLUSIONS: Our results suggest a positive effect on survival of chemotherapy in resected digestive NECs, but further studies are needed to confirm these results.

Comparison of three lymph node staging schemes for predicting the outcome in patients with small bowel adenocarcinoma: A population-based cohort and international multicentre cohort study.

BACKGROUND: The prognostic roles of three common lymph node staging schemes, number of positive lymph nodes (pN), lymph node ratio (LNR) and log odds of positive lymph nodes (LODDS) in small bowel adenocarcinoma (SBA) are unclear. We assessed their prognostic ability in SBA. METHODS: A total of 2128 patients diagnosed with SBA between 1988 and 2010 from the Surveillance, Epidemiology, and End Results (SEER) database and 186 patients from 15 hospitals in France and China were identified. We evaluated the prognostic ability of the schemes in both continuous and stratified patterns using R2, Harrell's C, and time-dependent receiver operating characteristic curve analyses. FINDINGS: For continuous pattern, the LODDS had a better capacity of discrimination and higher accuracy of prognosis than pN and LNR. Similarly, the stratified LODDS classification had a better performance of discrimination and higher accuracy of prognosis than the pN and LNR classification. The multivariable model using the LODDS classification also showed superiorly predictive accuracy and discriminatory capacity to those of the 7th and, 8th TNM node and LNR classification. These results were fully validated in an independent international multicentre cohort. INTERPRETATION: The LODDS scheme showed a better prognostic performance than the LNR or pN schemes in patients with SBA regardless of continuous or stratified pattern. The LODDS scheme could serve as an auxiliary to lymph node staging systems in future revisions of the American Joint Committee on Cancer (AJCC) manual. FUND: This work was funded by the Zhejiang Province Natural Science Fund of China.

Immunotherapy and metastatic colorectal cancers with microsatellite instability or mismatch repair deficiency.

Microsatellite instability (MSI) is a molecular indicator of defective DNA mismatch repair (dMMR) and is observed in approximately 5% of metastatic colorectal cancers (mCRC). MSI is a major predictive biomarker for the efficacy of immune checkpoint inhibitors (ICKi) amongst mCRC patients. After summarizing the literature about the efficacy of conventional cytotoxic regimens, we will highlight studies that have demonstrated the clinical activity of ICKi for patients with chemoresistant MSI/dMMR mCRC. Then we will focus on ongoing clinical trials and emerging challenges for the treatment of patients with MSI/dMMR mCRC.

Resection of small bowel adenocarcinoma metastases: Results of the ARCAD-NADEGE cohort study.

INTRODUCTION: Data are lacking with regard to curative resection of metastasis from small bowel adenocarcinoma (SBA). This study evaluated outcomes and prognostic factors in patients with curatively resected metastatic SBA. METHODS: A series of 34 patients undergoing resection of metastatic SBA from January 2009 to November 2014 at French centers were included into this cohort study. The primary endpoint was overall survival (OS). Secondary endpoints were recurrence-free survival (RFS) and prognostic factors. Univariate analyses were performed to determine prognostic risk factors. RESULTS: The sites of SBA metastases were peritoneal (29.4%), liver (26.5%), lymph nodes (11.8%), lung (2.9%), multiple (14.7%), and other (14.7%). Thirty (88.2%) patients received adjuvant or perioperative chemotherapy, mainly was oxaliplatin-based (76.5%). The median OS was 28.6 months and RFS was 18.7 months. Fourteen (41.2%) patients survived for more than 36 months. In univariate analysis, poor differentiation (P = 0.006), invaded margins (P = 0.003), and lymphatic invasion in the primary tumor (P = 0.039) were associated with decreased OS. CONCLUSION: Overall survival of patients after resection of metastatic SBA remains poor, but long-term survivors are observed. Resection of metastatic SBA should be consider if patients are expected to be operated on with curative intent and have moderately or well-differentiated tumors.

ERBB3-Activating Mutations in Small Bowel Adenocarcinomas.

PURPOSE: Functional studies have demonstrated that some mutations of ERBB3, which encodes for human epidermal growth factor receptor (HER) 3, are oncogenic via activation of the ErbB family signaling pathway. Significant clinical activity of anti-HER2 therapies (trastuzumab plus lapatinib combination or afatinib) has been reported in patients with ERBB3-mutated cancers. This study was designed to report the rate of activating ERBB3 mutations in small bowel adenocarcinoma (SBA), a rare tumor type in which we previously reported a high rate (12%) of ERBB2-activating mutations. MATERIALS AND METHODS: DNA from 74 SBAs, previously characterized for ERBB2 mutations and mismatch repair status, was submitted for sequencing of ERBB3 exons 3, 6, 7, 8, and 23. Orthogonal validation by targeted next-generation sequencing was performed. RESULTS: Four of 74 SBAs (5.4%) displayed ERBB3-activating mutations, including three p.V104M mutations (c.310 G>A) in exon 3 and one p.E928G mutation (c.2783 A>G) in exon 23. No mutations were detected in exons 6, 7, and 8. ERBB3-activating mutations were associated with microsatellite instability (P = .002) and the presence of ERBB2-activating mutations (P = .002). Two SBAs with co-occurrence of ERBB2 and ERBB3 mutations were further analyzed by targeted next-generation sequencing. Mutant allelic frequencies suggested that both mutations were shared by the same clone rather than being harbored by mutually exclusive tumor subclones. CONCLUSION: SBAs display a high rate of ERBB3-activating mutations, which have been shown to be targetable by anti-HER2 therapies. Strikingly, ERBB3 was frequently comutated with ERBB2, suggesting a strong oncogenic addiction of these SBAs to the HER2 pathway.

Small bowel adenocarcinoma: French intergroup clinical practice guidelines for diagnosis, treatments and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO).

BACKGROUND: This document is a summary of the French intergroup guidelines regarding the management of small bowel adenocarcinoma published in October 2016. METHOD: This collaborative work, co-directed by most French Medical Societies, summarizes clinical practice recommendations (guidelines) on the management of small bowel adenocarcinoma. Given the lack of specific data in the literature, all references are given by analogy with colon cancer. The classification used is the AJCC (American Joint Committee on Cancer) pTNM classification (7th edition 2009). RESULTS: Small bowel adenocarcinoma has a poor prognosis; less than 30% of patients survive for 5 years after the (first) diagnosis (5-year survival of less than 30%). Due to the rarity of the disease and the retrospective data, most recommendations are based on expert agreement. The initial evaluation is based on chest-abdomen-pelvis CT scan, CEA assay, GI endoscopy and colonoscopy in order detect lesions associated with a predisposing disease. Surgical treatment is currently the only curative option for stage I and II. Adjuvant chemotherapy can be discussed for Stage III and Stage II with T4 (expert agreement). With regard to metastatic tumors, treatment with fluoropyrimidine combined with platinum salts should be considered (expert agreement). CONCLUSION: Few specific data exist in the literature on this type of tumor; most of the recommendations come from expert agreements or by analogy with colon cancer. Thus, each case must be discussed within a multidisciplinary team.

Immunotherapy and patients treated for cancer with microsatellite instability.

Microsatellite instability (MSI) is a tumor phenotype linked to somatic or germline (Lynch syndrome) inactivating alterations of DNA mismatch repair genes. A broad spectrum of neoplasms exhibits MSI phenotype, mainly colorectal cancer, endometrial cancer, and gastric cancer. MSI tumors are characterized by dense immune infiltration and high load of tumor neo-antigens. Growing evidence is accumulating on the efficacy of immune checkpoint inhibition for patients treated for MSI solid tumors. We present a comprehensive overview of MSI phenotype, its biological landscape and current diagnostic methods. Then we focus on MSI as a predictive biomarker of response to immune checkpoint inhibition in the context of colorectal cancer and non-colorectal tumors.

Perioperative chemotherapy with FOLFOX in resectable gastroesophageal adenocarcinoma in real life practice: An AGEO multicenter retrospective study.

PURPOSE: Perioperative chemotherapy with 5-fluorouracil and cisplatin, with or without epirubicin, improves overall survival in resectable gastroesophageal junction and gastric adenocarcinoma. The aim of this retrospective multicenter study was to evaluate the safety and efficacy of perioperative chemotherapy with a FOLFOX-based regimen. PATIENTS AND METHODS: We enrolled patients with resectable gastric or gastroesophageal adenocarcinoma, who had at least 3 cycles of a pre-operative FOLFOX-based regimen. The primary end point was the feasibility of the peri-operative chemotherapy. RESULTS: We enrolled 109 patients from 2007 to 2012 in 12 centres. Their median age was 66, 67% were men and 73% had gastric tumours. The median number of chemotherapy courses was 6 with a median of 4 pre-operative cycles and 2 post-operative cycles. Twenty-three patients received at least 8 cycles of chemotherapy. In univariate analysis, the Karnofsky index at inclusion was the only factor associated with 8 cycles of chemotherapy. An R0 resection was achieved in 100 patients (95.2%). CONCLUSION: The FOLFOX-based perioperative regimen achieves favourable results in real life practice. The optimal number of chemotherapy cycle remains to be determined. FOLFOX regimen may be used as an alternative treatment option to a cisplatin-based regimen in resectable gastroesophageal adenocarcinoma. A prospective randomized trial is needed to confirm these results.