INTRODUCTION: When initial resection of rectal neuroendocrine tumors (r-NETs) is not R0, persistence of local residue could lead to disease recurrence. This study aimed to evaluate the interest of systematic resection of non-R0 r-NET scars. METHODS: Retrospective analysis of all the consecutive endoscopic revisions and resections of the scar after non-R0 resections of r-NETs. RESULTS: A total of 100 patients were included. Salvage endoscopic procedure using endoscopic submucosal dissection or endoscopic full-thickness resection showed an R0 rate of near 100%. Residual r-NET was found in 43% of cases. DISCUSSION: In case of non-R0 resected r-NET, systematic scar resection by endoscopic full-thickness resection or endoscopic submucosal dissection seems necessary.

BACKGROUND:Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of death by cancer worldwide. Mostly diagnosed with locally advanced or metastatic disease, patients lack treatment options. Gene alterations (GAs) are frequently observed in PDAC, some of which are considered for molecular targeted therapies (MTTs), with potential clinical benefits and improved outcomes. However, the applicability of molecular profiling (MP) for precision medicine in PDAC remains to be demonstrated.METHODS:We conducted a retrospective analysis of all patients, aged ≥18 years with histologically confirmed PDAC, who underwent tumor MP between 2010 and 2020 in our institution as part of personalized medicine trials. The primary study endpoint was overall survival (OS), and (minimal follow-up was 6 months after MP).RESULTS:Of 115 eligible patients, MP was successful in 102 patients (89%). KRAS mutations were the most frequent GAs, mostly G12D. Based on ESCAT classification, actionable GAs were found in 29 patients (28%), involving mainly BRCA1 or BRCA2 (5 (18%)), HER2 (5 (18%)), MTAP (5 (18%)), and FGFR (3 (11%)). Only 12 of these 29 patients (41%, or 10% of the whole population) received MTTs, with a median progression-free survival of 1.6 months. Median OS was 19 months in patients with actionable GAs treated with MTTs (n = 12 (11.8%)), 14 months in patients with actionable GAs treated with standard therapies (n = 17 (16.7%)), and 17 months in patients without actionable GAs treated with standard therapies (n = 73 (71.5%); p = 0.26). The absence of liver metastases was associated with better OS (HR = 0.471, p = 0.01). The highest OS following MTT was observed in patients with BRCA mutations treated with olaparib.INTERPRETATION:Actionable GAs were found in more than a quarter of patients with advanced PDAC. Overall, targeting actionable GAs with MTTs was not associated with improved OS in this retrospective study with limited patient numbers. However, selected GA/MTT combinations (e.g., BRCA mutations/olaparib) were associated with a better outcome.

"Juvenile-like (hyperplastic/inflammatory) mucosal polyp" is a term proposed for rare benign mesenchymal lesions of the gastro-intestinal tract so far reported only in patients with type 1 neurofibromatosis (NF1). We report here a first sporadic case of NF1-associated mucosal inflammatory polyp of the colon. The diagnosis was made in a 53-year old female patient with a large polypoid tumor of the cecum. The lesion was predominantly mucosal, made of fibroblast-like cells associated with inflammatory infiltrates rich in eosinophils and containing entrapped, distorted epithelial glands, responsible for the juvenile-like appearance. Whole exome sequencing showed a pathogenic variant of NF1. The patient had no evidence of NF1; no NF1 mutation was detected in normal tissues. Our observation may support the existence of juvenile-like inflammatory polyps associated with NF1 alterations, either germline or somatic. This justifies to test NF1 in difficult-to-classify gastrointestinal mesenchymal tumors.

605 Background: Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of death by cancer worldwide. Mostly diagnosed with locally advanced or metastatic disease, patients lack for treatment options. Gene alterations (GAs) are frequently observed in PDAC, some of them considered as actionable with molecular targeted therapies (MTTs), with potential clinical benefits and improved outcomes. Methods: We conducted a retrospective analysis of all patients, aged ≥18 years, with histologically confirmed PDAC, who underwent tumor molecular profiling between 2010 and 2020 in our institution as part of personalized medicine trials. Overall survival was the primary study endpoint (minimal follow-up after molecular profiling, 6 months). Results: Of 115 eligible patients, molecular profiling was successful in 102 patients (89%). KRAS mutations were the most frequent GAs, mostly G12D. Actionable GAs were found in 29 patients (28%), involving mainly BRCA1/2 (5 [18%]), HER2 (5 [18%]), MTAP (5 [18%]), and FGFR (3 [11%]). Only 12 of these 29 patients (41%, or 10% of the whole population) could receive MTTs accordingly, with a median progression-free survival of 1.6 months. Median OS was 17 months in patients with actionable GAs treated with MTTs (n = 12 [11.8%]), 14 months in patients with actionable GAs not treated with MTTs (n = 17 [16.7%]), and 19 months in patients without actionable GAs treated with standard therapies (n = 73 [71.5%]; p = 0.26). The absence of liver metastases was associated with better OS (HR = 0.471, p = 0.01). The longest duration of response with MTTs was observed in patients with BRCA mutations treated with olaparib. Conclusions: Actionable GAs are found in more than the quarter of patients with advanced PDAC. Overall, targeting actionable GAs with MTTs was not associated with improved OS in this retrospective study. However, selected GA/MTT duets (e.g., BRCA mutations/olaparib) were associated with better outcome.

Purpose To examine clinical outcomes and quality of life of patients with anal squamous cell carcinoma treated with interstitial pulsed-dose-rate brachytherapy (PDR-BT) with a boost to residual tumor after external radiotherapy. Material and methods Medical records of patients receiving a brachytherapy boost after radiotherapy for anal squamous cell carcinoma in our Institute between 2008 and 2019 were retrospectively reviewed. After receiving pelvic irradiation ± concurrent chemotherapy, patients received PDR-BT boost to residual tumor, in order to deliver a minimal total dose of 60 Gy. Patients’ outcomes were analyzed, with primary focus on local control, sphincter preservation, morbidity, and quality of life. Results A total of 42 patients were identified, included 24, 13, and 5 patients with I, II, and III tumor stages, respectively. Median brachytherapy (BT) dose was 20 Gy (range, 10-30 Gy). Median dose per pulse was 42 cGy (range, 37.5-50 cGy). With median follow-up of 60.4 months (range, 5.4-127.4 months), estimated local control and colostomy-free survival rates at 5 years were both 88.7% (95% CI: 67.4-96.4%). The largest axis of residual lesion after external beam radiation therapy (EBRT) and poor tumor shrinkage were associated with more frequent relapses (p = 0.02 and p = 0.007, respectively). Out of 40 patients with more than 6 months follow-up, only one experienced severe delayed toxicity (fecal incontinence). Health quality perception was very good or good in 20 of 22 (91%) patients, according to their replies of quality-of-life surveys. A total dose ≥ 63 Gy was associated with higher number of anorectal grade 1+ toxicities (n = 1.5 vs. n = 0.61, p = 0.02). Conclusions In this cohort of 42 patients with mainly I and II tumor stages, PDR-BT boost allowed for local control in 88.7% of patients, with only one grade 3 anorectal toxicity.

Background Liver metastases are mainly supplied by the hepatic artery, allowing the administration of intra-arterial hepatic chemotherapy (IAHC) while preserving normal parenchyma. The progression-free survival and response rate are prolonged by IAHC which can improve the rate of secondary resectability. Severe abdominal pain requiring high-dose opioids can appear during HIAC administration. This pain is related to extrahepatic infusion and gastroduodenal ulceration. However, intense abdominal pain was observed under oxaliplatin IAHC specifically without any extrahepatic infusion. Method We retrospectively reviewed the charts of 68 patients who received IAHC in our center between 2011 and 2015. Patient's demographics and disease characteristics were collected. Other variables such as the type, duration, and dosage of the chemotherapy administered, as well as the usage of painkillers before, during, or after intra-arterial administration, were also registered. Results The mean age of the patients was 59 years. 61.7% were male (n = 42). The mean dose of oxaliplatin administered was 162 mg per cure over 6.7-h course. Fifty percent were diagnosed with a left colon cancer, and 85.2% had synchronous liver metastasis. While 47% of patients received IAHC as a third-line therapy, the main chemotherapeutic drug was oxaliplatin (85.2% of cases; n = 58), then OPTILIV protocol (5FU, irinotecan, oxaliplatin) (13.3%; n = 9), and mitomycin C (1.5%; n = 1). A dose reduction of 23.6% had been noted in 58.8% (n = 40) cases due to adverse effects. Among patients who received opioids during IAHC (n = 40), 20% required opioids in intercure. Before, during, and after IAHC administration, patients complained of abdominal pain in 8.8%, 58.8%, and 19.1%, and opioids were used in 10.2%, 57.3%, and 19.1%, respectively. The main onset of pain occurs during the third cycle of chemotherapy. Among our patients, 11.7% and 22% had ulcer and extrahepatic perfusion, respectively, while 7.3% of them were asymptomatic. The mean occurrence of these signs was during the fourth cycle of IAHC. 33.8% and 52.9% of patients had abdominal pain while an extended and short infusion time, respectively. Conclusion Lengthening of the infusion time did not prevent the occurrence of abdominal pain significantly but was nonetheless decreased compared with patients undergoing short infusion durations. Pain was more common in patients who did not have a dose reduction and who presented with ulcer and extrahepatic perfusion. Abdominal pain occurred on average one cycle before ulcer or extrahepatic perfusion diagnosis. In current practice, pain should be an alarming indicator in patients receiving IAHC, as it may be associated with ulcer or extrahepatic perfusion and thus requiring opioids.

Aims Endocuff vision (ECV) is the second generation of a recent device designed to improve polyp detection. The aim of this study was to evaluate the impact of ECV on adenoma detection rate (ADR) in routine colonoscopy.

Introduction: Peritoneal metastases from neuroendocrine tumors are associated with a bad prognosis. The objective of our study was to evaluate whether surgical resection could lead to prolonged survival in selected patients. This survival was compared to that of patients operated for liver metastasis. Methods: From our prospectively maintained database we included 88 patients who underwent the complete resection of peritoneal and/or liver metastasis between January 1995 and December 2016 in Gustave-Roussy. Three resection groups were compared: peritoneal metastasis alone, liver metastasis alone, and the combined resection of liver and peritoneal metastases. Results: The median peritoneal cancer index was 10 in the peritoneal group and 11 in the peritoneal + liver group. The 5-year overall survival was 81% (60-100) in the peritoneal group compared to 78% (65.2-92.8) in the liver group, and 72% (58.7-89.7) in the peritoneal + liver group (p = 0.71). The 3-year disease-free survival reached 26.9% (16.1-45.1) in the liver group, 12.5% (2.3-68.2) in the peritoneal group, and 32.4% (19.9-52.6) in the combined liver + peritoneal group (p = 0.45). In the univariate analysis, the prognosis factors for a longer survival were: small bowel primary tumor origin, low preoperative chromogranin A level, and tumor grade <= 1. Conclusion: Despite a high recurrence rate, long-term overall survival can be achieved after the resection of peritoneal metastasis in selected patients. This survival is comparable to that of patients operated for liver metastasis only. Surgery should stand as a standard treatment for peritoneal metastases in patients with resectable disease.

Objective Endocuff Vision (ECV) is the second generation of a device designed to improve polyp detection. The aim of this study was to evaluate its impact on adenoma detection rate (ADR) in routine colonoscopy. Design This cluster-randomised crossover trial compared Endocuff-assisted (ECV+) with standard (ECV-) colonoscopy. Two teams of 11 endoscopists each with prior ECV experience, balanced in terms of basal ADR, gender and case volume were compared. In randomised fashion, the teams started with ECV+ or ECV- and switched group after inclusion of half of the cases. The main outcome criterion was ADR difference between ECV+ and ECV-. Subgroup analysis was done for physicians with low and high ADR (< or ≥ 25%). Results During two periods of 20 and 21 weeks, respectively, the 22 endoscopists included 2058 patients (1032 ECV- vs 1026 ECV+, both groups being comparable). Overall ADR for both groups taken together was higher with ECV (39.2%) than without (29.4%; p<0.001) irrespective of the sequence of use (ECV+ or ECV- first), but mostly in adenomas <1 cm. In the physician subgroup analysis, only high detectors showed a significant ADR increase (from 31% to 41%, p<0.001), while the increase in the low detectors was not significant (from 24% to 30%, p=0.11). ECV had a positive impact in all colonic locations, except for the rectum. No ECV- related complication was reported. Conclusion We observed a significant ADR difference of approximately 10% by the use of ECV. By subgroup analysis, this increase was significant only in physicians classified as high detectors. Trial registration number ClinicalTrials.gov ( NCT03344055 ).

552 Background: Biliary tract cancers (BTC) are rare and heterogeneous cancers with poor prognosis. Several actionable genomic targets have been described in BTC but data on the efficacy of targeted therapies remain limited. The main objectives of this retrospective study was to evaluate the frequency of actionable genomic alterations among BTC and the impact of targeted therapy. Methods: We performed a retrospective analysis on BTC patients seen at Gustave Roussy (IGR) from Dec 2011 to Jul 2019. All clinical and genomic reports were reviewed. Results: The study population included 212 patients with the main following characteristics: median age 61 years, female 51%, intrahepatic cholangiocarcinoma 57%, median of 2 previous lines. Of 212 BTC patients, 170 patients had a genomic profile based on archival tissue or a new tumor biopsy (IGR panel n = 120; Foundation One panel n = 92 ). 124 patients (73%) had at least one genomic alteration and 68 (40%) patients had genomic alteration considered as actionable. The most common actionable targets were FGFR2 rearrangement/mutation (n = 24, 35.3%), HER2/3 mutations (n = 9, 13.2%) and IDH1/2 mutations (n = 7, 10.3%). Of those 68 patients, 58 received the matched targeted therapy: FGFR inhibitor n = 24, HER2/3 inhibitors n = 9, Akt/PIK3CA/mTOR inhibitors n = 7, IDH1 inhibitor n = 6. In the treated population, the objective response rate was 36.2% and the disease control rate 85.1%. Progression-free survival (PFS) was 6.2 months compared to 2.8 months (p = 0.02) for patients who did not received targeted treatment. Overall survival (OS) was 17.7 months compared to 11.0 months (p = 0.03) for patients who did not received targeted treatment. Conclusions: Actionable genomic targets are frequent among BTC. Profiling-directed therapies resulted in a 36% response rate, a 85% tumor control rate and a 6.2 months PFS which compare favorably to second-line chemotherapy. A randomized trial is required to confirm the benefit of precision medicine in BTC.

Malignant dysphagia is the most common symptom in advanced oesogastric cancers patients. Relief of dysphagia allows quality of life improvement, nutritional replenishment and potentially improves prognosis. Chemotherapy alone is effective and should be prioritised in patients with metastatic disease a good performance status, and its impact on dysphagia should be determined before further interventions are planned. Regarding local treatments, the insertion of a covered self-expandable metallic stent is the most commonly used alternative, as it allows for the rapid relief of severe dysphagia. Although several randomised trials have highlighted the role of oesophageal brachytherapy, this technique is often not easily accessible. Contemporary trials are ongoing to better define the role of external radiation therapy. While awaiting these results, external radiation therapy can be considered as a second-best option for patients with a life-expectancy > 3 months. It is important to offer nutritional support and to integrate quality of life measures in the palliative management of dysphagia. This multidisciplinary international position paper aims to propose a decision-making process and highlight randomised trials for the management of malignant dysphagia in metastatic oesogastric cancer patients.

PURPOSE:Esophageal cancer is characterized by its propension to local evolution, which conditions prognosis and quality of life. Brachytherapy may be a therapeutic option for all stages of esophageal cancer. METHODS AND MATERIALS:This retrospective unicentric study included all consecutive patients treated for an esophageal high-dose-rate brachytherapy in our institution from 1992 to 2018. RESULTS:Ninety patients were included. They were treated in four distinct indications: exclusive (7 patients), boost after external beam radiotherapy (41), reirradiation (36), or palliative aim (6). Most frequently prescribed schemes were 3 × 5 Gy (boost) or 6 × 5 Gy (exclusive treatment and reirradiation) at applicator's surface or at 5 mm. At the end of follow-up, 50% of patients had presented with local recurrence. Seventeen percent of patients had a metastatic relapse. Median overall survival was 15 months in the whole cohort: 22 months in the boost setting, 25 months for exclusive brachytherapy, 15 months for reirradiation, and only 2 months for palliative treatment. Tumor length at brachytherapy, brachytherapy dose, and interfraction response were significantly associated to overall survival. 40% of patients presented with grade 2+ toxicity, mostly esophagitis, including three toxic deaths. CONCLUSIONS:Although local control outcomes are still poor, one must remember that patients are unfit for any curative therapeutic option and that palliative chemotherapy offers mediocre results. The most promising setting probably is reirradiation because brachytherapy offers a remarkable dose gradient allowing best organ at risk sparing, with an encouraging rate of long survivors (19% at 2 years). Esophageal brachytherapy deserves to be further investigated because some patients, even unfit, may benefit from it, with acceptable toxicity.

BACKGROUND:Adenoma detection rate (ADR) is correlated with the risk of interval colorectal cancer and is considered as a quality benchmark for colonoscopy. Serrated polyp detection rate (SPDR) might be a more stringent indicator of quality in polyp detection.AIMS:To evaluate in a 2-year monocentric observational study patient-dependent and endoscopist-dependent factors influencing ADR and SPDR in daily practice.METHODS:We determined ADR and SPDR. We collected patient-dependent factors and endoscopist-dependent factors. Links between these data and detection rates were assessed by uni- and multivariate analysis.RESULTS:A total of 11682 colonoscopies were performed (female: 54.3%; male: 45.7%; median age 58) by 30 endoscopists (female: 9; male: 21). ADR and SPDR were 29.2% and 8%, respectively. In multivariate analysis, ADR was associated with patient-dependent factors: age (OR 1.044, CI 95% 1.040-1.048), male gender (OR 1.7, CI 95% 1.56-1.85), personal history of polyp/cancer (OR 1.53, CI 95% 1.3-1.9), and positive fecal immunochemical test (OR 2.47, CI 95% 2.0-3.1). In multivariate analysis, SPDR was associated with withdrawal time (OR 1.25, CI 95% 1.17-1.32), low volume activity (OR 1.3, CI 95% 1.1-1.52), and personal history of polyp/cancer (OR 1.61, CI 95% 1.15-2.25).CONCLUSION:In this large series of routine colonoscopies, we found that ADR was mainly driven by patient-dependent conditions, i.e., age, male gender, colonoscopy indication for positive FIT, and a personal history of polyp or cancer. In contrast, SPDR was mainly related to endoscopist-dependent factor, i.e., withdrawal time and low volume activity.

Background: Cancer survivors have a 14% increased risk of developing a malignancy compared with the general population. Second radiation-induced malignancies with different histologies have been described in different organs. Based on individual observations, we hypothesized that neuroendocrine carcinoma (NEC) could arise in irradiated organs. Methods: In a retrospective analysis of Gustave Roussy database of NEC patients (small cell lung cancer excluded) diagnosed as a second cancer, we looked for the frequency of grade 3 NEC that arose in patients who had received previous radiation therapy for a first cancer. Radiation therapy for the first cancer, dose, location of radiation therapy, pathological characteristics, overall survival, and response to treatment of secondary NEC were analyzed. Results: From January 1995 to December 2017, 847 cases of NEC were seen at Gustave Roussy. Among them, 95 (11.2%) patients had a history of previous malignancy of which 36 (4%) had been treated with radiation therapy. Out of these 36 patients, 12 (1.4% of all NEC patients) developed a NEC within the previous irradiated organ (median dose of 50 Gy, range 36–67.5). Most frequent first cancers were breast cancer (n = 4) and Hodgkin lymphoma (n = 3). NEC arose within a median time of 21.7 years (range 5.1–36.4) from radiation in the thorax (n = 5), digestive tract (n = 3), and other sites. Five large cell NEC, 3 small cell NEC, 1 mixed neuroendocrine neoplasm and 3 not otherwise specified NEC were diagnosed. Ten patients had stage IV disease at diagnosis; median overall survival was 37.8 months (95% CI [17.6 to NA]). Three patients (25%) achieved complete response with multimodal treatment. Conclusions: NEC can arise from previously irradiated organs and may have a better outcome in this setting. Other risk factors should be investigated to explain the high rate of previous cancer in this population of neuroendocrine neoplasm.

Stereotactic radiotherapy of pancreatic tumors needs implantation of fiducial markers to help targetting the tumor. In this retrospective study, we share our experience with pancreatic fiducial EUS guided placement. We looked into its technical feasibility, innocuity and strategies for optimal fiducial distribution. From 2014 to 2017, 27 patients (22 with pancreatic adenocarcinoma and 5 with metastasis to the pancreas) underwent EUS pancreatic fiducial placement in our center. The same operator used a standard linear echoendoscope and a dedicated 22G EUS needle with 4 preloaded fiducials. Depending on radiotherapy equipment availability at the time of the treatment, 19 patients underwent conventional radiotherapy and 8 patients stereotactic radiotherapy. We retrospectively evaluated the number of markers delivered, their position, migration and adverse events. For patients being treated by stereotactic radiotherapy, the radiotherapy team evaluated markers tracking success by the radiotherapy device and positioning compared to the ideal fiducial geometry (defined as a distance of > 2 cm and < 7 cm, an angle greater than 15° and no collinearity between each markers). For a stereotactic treatment to be possible, at least 2 markers where to be tracked at all times during treatment and ideally 3 in order to restrict as much as possible the irradiated field. Misplacement or immediate fiducial migration was noticed for 3 of the first 9 patients treated. Immediate marker placement was satisfactory in the last 18 patients. The radiotherapy device managed to track at least 2 markers in 7 out of the 8 patients who underwent stereotactic radiotherapy even though ideal fiducial geometry was never achieved. All patients had at least 2 markers less than 2 cm apart. No serious adverse event was noted. One patient reported abdominal pain for 48h after the procedure but pancreatic enzymes level remained normal. A few technical difficulties arose during the first fiducial placements. In one patient, the endoscope operating channel was punctured and needed repair. In another patient, the delivery kit needle was kinked by the endoscope elevator and we needed to use another one. Intrapancreatic fiducial placement can be achieved safely by means of EUS but, due to a learning curve, the delivery technique should be attempted by experienced endosonographers. Furthermore, fiducial geometry allowing efficient tracking is not simple and one should seek feedback from the radiotherapy team. Fluoroscopic guidance combined with EUS seems to facilitate placement. As soon as fiducial placement quality will allow optimal tracking, it will be possible to conduct a prospective study evaluating stereotactic radiotherapy in pancreatic tumor treatment. Fiducial tracking by the stereotactic radiotherapy device None

Le taux de détection des adénomes (TDA) est corrélé au risque de cancer d'intervalle et est un marqueur de qualité reconnu de la coloscopie. Plus récemment, il a été suggéré que le taux de détection des adénomes festonnés (TDAF) pourrait être un marqueur plus fin de la qualité en endoscopie (Anderson et al., 2017). Nous avons prospectivement évalué ces taux en coloscopie de routine sur une période de 2 ans.