Robotic Versus Open Liver Resection in Hepatocarcinoma: Surgical and Oncological Outcomes.

BACKGROUND: Minimally invasive approaches are spreading in every field of surgery, including liver surgery. However, studies comparing robotic hepatectomy with the conventional open approach regarding oncologic outcomes for hepatocellular carcinoma are limited. MATERIALS AND METHODS: We retrospectively reviewed demographics characteristics, pathologic features, surgical, and oncological outcomes of patients who underwent robotic and conventional open liver resection for hepatocellular carcinoma. RESULTS: No significant differences in demographics features, tumor size, tumor location, and type of liver resection were found. The morbidity rate was similar, 23% for the open group versus 17% of the robotic group (P=0.605). Perioperative data analysis showed a greater estimated blood loss in patients who underwent open resection, if compared with robotic group (P=0.003). R0 resection and disease-free resection margins showed no statistically significant differences. The 3-year disease-free survival of the robotic group was comparable with that of the open group (54% vs. 37%; P=0.592), as was the 3-year overall survival (87% vs. 78%; P=0.203). CONCLUSIONS: The surgical and the oncological outcomes seem to be comparable between minimally invasive and open hepatectomy. Robotic liver resections are effective, and do not compromise the oncological outcome, representing a reasonable alternative to the open approach.

Significant and Conflicting Correlation of IL-9 With Prevotella and Bacteroides in Human Colorectal Cancer.

Background and aim: Gut microbiota (GM) can support colorectal cancer (CRC) progression by modulating immune responses through the production of both immunostimulatory and/or immunosuppressive cytokines. The role of IL-9 is paradigmatic because it can either promote tumor progression in hematological malignancies or inhibit tumorigenesis in solid cancers. Therefore, we investigate the microbiota-immunity axis in healthy and tumor mucosa, focusing on the correlation between cytokine profile and GM signature. Methods: In this observational study, we collected tumor (CRC) and healthy (CRC-S) mucosa samples from 45 CRC patients, who were undergoing surgery in 2018 at the Careggi University Hospital (Florence, Italy). First, we characterized the tissue infiltrating lymphocyte subset profile and the GM composition. Subsequently, we evaluated the CRC and CRC-S molecular inflammatory response and correlated this profile with GM composition, using Dirichlet multinomial regression. Results: CRC samples displayed higher percentages of Th17, Th2, and Tregs. Moreover, CRC tissues showed significantly higher levels of MIP-1α, IL-1α, IL-1ß, IL-2, IP-10, IL-6, IL-8, IL-17A, IFN-γ, TNF-α, MCP-1, P-selectin, and IL-9. Compared to CRC-S, CRC samples also showed significantly higher levels of the following genera: Fusobacteria, Proteobacteria, Fusobacterium, Ruminococcus2, and Ruminococcus. Finally, the abundance of Prevotella spp. in CRC samples negatively correlated with IL-17A and positively with IL-9. On the contrary, Bacteroides spp. presence negatively correlated with IL-9. Conclusions: Our data consolidate antitumor immunity impairment and the presence of a distinct microbiota profile in the tumor microenvironment compared with the healthy mucosa counterpart. Relating the CRC cytokine profile with GM composition, we confirm the presence of bidirectional crosstalk between the immune response and the host's commensal microorganisms. Indeed, we document, for the first time, that Prevotella spp. and Bacteroides spp. are, respectively, positively and negatively correlated with IL-9, whose role in CRC development is still under debate.

Fingerprinting Acute Digestive Diseases by Untargeted NMR Based Metabolomics.

Precision medicine may significantly contribute to rapid disease diagnosis and targeted therapy, but relies on the availability of detailed, subject specific, clinical information. Proton nuclear magnetic resonance (¹H⁻NMR) spectroscopy of body fluids can extract individual metabolic fingerprints. Herein, we studied 64 patients admitted to the Florence main hospital emergency room with severe abdominal pain. A blood sample was drawn from each patient at admission, and the corresponding sera underwent ¹H⁻NMR metabolomics fingerprinting. Unsupervised Principal Component Analysis (PCA) analysis showed a significant discrimination between a group of patients with symptoms of upper abdominal pain and a second group consisting of patients with diffuse abdominal/intestinal pain. Prompted by this observation, supervised statistical analysis (Orthogonal Partial Least Squares⁻Discriminant Analysis (OPLS-DA)) showed a very good discrimination (>90%) between the two groups of symptoms. This is a surprising finding, given that neither of the two symptoms points directly to a specific disease among those studied here. Actually herein, upper abdominal pain may result from either symptomatic gallstones, cholecystitis, or pancreatitis, while diffuse abdominal/intestinal pain may result from either intestinal ischemia, strangulated obstruction, or mechanical obstruction. Although limited by the small number of samples from each of these six conditions, discrimination of these diseases was attempted. In the first symptom group, >70% discrimination accuracy was obtained among symptomatic gallstones, pancreatitis, and cholecystitis, while for the second symptom group >85% classification accuracy was obtained for intestinal ischemia, strangulated obstruction, and mechanical obstruction. No single metabolite stands up as a possible biomarker for any of these diseases, while the contribution of the whole ¹H⁻NMR serum fingerprint seems to be a promising candidate, to be confirmed on larger cohorts, as a first-line discriminator for these diseases.

Analysis of Prognostic Factors for Resected Synchronous and Metachronous Liver Metastases from Colorectal Cancer.

BACKGROUND: Surgical treatment is the cornerstone in the management of colorectal cancer (CRC) liver metastases. The aim of this study is to identify clinicopathological factors affecting disease-free (DFS) and overall survival (OS) in patients undergoing potentially curative liver resection for CRC metastasis. METHODS: All consecutive patients undergoing liver resection for first recurrence of CRC from February 2006 to February 2018 were included. Prognostic impact of factors related to the patient, primary and metastatic tumors, was retrospectively tested through univariate and multivariate analyses. RESULTS: Seventy patients were included in the study. Median postoperative follow-up was 37 months (range 1-119). Median DFS and OS were 15.2 and 62.7 months, and 5-year DFS and OS rates were 16% and 53%. In univariate analysis, timing of metastasis presentation/treatment (combined colorectal and liver resection, "bowel first" approach or metachronous presentation) (p < 0.0001), ASA score (p = 0.003), chemotherapy after liver surgery (p = 0.028), T stage (p = 0.021), number of resected liver lesions (p < 0.0001), and liver margin status (p = 0.032) was significantly associated with DFS while peritoneal resection at colorectal surgery (p = 0.026), ASA score (p = 0.036), extension of liver resection (p = 0.024), chemotherapy after liver surgery (p = 0.047), and positive nodes (p = 0.018) with OS. In multivariate analysis, timing of metastasis presentation/treatment, ASA score, and chemotherapy (before and after liver surgery) resulted significantly associated with DFS and timing of metastasis presentation/treatment, positive nodes, peritoneal resection at colorectal surgery, and surgical approach (open or minimally invasive) of colorectal resection with OS. CONCLUSIONS: Surgery may provide good DFS and OS rates for CRC liver metastasis. Patient selection for surgery and correct timing of intervention within a multidisciplinary approach may be improved by taking into account negative prognostic factors which stress the importance of systemic therapy.

Comparing laparoscopic surgery with open surgery for long-term outcomes in patients with stage I to III colon cancer.

BACKGROUND: Although the short-term advantages of laparoscopy for colon cancer (CC) over open surgery have been clearly demonstrated, there is little evidence available concerning the long-term outcomes. This study aimed to compare the long-term results of laparoscopic surgery versus open surgery in a cohort of CC patients from a single center. METHODS: A series of 443 patients consecutively operated on for stage I to III CC between January 2006 and December 2013 were followed up. Patients were divided into two groups according to the surgical technique and were compared for disease-free survival (DFS) and overall survival (OS) before and after 1:1 propensity score matching. RESULTS: Due to exclusions and drop-outs, the statistical analysis of the study is based on 398 patients. Open surgery was performed in 133 patients, and laparoscopic surgery was performed in 265. After propensity score matching, two comparable groups of 89 patients each were obtained. The 5-year DFS was 64.3% and 78.2% for patients in the open and laparoscopic resection groups, respectively [hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.33-1.19; P = 0.148]. A 5-year OS of 72.1% and 86.8% was observed in the open and laparoscopic resection groups, respectively (HR 0.43, 95%CI 0.20-0.94; P = 0.026). The multivariate survival analysis demonstrated better results of laparoscopy compared with open surgery for both DFS (HR 0.43, 95%CI 0.23-0.78; P = 0.004) and OS (HR 0.28, 95%CI 0.14-0.59; P < 0.001). CONCLUSIONS: Despite the limitations of a retrospective analysis, our study confirms better results for laparoscopic surgery in terms of DFS and OS compared with open surgery in CC treatment.

Poor pathogenetic role of luminal obstruction in the development of appendicitis: A case report.

RATIONALE: In developed countries, the incidence of acute appendicitis is about 95 cases out of 100,000 per year, being one of the most common urgencies in general surgery worldwide. However, its pathogenesis is still poorly understood. Direct luminal obstruction (by a fecalith, lymphoid hyperplasia, or impacted stool) is reported to be the primary and principal cause of acute appendicitis. PATIENT CONCERNS: During October 2016 a 58-year-old woman was operated because of a clinical recurrence of Crohn's disease. At surgery, performed through single incision laparoscopy, we observed an exceptional finding. DIAGNOSES: Despite a previous ileo-cecal resection, the appendix was still present and vascularized by small vessels within the mesoappendix connected to the neo-terminal ileum mesentery; it was about 5 cm long and macroscopically not inflamed even if its base was clearly no longer connected with the cecum. OUTCOMES: The patient underwent ileo-colic resection with en-bloc removal of the appendix. With a narrow metallic stylet probe we carefully tried to enter the appendix lumen through the opposite side from its fundus but we were not able to enter it before cutting the wall with scissors. Pathological examination confirmed the Crohn's disease recurrence affecting the small bowel and the appendix lumen obstructed in the presence of a fecalith but without any sign of inflammation. LESSONS: This finding seems to highlight the poor pathogenetic role of luminal obstruction in the development of acute appendicitis.

Totally robotic intracorporeal side-to-side isoperistaltic strictureplasty for Crohn's disease.

The development of bowel-sparing techniques (strictureplasties) for extended stricturing Crohn's disease (CD) and the increased use of minimally invasive surgery (wound sparing) represent the two most important improvements in inflammatory bowel disease surgery from the origin. Nevertheless, the minimally invasive approach for extended stricturing forms is usually avoided primarily because of difficulties in performing complex intracorporeal sutures. We describe a totally intracorporeal robotic ileocecal resection with a yet described modified side-to-side isoperistaltic strictureplasty for an extended ileocecal CD. The strictureplasty was 6 cm long including the stricture in its middle part. Adopting this approach, the preserved small bowel was about 10 cm longer. Operative time was about 4 h, with a blood loss of about 50 ml. The patients' post-operative course was uneventful, enteral nutrition started at post-operative day 2 and gradual oral food intake from day 3. She was discharged on post-operative day 6. Histology confirmed a stricturing CD, and the patient is recurrence free at 34 months' follow-up. Our report suggests that robotic-assisted intracorporeal strictureplasty is feasible and that robotics could represent an interesting instrument for allowing the intersection between minimally invasive and bowel-sparing surgery for CD.

Pylephlebitis and Crohn's disease: A rare case of septic shock.

INTRODUCTION: Troncular pylephlebitis, defined as septic thrombophlebitis of the portal vein, is usually secondary to suppurative infection from the regions drained by the portal system. Therefore, pylephlebitis can occur from the portal vein main tributaries. The occurrence of mesenteric pylephlebitis in Crohn's disease is extremely rare. PRESENTATION OF CASE: We describe a case of septic shock due to mesenteric pylephlebitis in a 47 years old male affected with Crohn's disease. The patient was admitted to the emergency department after he had been complained from 3h of a peri-umbilical abdominal pain associated to fever and shivering quickly followed by a severe hypotension. His medical history included histologically confirmed ileal Crohn's disease diagnosed 4 years before and treated with mesalamine only. Computed tomography scan confirmed the mesenteric pylephlebitis diagnosis. After medical therapy with antibiotics and systemic nutrition, the patient was successfully operated to treat his ileal Crohn's disease. DISCUSSION: In our case, the quick onset of a septic shock was not due to a peritonitis complicating a Crohn's disease, but to a rare condition not needing an urgent surgical resolution. This report shows that, even in Crohn's disease, once diagnosis is performed, antibiotic therapy associated to enteral and parenteral nutrition can lead to a complete clinical remission of mesenteric pylephlebitis, mandatory to perform an elective surgery. CONCLUSION: This case highlights the importance of promptly considerate and treat mesenteric pylephlebitis in presence of a septic shock in a Crohn's disease patient who is not showing clinical signs of peritonitis.

Rationalisation of the surgical technique for minimally invasive laparoscopic ileal pouch-anal anastomosis after previous total colectomy for ulcerative colitis.

INTRODUCTION: No previous study clearly focuses on laparoscopic technique to perform the second stage surgery (proctectomy with ileal pouch-anal anastomosis [IPAA]) after total colectomy for acute/severe ulcerative colitis (UC). We describe the procedural steps for a simple and rational minimally invasive second stage surgery, reporting intra- and short-term post-operative results. PATIENTS AND METHODS: During the period December 2014-December 2015, 10 consecutive patients (8 males and 2 females) with mean age of 48 years underwent laparoscopic proctectomy and IPAA adopting our novel approach. They were operated 3 months after the previous total colectomy which has been performed, respectively, for acute (three patients) or severe (seven patients) UC. Intraoperative data and post-operative complications, divided as minor and major, were recorded and analysed. A body image questionnaire was administered to all patients to evaluate the cosmetic results of the procedure. RESULTS: Overall mean surgical time was 235 ± 49 min. During the post-operative course, three patients required morphine for >48 h, no patient needed blood transfusion and bowel movements recovery happened as mean during the 2nd day. No early major complications happened. Two patients (20%) developed peri-ileostomic wound infection at the right flank. Only one patient (10%) suffered from ileal-anal anastomotic dehiscence, conservatively treated till resolution. The average length of hospital stay was 8 ± 2 days. The body image questionnaire showed in all patients an extreme satisfaction about the results obtained (mean value = 59/64 points). CONCLUSIONS: Through three standardised surgical steps easily reproducible, we describe an almost scar-less procedure able to optimise the intraoperative time with good post-operative results in terms of complications and cosmesis.

Crohn's Colitis: Development of a multiplex gene expression assay comparing mRNA levels of susceptibility genes.

Crohn's disease (CD) is a multifactorial immunologically mediated disease. In this study we explored, for the first time, the efficacy of the Multiplex Gene Assay technology for detecting mRNA expression profile of 24 selected CD related genes in endoscopic biopsies and surgical specimens from CD patients with colonic localization of the disease. The polymorphisms of genes most frequently associated with CD were also analysed in DNA samples from the same patients. The analysis of endoscopic samples showed increased expression of 7 genes in inflamed mucosa compared to non-inflamed mucosa and suggests the activation of the autophagy process and of a Th17 adaptive response. The analysis of surgical specimens showed increased expression of 16 genes in inflamed tissue compared to non-inflamed internal controls and revealed the activation of immune-adaptive Th17 response in association with a Th1 response. Furthermore, an increased expression of genes involved in ionic transport and signal transduction was found in inflamed mucosa compared to non-inflamed internal controls. This study confirms the activation of Th17 and Th1 adaptive-immune response also in colonic CD. It should be stressed that these responses have been disclosed in biopsy tissue, while only Th17 differentiation is revealed in endoscopic tissue. Interestingly, the polymorphisms analysis revealed that a homozygous genotype is associated to a more complicated clinical course.

Results of Surgical Salvage Treatment for Anal Canal Cancer: A Retrospective Analysis with Overview of the Literature.

BACKGROUND AND AIM: Chemoradiotherapy (CRT) is the gold standard treatment for anal cancer, which permits the maintenance of the anal function. However, about 30-40% of patients develop local disease progression, for which surgery represents a good salvage therapy. The aim of this study is to evaluate survival and morbidity rate in patients who undergo salvage surgery in our single institution, with an overview of the literature. METHODS: A retrospective study was carried out on patients who underwent surgical treatment of anal canal cancer after failure of CRT. We evaluated overall survival at 1, 3, and 5 years and postoperative morbidity rate. RESULTS: Twenty patients who underwent radical surgery with abdominoperineal resection were included in the study. The survival rates at 1, 3, and 5 years were 75, 60, and 37.4%; with a disease-free survival of 67, 53, and 35%, respectively. There was no postoperative mortality. The morbidity rate was 35%. CONCLUSION: Surgery represents the recommended therapy for persistent or recurrent anal canal cancer after CRT, with a good survival rate and an acceptable morbidity.

Preliminary Comparison of Oral and Intestinal Human Microbiota in Patients with Colorectal Cancer: A Pilot Study.

In this study Next-Generation Sequencing (NGS) was used to analyze and compare human microbiota from three different compartments, i.e., saliva, feces, and cancer tissue (CT), of a selected cohort of 10 Italian patients with colorectal cancer (CRC) vs. 10 healthy controls (saliva and feces). Furthermore, the Fusobacterium nucleatum abundance in the same body site was investigated through real-time quantitative polymerase chain reaction (qPCR) to assess the association with CRC. Differences in bacterial composition, F. nucleatum abundance in healthy controls vs. CRC patients, and the association of F. nucleatum with clinical parameters were observed. Taxonomic analysis based on 16S rRNA gene, revealed the presence of three main bacterial phyla, which includes about 80% of reads: Firmicutes (39.18%), Bacteroidetes (30.36%), and Proteobacteria (10.65%). The results highlighted the presence of different bacterial compositions; in particular, the fecal samples of CRC patients seemed to be enriched with Bacteroidetes, whereas in the fecal samples of healthy controls Firmicutes were one of the major phyla detected though these differences were not statistically significant. The CT samples showed the highest alpha diversity values. These results emphasize a different taxonomic composition of feces from CRC compared to healthy controls. Despite the low number of samples included in the study, these results suggest the importance of microbiota in the CRC progression and could pave the way to the development of therapeutic interventions and novel microbial-related diagnostic tools in CRC patients.

The Different Functional Distribution of "Not Effector" T Cells (Treg/Tnull) in Colorectal Cancer.

Colorectal cancer (CRC) is the third most common cancer worldwide, ranking as high as the second leading cause of cancer-related deaths in industrialized countries. Consistent with immunosurveillance theory, the immune system is crucial to protect the host from developing tumors, and the major players in tumoral immunity are effector T cells. Anyway, cancer cells develop strategies of immunoevasion influencing the cancer-specific lymphocyte priming, activation, and effector function. Therefore, the T cell subsets that mature during the stages of tumor growth, differently contribute to disease progression and/or regression. In our study, we analyzed the intra-tumoral and peripheral T cell subsets' distribution in 30 patients with CRC, in order to clarify their functional role toward cancer. We found that percentage of infiltrating effector T cells decreased in cancer tissue than in healthy mucosa and that the tumor microenvironment negatively influences the cytolytic activity of T lymphocytes reactive to cancer cells. Moreover, we found that the tumor tissue was infiltrated by a large amount of "not effector" T (neT) cells with a regulatory or an anergic profile, which are unable to kill cancer cells, may be contributing to the CRC promotion. The presence of neT cells was investigated also in the peripheral blood of CRC patients, demonstrating that the peripheral T regulatory cells can inhibit the proliferation of effector T cells, confirming their immunosuppressive properties. Finally, monitoring the changes in circulating neT cells' frequencies after the tumor removal, we confirmed the role of cancer in the modulation of immune system, in particular, in supporting a Tregs-mediated immunosuppression.

hERG1 behaves as biomarker of progression to adenocarcinoma in Barrett's esophagus and can be exploited for a novel endoscopic surveillance.

Barrett's esophagus (BE) is the only well-known precursor lesion of esophageal adenocarcinoma (EA). The exact estimates of the annual progression rate from BE to EA vary from 0.07% to 3.6%. The identification of BE patients at higher risk to progress to EA is hence mandatory, although difficult to accomplish. In search of novel BE biomarkers we analyzed the efficacy of hERG1 potassium channels in predicting BE progression to EA. Once tested by immunohistochemistry (IHC) on bioptic samples, hERG1 was expressed in BE, and its expression levels increased during progression from BE to esophageal dysplasia (ED) and EA. hERG1 was also over-expressed in the metaplastic cells arising in BE lesions obtained in different BE mouse models, induced either surgically or chemically. Furthermore, transgenic mice which over express hERG1 in the whole gastrointestinal tract, developed BE lesions after an esophago-jejunal anastomosis more frequently, compared to controls. A case-control study was performed on 104 bioptic samples from newly diagnosed BE patients further followed up for at least 10 years. It emerged a statistically significant association between hERG1 expression status and risk of progression to EA. Finally, a novel fluorophore- conjugated recombinant single chain variable fragment antibody (scFv-hERG1-Alexa488) was tested on freshly collected live BE biopsies: it could recognize hERG1 positive samples, perfectly matching IHC data.Overall, hERG1 can be considered a novel BE biomarker to be exploited for a novel endoscopic surveillance protocol, either in biopsies or through endoscopy, to identify those BE patients with higher risk to progress to EA.

The esophageal microbiota in health and disease.

The esophageal mucosa is among the sites colonized by human microbiota, the complex microbial ecosystem that colonizes various body surfaces and is increasingly recognized to play roles in several physiological and pathological processes. Our understanding of the composition of the esophageal microbiota in health and disease is challenged by the need for invasive sampling procedures and by the dynamic nature of the esophageal environment and remains limited in comparison with the information available for other body sites. Members of the genus Streptococcus appear to be the major components of the microbiota of the healthy esophagus, although the presence of several other taxa has also been reported. Dysbiosis, consisting of enrichment in some Gram-negative taxa (including Veillonella, Prevotella, Haemophilus, Neisseria, Campylobacter, and Fusobacterium), has been reported in association with gastroesophageal reflux disease and is hypothesized to contribute to the evolution of this condition toward Barrett's esophagus (which is the most common esophageal precancerous lesion) and, eventually, adenocarcinoma. Some Campylobacter species (mostly C. concisus) are also putatively involved in the progression of disease toward adenocarcinoma. However, variable findings have recently been reported in additional studies. Causative relationships between dysbiosis or specific bacterial species and esophageal diseases remain controversial and warrant further investigations.

Safer intestinal invagination for a solid pancreatico-jejunal anastomosis in presence of a soft texture pancreatic remnant and non-dilated duct.

Pancreatico-jejunal anastomosis after pancreatoduodenectomy still represents the Achilles' heel of the procedure: the failure of this anastomosis is relatively common and it is the main cause of post-operative morbidity and mortality. Studies have described different reconstruction strategies for the control of the development of post-operative pancreatic fistula, but the strategy to obtain a safer pancreatico-jejunal anastomosis is still far from satisfaction. We report a novel variation of the invagination technique based on preliminary clinical experience in 8 patients who underwent pancreatico-jejunal anastomosis after pancreatoduodenectomy in our hepatobiliopancreatic center from 2008 to 2014. The variation could obtain a safer intestinal invagination for a solid pancreatico-jejunal anastomosis even in the presence of soft pancreatic remnant.

Peripheral ENO1-specific T cells mirror the intratumoral immune response and their presence is a potential prognostic factor for pancreatic adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with an average survival of 4-6 months following diagnosis. Surgical resection is the only treatment with curative intent, but resectable PDAC patients are in the minority. Also, unlike other neoplasms, PDAC is resistant to conventional and targeted chemotherapy. Innovative treatments, such as immunotherapy, can be very important and the study of the immune response is fundamental. We previously demonstrated that PDAC patients show tumor-infiltrating T cells specific to α-enolase (ENO1), a glycolytic enzyme over-expressed by pancreatic tumor cells, which plays an important role in promoting cell migration and cancer metastasis. In the present study, we evaluate the functional anticancer proprieties of ENO1-specific T cells isolated from the peripheral blood of PDAC patients. Furthermore, comparing the T cell receptor repertoire of ENO1-specific peripheral and infiltrating tumor T cells from the same patient suggests that ENO1-specific T cells, despite having a different functional profile, can recirculate from the tumor to the periphery. Finally, of clinical relevance, the presence of peripheral ENO1-specific T cells has a prognostic value and significantly correlates with a longer survival.

Intra-tumoral IFN-γ-producing Th22 cells correlate with TNM staging and the worst outcomes in pancreatic cancer.

PDAC (pancreatic ductal adenocarcinoma) is the fifth leading cause of cancer-related death. The causes of this cancer remain unknown, but increasing evidence indicates a key role of the host immune response and cytokines in human carcinogenesis. Intra-tumoral IL (interleukin)-22 levels have been shown to be elevated in PDAC patients. However, little is known regarding the expression and clinical relevance of Th22 cells in human PDAC and, furthermore, which TILs (tumour-infiltrating lymphocytes) are the main producers of IL-22 is unknown. In the present study, we characterized the functional proprieties of the different subsets of IL-22-producing TILs and analysed their relationship with the TNM staging system and patient survival. We have demonstrated for the first time that, in PDAC patients, the T-cells co-producing IFN-γ (interferon γ) and exerting perforin-mediated cytotoxicity are the major intra-tumoral source of IL-22. In addition, isolated Th22 cells were able to induce apoptosis, which was antagonized by IL-22. Finally, we observed that the IL-22-producing T-cells were significantly increased in tumour tissue and that this increase was positively correlated with TNM staging of PDAC and poorer patient survival. These novel findings support the dual role of the anti-tumour immune system and that IL-22-producing cells may participate in PDAC pathogenesis. Therefore monitoring Th22 levels could be a good diagnostic parameter, and blocking IL-22 signalling may represent a viable method for anti-PDAC therapies.