Risk factors for EUS-guided radiofrequency ablation adverse events in patients with pancreatic neoplasms: a large national French study (RAFPAN study).

BACKGROUND AND AIMS: EUS-guided radiofrequency ablation (EUS-RFA) has been described as a potentially curative option for solid and cystic pancreatic neoplasms. We aimed to assess the safety and efficacy of pancreatic EUS-RFA in a large study population. METHODS: A retrospective study retrieving all consecutive patients who underwent pancreatic EUS-RFA during 2019 and 2020 in France was conducted. Indication, procedural characteristics, early and late adverse events (AEs), and clinical outcomes were recorded. Risk factors for AEs and factors related to complete tumor ablation were assessed on univariate and multivariate analyses. RESULTS: One hundred patients (54% men, 64.8 ± 17.6 years old) affected by 104 neoplasms were included. Sixty-four neoplasms were neuroendocrine neoplasms (NENs), 23 were metastases, and 10 were intraductal papillary mucinous neoplasms with mural nodules. No procedure-related mortality was observed, and 22 AEs were reported. Proximity of pancreatic neoplasms (≤1 mm) to the main pancreatic duct was the only independent risk factor for AEs (odds ratio [OR), 4.10; 95% confidence interval [CI), 1.02-15.22; P = .04). Fifty-nine patients (60.2%) achieved a complete tumor response, 31 (31.6%) a partial response, and 9 (9.2%) achieved no response. On multivariate analysis, NENs (OR, 7.95; 95% CI, 1.66-51.79; P < .001) and neoplasm size <20 mm (OR, 5.26; 95% CI, 2.17-14.29; P < .001) were independently related to complete tumor ablation. CONCLUSIONS: The results of this large study confirm an overall acceptable safety profile for pancreatic EUS-RFA. Close proximity (≤1 mm) to the main pancreatic duct represents an independent risk factor for AEs. Good clinical outcomes in terms of tumor ablation were observed, especially for small NENs.

The safety and efficacy of a new 20-mm lumen apposing metal stent (lams) for the endoscopic treatment of pancreatic and peripancreatic fluid collections: a large international, multicenter study.

BACKGROUND: Lumen apposing metal stent (LAMS) allows an easy access to peripancreatic fluid collections (PPFCs) and the possibility of performing direct endoscopic necrosectomy (DEN). The aim of our study was to evaluate the safety and efficacy of a new 20-mm LAMS in the management of PPFCs. This novel stent represents the largest diameter LAMS available on the market to date. METHODS: This is an international, multicenter retrospective study involving 20 centers. Consecutive patients who underwent EUS-guided PPFC drainage using a 20-mm LAMS were included. Primary outcomes were technical and clinical success. Secondary outcomes were rate and the severity of adverse events. RESULTS: A total 105 patients underwent PPFC drainage using the new 20-mm LAMS and 106 LAMS were placed. Technical success was 100% (106/106). 7/105 patients died due to causes not related to the stent. Clinical success was achieved in 92/98 patients (93.9%). Significant adverse events occurred in 8/98 patients (8.16%): 4 cases (4.08%) of bleeding, 3 cases (3.06%) of suprainfection, 1 case of gastric outlet obstruction. CONCLUSIONS: This multicenter study demonstrated acceptable rates of technical and clinical success using a new 20-mm LAMS for PPFC, including walled-off pancreatic necrosis (WOPN). The results of our study suggest that a new 20-mm LAMS is non-inferior in terms of safety, efficacy, and adverse events as compared to smaller diameter LAMS in the management of PPFCs, including pancreatic psuedocysts (PP) and WOPN. Randomized controlled studies will be needed to determine the ideal size of LAMS need to achieve the greatest clinical benefit with the minimized risk exposure for this high-risk patient population.

Safety of Endoscopic Ultrasound-Guided Fine-Needle Aspiration for Pancreatic Solid Pseudopapillary Neoplasm Before Surgical Resection: A European Multicenter Registry-Based Study on 149 Patients.

OBJECTIVES: The results of only a few endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for pancreatic solid pseudopapillary neoplasm (SPN) have been published, and the safety of the procedure has never been investigated. Our study compared the recurrence rate in patients with and without preoperative EUS-FNA. METHODS: This European multicenter registry-based study was conducted in 22 digestive units, and retrospectively included all patients who underwent complete resection of a pancreatic SPN from 2000 to 2018. Patients with and without initial EUS-FNA were compared, and postsurgery recurrence and the associated risk factors were evaluated. RESULTS: A complete resection of a pancreatic SPN was performed in 149 patients (133 women, 89%), with a mean age of 34 (standard deviation, 14) years. There were no significant differences between the with (78 patients) and without (71 patients) EUS-FNA groups, except for age and tumor size and location.Preoperative EUS-FNA allowed pancreatic SPN diagnosis in 63/78 cases (81%). After a mean follow-up of 43 (standard deviation, 36) months, recurrence was noted in 4 patients (2.7%). Preoperative EUS-FNA was not correlated with recurrence, but an older age (P = 0.005) was significant. CONCLUSIONS: Preoperative EUS-FNA does not affect pancreatic SPN recurrence. In this series, old age was significantly correlated with recurrence.

International multicenter comprehensive analysis of adverse events associated with lumen-apposing metal stent placement for pancreatic fluid collection drainage.

BACKGROUND AND AIMS: High rates of technical and clinical success were reported for lumen-apposing metal stent (LAMS) placement for peripancreatic fluid collection (PFC) drainage. However, data on the adverse event (AE) rates are heterogeneous. The aim of this study was to evaluate the incidence, severity, management, and risk factors of AEs related to the use of LAMSs for drainage of PFCs in a large cohort of patients. METHODS: This is a multicenter, international, retrospective review from 15 centers of all patients who underwent placement of LAMSs for the management of PFCs. A nested case-control study was conducted in patients with (case) or without (control) AEs. RESULTS: Three hundred thirty-three procedures in 328 patients were performed (5 patients treated with 2 LAMSs). Technical success was achieved in 321 patients (97.9%). Three hundred four patients were finally included in the study (7 excluded for lost to follow-up information; 10 excluded for deaths unrelated to LAMSs). The rate of clinical success was 89.5%. Seventy-nine LAMS-related AEs occurred in 74 of 304 patients (24.3%), after a mean time of 25.3 days (median, 18 days; interquartile range, 6-30) classified as 20 (25.3%) mild, 54 (68.4%) moderate, or 5 (6.3%) severe. On multivariable analysis compared with control subjects, cases were more likely to have walled-off necrosis (WON) versus pancreatic pseudocysts (odds ratio, 2.18; 95% confidence interval, 1.09-4.46; P = .028), whereas cases were less likely to have undergone tract (balloon) dilation (yes vs no; odds ratio, .47; 95% confidence interval, .22-.93; P = .034). CONCLUSIONS: Data from this large international retrospective study confirm that the use of LAMSs for management of PFCs has excellent technical and good clinical success rates. The rate of AEs, however, is not negligible and should be carefully considered before using these stents for drainage of PFCs and in particular for WON. Further prospective studies are needed to confirm these findings. (Clinical trial registration number: NCT03544008.).

Impact of peroral cholangioscopy on the management of indeterminate biliary conditions: a multicentre prospective trial.

BACKGROUND AND AIMS: Single-operator cholangioscopy (SOC) can help diagnose biliopancreatic conditions. The impact of SOC on patient outcome has never been specifically addressed. PATIENTS AND METHODS: Consecutive patients bearing indeterminate biliary strictures (IDBS), or primary sclerosing cholangitis (PSC) with suspected cholangiocarcinoma, were included. Patients with IDBS had at least one previous inconclusive endoscopic retrograde cholangio pancreatography (ERCP) + cytology. Primary endpoint was the difference in adequacy of management planned before and after SOC with regard to final diagnosis obtained after surgery or 24 months follow-up. DESIGN: Prospective open-label multicentre trial. RESULTS: 61 patients were included (IDBS: 48; PSC: 13); 70.5% had a benign lesion (IDBS 66.7%, PSC 84.6%). The management adequacy rate was significantly higher after SOC than before SOC overall (p<10-5), in IDBS (p<0.001) and PSC (p<0.05) patients. SOC induced changes in the management of the majority of patients in all groups (60.3%). The overall sensitivity of combined visual impression and biopsy ranged from 52% to 63.6% depending on investigator or independent expert rating (κ 0.92-0.96), whereas specificity, positive and negative predictive values of SOC were, respectively, 100%, 100% and 83.6%. Patient management observed at the end of follow-up was consistent with that anticipated after SOC in 88.5% overall. CONCLUSION: Despite a moderate sensitivity for the diagnosis of malignancy, SOC has a dramatic impact on the management of patients with IDBS and PSC with suspected carcinoma. Cholangioscopy might be implemented in the workup of selected patients with challenging diagnosis, when a significant impact on outcome (essentially resection vs conservative management) is to be expected.

Complete endoscopic sphincterotomy with vs. without large-balloon dilation for the removal of large bile duct stones: randomized multicenter study.

Background and study aims Endoscopic sphincterotomy plus large-balloon dilation (ES-LBD) has been reported as an alternative to endoscopic sphincterotomy for the removal of bile duct stones. This multicenter study compared complete endoscopic sphincterotomy with vs. without large-balloon dilation for the removal of large bile duct stones. This is the first randomized multicenter study to evaluate these procedures in patients with exclusively large common bile duct (CBD) stones. Methods Between 2010 and 2015, 150 patients with one or more common bile duct stones ≥ 13 mm were randomized to two groups: 73 without balloon dilation (conventional group), 77 with balloon dilation (ES-LBD group). Mechanical lithotripsy was subsequently performed only if the stones were too large for removal through the papilla. Endoscopic sphincterotomy was complete in both groups. Patients could switch to ES-LBD if the conventional procedure failed. Results There was no between-group difference in number and size of stones. CBD stone clearance was achieved in 74.0 % of patients in the conventional group and 96.1 % of patients in the ES-LBD group (P < 0.001). Mechanical lithotripsy was needed significantly more often in the conventional group (35.6 % vs. 3.9 %; P < 0.001). There was no difference in terms of morbidity (9.3 % in the conventional group vs. 8.1 % in the ES-LBD group; P = 0.82). The cost and procedure time were not significantly different between the groups overall, but became significantly higher for patients in the conventional group who underwent mechanical lithotripsy. The conventional procedure failed in 19 patients, 15 of whom underwent a rescue ES-LBD procedure that successfully cleared all stones. Conclusions Complete endoscopic sphincterotomy with large-balloon dilation for the removal of large CBD stones has similar safety but superior efficiency to conventional treatment, and should be considered as the first-line step in the treatment of large bile duct stones and in rescue treatment.Trial registered at ClinicalTrials.gov (NCT02592811).

The expansion of endoscopic submucosal dissection in France: A prospective nationwide survey.

INTRODUCTION: Early reports of endoscopic submucosal dissection (ESD) in Europe suggested high complication rates and disappointing outcomes compared to publications from Japan. Since 2008, we have been conducting a nationwide survey to monitor the outcomes and complications of ESD over time. MATERIAL AND METHODS: All consecutive ESD cases from 14 centers in France were prospectively included in the database. Demographic, procedural, outcome and follow-up data were recorded. The results obtained over three years were compared to previously published data covering the 2008-2010 period. RESULTS: Between November 2010 and June 2013, 319 ESD cases performed in 314 patients (62% male, mean (±SD) age 65.4 ± 12) were analyzed and compared to 188 ESD cases in 188 patients (61% male, mean (±SD) age 64.6 ± 13) performed between January 2008 and October 2010. The mean (±SD) lesion size was 39 ± 12 mm in 2010-2013 vs 32.1 ± 21 for 2008-2010 (p = 0.004). En bloc resection improved from 77.1% to 91.7% (p < 0.0001) while R0 en bloc resection remained stable from 72.9% to 71.9% (p = 0.8) over time. Complication rate dropped from 29.2% between 2008 and 2010 to 14.1% between 2010 and 2013 (p < 0.0001), with bleeding decreasing from 11.2% to 4.7% (p = 0.01) and perforations from 18.1% to 8.1% (p = 0.002) over time. No procedure-related mortality was recorded. CONCLUSIONS: In this multicenter study, ESD achieved high rates of en bloc resection with a significant trend toward better outcomes over time. Improvements in lesion delineation and characterization are still needed to increase R0 resection rates.

A novel hemostatic powder for upper gastrointestinal bleeding: a multicenter study (the "GRAPHE" registry).

Background and study aims: The hemostatic powder TC-325 (Hemospray; Cook Medical, Winston-Salem, North Carolina, USA) has shown promising results in the treatment of upper gastrointestinal bleeding (UGIB) in expert centers in pilot studies. The aim of this study was to evaluate the feasibility and efficacy of TC-325 in a large prospective registry of use in routine practice. Patients and methods: The data of all patients treated with TC-325 were prospectively collected through a national registry. Outcomes were the immediate feasibility and efficacy of TC-325 application, as well as the rates of rebleeding at Day 8 and Day 30. Multivariate analysis was performed to determine predictive factors of rebleeding. Results: A total of 202 patients were enrolled and 64 endoscopists participated from 20 centers. TC-325 was used as salvage therapy in 108 patients (53.5 %). The etiology of bleeding was an ulcer in 75 patients (37.1 %), tumor in 61 (30.2 %), postendoscopic therapy in 35 (17.3 %), or other in 31 (15.3 %). Application of the hemostatic powder was found to be very easy or easy in 31.7 % and 55.4 %, respectively. The immediate efficacy rate was 96.5 %. Recurrence of UGIB was noted at Day 8 and Day 30 in 26.7 % and 33.5 %, respectively. Predictive factors of recurrence at Day 8 were melena at initial presentation and use of TC-325 as salvage therapy. Conclusion: These multicenter data confirmed the high rate of immediate hemostasis, excellent feasibility, and good safety profile of TC-325, which could become the treatment of choice in bleeding tumors or postendoscopic bleeding but not in bleeding ulcers where randomized studies are needed. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02595853).

Safety and efficacy of palliative systemic chemotherapy combined with colorectal self-expandable metallic stents in advanced colorectal cancer: A multicenter study.

PURPOSE: Self-expandable metallic stent (SEMS) placement is an accepted palliative therapy for management of acute malignant bowel obstruction in advanced colorectal cancer. Nevertheless, data are lacking on the effects of systemic chemotherapy combined with colorectal SEMS. The aim of this study was to investigate the safety and efficacy of palliative chemotherapy for advanced colorectal cancer combined with colorectal SEMS placement. PATIENTS AND METHODS: This multicentre retrospective study included all consecutive advanced colorectal cancer patients who received first-line palliative chemotherapy combined with endoscopic stenting for colorectal cancer with obstruction. We analyzed the number of cycles and the type of combination used. The primary endpoint was overall survival. Secondary endpoints included progression-free survival, response rate, grade 3-4 toxicity and the outcomes of SEMS for malignant colorectal obstruction. RESULTS: A total of 38 patients were included. Among them, 25 patients received oxaliplatin and 5-fluorouracil combination chemotherapy. Objective response and stabilization occurred in 38 and 24% of patients, respectively. The median overall survival and progression-free survival from the start of chemotherapy were 18 and 5months, respectively. The objective response rate and overall disease control rate were 38 and 62%, respectively. Toxicity was generally acceptable. Major complications related to stenting included perforation (8%), stent migration (5%), and reobstruction secondary to tumor ingrowths (13%). CONCLUSIONS: Chemotherapy combined with colonic stenting as a first-line treatment seems to be a valid option in advanced colorectal cancer patients with malignant colorectal obstruction.

Endoscopic treatment of fistula after sleeve gastrectomy: results of a multicenter retrospective study.

BACKGROUND AND STUDY AIMS: Fistula is the main complication of laparoscopic sleeve gastrectomy (LSG), for which healing is difficult to achieve. The aims of the study were to evaluate the efficacy of interventional endoscopy for post-LSG fistula treatment, to evaluate various endoscopic techniques used and identify their complications, and to identify predictive factors of healing following endoscopic treatment. PATIENTS AND METHODS: This retrospective multicenter study included patients with post-LSG fistula. Therapeutic procedures were evaluated, taking into account complications and healing times. Endoscopic procedures were considered to have promoted healing if no other surgical procedure was performed. Predictive factors of healing were identified by univariate and multivariate analysis. RESULTS: A total of 110 patients were included, of whom 6 (5.5 %) healed spontaneously, 81 (73.6 %) healed following endoscopic treatment, and 19 (17.3 %) healed following surgery. Healing rates following endoscopic treatment were 84.4 % in the first 6 months of treatment (65/77), 52.4 % for treatment lasting 6 - 12 months (11/21), and 41.7 % after 12 months of treatment (5/12). A drainage procedure (surgical, endoscopic, or percutaneous) was performed in 92 patients (83.6 %). A total of 177 esogastric stents were placed in 88 patients (80.0 %). Surgical debridement, clip placement, glue sealing, and plug placement were also performed. Multivariate analysis identified four predictive factors of healing following endoscopic treatment: interval < 21 days between fistula diagnosis and first endoscopy (P = 0.003), small fistula (P = 0.01), interval between LSG and fistula ≤ 3 days (P = 0.01), no history of gastric banding (P = 0.04). CONCLUSION: Endoscopic treatment facilitated healing of post-LSG fistula in 74 % of patients. Early endoscopic treatment increased the likelihood of success, and was most effective during the first 6 months of management. After this point, surgical treatment should be considered.

Endoscopic transgastric versus surgical necrosectomy in infected pancreatic necrosis.

Surgical necrosectomy, but is still associated with a high morbidity. Indications of the endoscopic route, a new less invasive technique are not defined yet. To compare characteristics and clinical outcome of patients treated by the two techniques, a bi-centric retrospective comparison of 21 patients treated by surgical necrosectomy in one center (group S) with 11 patients treated in another center by endoscopic transgastric necrosectomy (group E) was performed. Clinical severity scores were significantly higher in group S although CT severity score did not differ between groups. Acute postoperative complications including pancreatic fistula occurred more frequently in group S (86% vs. 27%, P=0.002). ICU and hospital length of stay were higher in group S (84 vs. 4 days; P=0.008 and 58 vs. 15 days; P=0.005 respectively). Long-term complication did not differ between groups. Compared to surgery, endoscopic necrosectomy exhibited lower rate of complications and reduced hospital length of stays. Endoscopic transgastric necrosectomy appears as a safe and effective procedure and has to be included in the therapeutic algorithm of infected pancreatic necrosis.

Endoscopic submucosal dissection for superficial rectal tumors: prospective evaluation in France.

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) provides a high en bloc resection rate for superficial colorectal tumors. The aims of this study were to assess the feasibility of ESD in France and to evaluate the complete resection rate at 1 year. PATIENTS AND METHODS: Patients with superficial rectal tumors ≥ 10 mm in size were prospectively included in the study at nine French expert centers between February 2010 and June 2012. The study was stopped temporarily because of a high complication rate. Study recruitment resumed following remedial action. RESULTS: A total of 45 patients were included (mean age 67 years; 24 males). The immediate perforation rate was 18 % (n = 8), and salvage surgery was not required. Six patients (13 %) had late bleeding, which was treated endoscopically in five patients and surgically in one patient who had required blood transfusion. The mortality rate was zero. The en bloc resection rate was 64 % (29/45), and the curative R0 resection rate was 53 % (24/45). Three patients (7 %) had an invasive tumor (two sm1, one T2). At 1-year follow-up, endoscopic examinations showed complete resection in 38 /43 patients (88 %). At the end of the study, after the remedial action, the en bloc resection rate had increased from 52 % to 82 %, and the perforation rate had decreased significantly from 34 % to 0 %. CONCLUSIONS: The study reflects the initial prospective experience of ESD in France, and suggests that curative R0 resection rates should increase and complication rates should decrease with experience and corrective actions.

Infliximab infusion time in patients with inflammatory bowel diseases: is longer really safer?

BACKGROUND AND OBJECTIVE: Infliximab, a monoclonal antibody directed against tumor necrosis factor α (TNFα), is commonly used during flares and on a regular basis to maintain the remission of inflammatory bowel diseases (IBD). It is usually administered in 2-hours infusion and 2 hours of monitoring after as recommended. However, recent reports suggest that infliximab infusions over a shorter period (30 minutes to 1 hour) are well tolerated. We aimed to compare the tolerability of 1-hour and 2-hours infliximab infusions in patients with IBD in our institution. METHODS: We analyzed data from all patients treated with infliximab between 1999 and September 2010. Infliximab was administered in 1-hour infusion and 1 hour monitoring since 2009. Only the early adverse events were analyzed. RESULTS: Adverse events during infusion were compared between one group of patients who had 1-hour infusion (989 infusions) and the other who had 2-hours infusion (2102 infusions). The incidence of adverse events was 10.6% in the 2-hours infusion group versus 6.3% in the 1-hour infusion group (P=0.36). CONCLUSIONS: These results suggest that the occurrence of infliximab infusion-related adverse events is similar across the two groups, regardless of the infusion cycle. One-hour infusion could then be proposed safely for all patients.

[HNPCC (hereditary non-polyposis colorectal cancer) or Lynch syndrome: a syndrome related to a failure of DNA repair system]. / Le syndrome HNPCC (hereditary non polyposis colorectal cancer) ou syndrome de Lynch : un syndrome en rapport avec une défaillance du système de réparation de l'ADN.

The HNPCC syndrome (hereditary non polyposis colon cancer) or Lynch syndrome stands for an autosomic dominant condition leading to the most prevalent hereditary colo-rectal cancers (CCR). MMR (mismatch repair)'s genes are involved in carcinogenesis as they play a role in ADNA mismatch repair. Microsatellite instability (MSI+ phenotype) induced by germline mutations is characteristic of such tumors and is necessary to assert the diagnosis. The HNPCC syndrome is associated with a significant increased risk of CCR altogether with endometrium, upper urinary tract and small bowel carcinomas as well as ovarian, biliary system and gastric cancers although of lesser extent. It is of importance to diagnose HNPCC syndrome prior to the treatment starts because it may influence patient's (as well as her/his relatives) disease management (type of surgery, surveillance and screening exams). New French recommendations, developed in 2009, about prophylactic colo-rectal and gynecologic surgeries and monitoring update latest ones published on 2004.

Complete remission of gastric Burkitt's lymphoma after eradication of Helicobacter pylori.

Burkitt's lymphoma is a highly aggressive non-Hodgkin lymphoma, often presenting in extra-nodal sites. It generally has a poor spontaneous outcome and needs aggressive treatment with systemic and intrathecal chemotherapy. Occurrence at the gastric site is rare. We report the case of a 39-year old woman who presented with a prominent ulcerated lesion of the antrum corresponding histologically to a Burkitt's lymphoma associated with Helicobacter pylori (H pylori) infection. Interphase fluorescence in situ hybridization (FISH) demonstrated c-MYC gene rearrangement in tumour cells without BCL2 or BCL6 gene translocations. Ulcer healing and tumour regression with a complete histological response were obtained 8 wk after H pylori eradication. In spite of this complete remission, taking into account the high risk of recurrence, the patient received systemic and intrathecal chemotherapy. Two years later, the patient remained in complete remission. This is the first report of a gastric Burkitt's lymphoma responding to H pylori eradication. These findings raise the question of the potential role of H pylori in the pathogenesis of some gastric Burkitt's lymphomas, and show the importance of searching for and eradicating the bacteria in combination with conventional chemotherapy regimens.

Multidisciplinary therapy of a large esophago-pericardial fistula arising from Barrett's esophagus.

Esophago-pericardial fistula is a rare complication of benign esophageal pathologies. We present the case report of a patient with Barrett's esophagus complicated by an esophago-pericardial fistula managed by a multi-therapeutic approach to close the fistula using an autologous pericardial patch; placement of a coated, expandable, metallic esophageal stent; and a feeding jejunostomy.

Involvement of the leptin receptor in the immune response in intestinal cancer.

The incidence of colorectal cancers (CRC) may be influenced by environmental factors, including nutrition. The role of peptides regulating food intake in controlling the growth and recurrence of human tumors is controversial. Leptin, a cytokine-like peptide, regulates food intake. We investigated the expression of leptin and its receptor in 171 consecutive patients (78 female and 93 male; 71 years) with CRC. Leptin concentrations in the serum (ELISA) were determined before tumor removal. ObRb was characterized in tumors and normal homologous tissues and culture cells (HT29, HCT116, and HCT116 with a transferred chromosome 3) by using immunocytochemistry, immunohistochemistry, reverse transcription-PCR (RT-PCR), and Western blotting. Microsatellite instability (MSI) phenotype was characterized by immunohistochemistry and pentaplex PCR. mRNAs of cytokines and chemokines were quantified in tumors and in normal homologous tissues (RT-PCR) in 43 patients. Adequate statistical tests, including multivariate analysis adjusted for pathologic tumor-node-metastasis (pTNM), MSI-H, and ObRb phenotypes, were used. Higher expression of ObRb in tumors compared with the homologous normal mucosa, pTNM staging but not leptin serum level, was associated with patients' progression-free survival (PFS). Tumor ObRb phenotype and pTNM were independent predictive factors of PFS. ObRb was more strongly expressed in HCT116 cells than in HCT116-Ch3 cells as well as in MSI-H tumors than in microsatellite stability and potentially associated with efficient cytotoxic antitumoral response as assessed by immunohistochemistry and RT-PCR measurements. We suggest that leptin receptor expression in tumors is involved in adaptive immune response in sporadic colon and rectal tumors likely via MSI-H phenotype orientation.