Short-Chain Fatty Acids and Human Health: From Metabolic Pathways to Current Therapeutic Implications.

The gastrointestinal tract is home to trillions of diverse microorganisms collectively known as the gut microbiota, which play a pivotal role in breaking down undigested foods, such as dietary fibers. Through the fermentation of these food components, short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are produced, offering numerous health benefits to the host. The production and absorption of these SCFAs occur through various mechanisms within the human intestine, contingent upon the types of dietary fibers reaching the gut and the specific microorganisms engaged in fermentation. Medical literature extensively documents the supplementation of SCFAs, particularly butyrate, in the treatment of gastrointestinal, metabolic, cardiovascular, and gut-brain-related disorders. This review seeks to provide an overview of the dynamics involved in the production and absorption of acetate, propionate, and butyrate within the human gut. Additionally, it will focus on the pivotal roles these SCFAs play in promoting gastrointestinal and metabolic health, as well as their current therapeutic implications.

IMMUNOREACT 7: Regular aspirin use is associated with immune surveillance activation in colorectal cancer.

BACKGROUND: Long-term daily use of aspirin reduces incidence and mortality due to colorectal cancer (CRC). This study aimed to analyze the effect of aspirin on the tumor microenvironment, systemic immunity, and on the healthy mucosa surrounding cancer. METHODS: Patients with a diagnosis of CRC operated on from 2015 to 2019 were retrospectively analyzed (METACCRE cohort). Expression of mRNA of immune surveillance-related genes (PD-L1, CD80, CD86, HLA I, and HLA II) in CRC primary cells treated with aspirin were extracted from Gene Expression Omnibus-deposited public database (GSE76583). The experiment was replicated in cell lines. The mucosal immune microenvironment of a subgroup of patients participating in the IMMUNOREACT1 (ClinicalTrials.gov NCT04915326) project was analyzed with immunohistochemistry and flow cytometry. RESULTS: In the METACCRE Cohort, 12% of 238 patients analyzed were aspirin users. Nodal metastasis was significantly less frequent (p = .008) and tumor-infiltrating lymphocyte infiltration was higher (p = .02) among aspirin users. In the CRC primary cells and selected cell lines, CD80 mRNA expression was increased following aspirin treatment (p = .001). In the healthy mucosa surrounding rectal cancer, the ratio of CD8/CD3 and epithelial cells expressing CD80 was higher in aspirin users (p = .027 and p = .034, respectively). CONCLUSIONS: These data suggested that regular aspirin use may have an active role in enhancing immunosurveillance against CRC.

Innate Immunity Activation in Newly Diagnosed Ileocolonic Crohn's Disease: A Cohort Study.

BACKGROUND: Recent studies showed that early surgery for Crohn's disease leads to a lower recurrence rate. However, the underlying mechanism is unknown. OBJECTIVE: The study aims to analyze the innate immunity microenvironment in ileal mucosa according to the duration of Crohn's disease. DESIGN: A prospective cohort study. SETTINGS: Tertiary referral center for IBD surgery. PATIENTS: A total of 88 consecutive patients with Crohn's disease undergoing ileocolonic resection were prospectively enrolled. Mucosal samples were obtained from both healthy and inflamed ileum. Data from a public data set were analyzed as an external validation cohort. MAIN OUTCOME MEASURES: Neutrophil infiltration was evaluated by histological asessment and macrophage subpopulation was assessed by immunohistochemistry. Expressions of TLR2 , TLR4 , TLR5 , DEFB1 , DEFB4A , DEFB103 , DEFA5 , and DEFA6 were quantified by real-time quantitative polymerase chain reaction. Concentrations of BDNF, CCL-11, ICAM-1, IL-1A, IL-1ß, IL-1RN, IL-12p40, IL-12p70, IL-15, IL-17A, IL-23A, MMP-3, CCL-3, KITLG, and VEGFA were determined with an immunometric assay. RESULTS: Neutrophil infiltration is inversely correlated with disease duration. DEFB4A mRNA expression tended to be higher in late-stage Crohn's disease ( p = 0.07). A higher number of macrophages expressed CD163 at low intensity in late-stage Crohn's disease ( p = 0.04). The concentration of IL-15 ( p = 0.02) and IL-23A ( p = 0.05) was higher in healthy ileal mucosa of early-stage patients. In the external cohort, expressions of DEFB1 ( p = 0.03), DEFB4A ( p = 0.01), IL-2 ( p = 0.04), and IL-3 ( p = 0.03) increased in patients with late-stage Crohn's disease. LIMITATIONS: A relatively small number of patients, especially in the newly diagnosed group. CONCLUSIONS: In newly diagnosed Crohn's disease, high levels of IL-15 and IL-23 in healthy mucosa suggest that innate immunity is the starter of acute inflammation. Moreover, M2 macrophages increase in the healthy mucosa of patients with late-stage Crohn's disease, suggesting that reparative and profibrotic processes are predominant in the long term, and in this phase, anti-inflammatory therapy may be less efficient. See Video Abstract . ACTIVACIN DE LA INMUNIDAD INNATA EN LA RECIENTEMENTE DIAGNOSTICADA ENFERMEDAD DE CROHN ILEOCLICA UN ESTUDIO DE COHORTE: ANTECEDENTES:Estudios recientes demostraron que la cirugía temprana para la enfermedad de Crohn (EC) conduce a una menor tasa de recurrencia. Sin embargo, se desconoce el mecanismo subyacente.OBJETIVO:El estudio tiene como objetivo analizar el microambiente de la inmunidad innata en la mucosa ileal según la duración de la EC.DISEÑO:Un estudio de cohorte prospectivo.AJUSTES:Centro terciario de referencia para cirugía de EII.PACIENTES:Fueron registrados de manera prospectiva y consecutiva 88 pacientes con EC sometidos a resección ileocolónica. Se obtuvieron muestras de mucosa ileal, tanto del íleon sano como del íleon inflamado. Los datos se analizaron como una cohorte de validación externa.PRINCIPALES MEDIDAS DE RESULTADO:Fueron evaluados la infiltración de neutrófilos por histología y la subpoblación de macrófagos por inmunohistoquímica. La expresión de TLR2, TLR4, TLR5, DEFB1, DEFB4A, DEFB103, DEFA5 y DEFA6 fueron cuantificados mediante qPCR en tiempo real. Las concentraciones de BDNF, CCL-11, ICAM-1, IL-1A, IL-1B, IL-1RN, IL-12 p40, IL-12 p70, IL-15, IL-17A, IL-23A, MMP-3, CCL-3, KITLG, VEGFA se determinaron con ensayo inmunométrico.RESULTADOS:La infiltración de neutrófilos se correlaciona inversamente con la duración de la enfermedad. La expresión del ARNm de DEFB4A mostro una tendencia a ser mayor en la EC en etapa tardía ( p = 0,07). Un mayor número de macrófagos expresaron CD163 a baja intensidad en la etapa tardía ( p = 0,04). La concentración de IL15 ( p = 0,02) e IL23A ( p = 0,05) fue mayor en la mucosa ileal sana de pacientes en estadio temprano. En la cohorte externa, la expresión de DEFB1 ( p = 0,03) y DEFB4A ( p = 0,01), IL2 ( p = 0,04) e IL3 ( p = 0,03) aumentó en pacientes en etapa tardía.LIMITACIONES:Un número relativamente pequeño de pacientes, especialmente en el grupo recién diagnosticado.CONCLUSIONES:En la EC recién diagnosticada, los altos niveles de IL-15 e IL-23 en la mucosa sana sugieren que la inmunidad innata es el promotor de la inflamación aguda. Además, los macrófagos M2 aumentan en la mucosa sana de pacientes con EC en etapa tardía, lo que sugiere que los procesos reparadores y profibróticos son predominantes a largo plazo y en esta fase, la terapia antiinflamatoria puede ser menos eficiente. (Traducción-Dr. Osvaldo Gauto ).

Leaving behind a diseased small bowel during surgery for Crohn's disease: Long-term outcomes.

PURPOSES: Stricture is a common complication of Crohn's disease (CD) and may be treated with bowel-sparing procedures. Our study analyzed what happens in terms of intestinal and systemic inflammation when the diseased bowel is left behind following surgery. METHODS: In this retrospective study, we enrolled 42 consecutive patients who underwent strictureplasty (alone or with resection) for stricturing CD. Control patients who underwent complete diseased bowel resection were identified and propensity score-matched for the sex, age, and history of abdominal surgery. Biohumoral values were collected at follow-up examinations at 1, 6, and 12 months after surgery. Magnetic resonance imaging (MRI) was performed before and after strictureplasty in 19 patients. RESULTS: In the strictureplasty group, fecal calprotectin levels were decreased at 12 months (p = 0.03), whereas in the resectiongroup, they were decreased at 6 months (p = 0.02). On MRI, the ADC [apparent diffusion coefficient] (p < 0.001), wall thickness (p = 0.046) and Magnetic Resonance Index of Activity (MaRIA) (p < 0.001) and Clermont (p < 0.001) scores were improved after strictureplasty. Surgical recurrence was more frequent in the strictureplasty group than in the resection group (p = 0.003). CONCLUSIONS: Our retrospective study showed that even if the diseased bowel was left behind after surgery, the intestinal inflammatory activity still decreased. However, the permanence of the diseased bowel still increased the risk of reoperation, probably because of the fibrotic nature of the stenosis and the multifocality of CD.

Extraintestinal Cancers in Inflammatory Bowel Disease: A Literature Review.

BACKGROUND: Inflammatory bowel disease (IBD) is a group of chronic multifactorial inflammatory disorders including two major entities: Crohn's disease (CD) and ulcerative colitis (UC). Preliminary evidence suggests that patients with IBD may be at increased risk of developing intestinal and extraintestinal cancers (EICs). Actually, little is known about the association between IBD and EICs, and there is ever-growing concern regarding the safety of immunomodulators and biological therapy, which may represent a risk factor for carcinogenesis. AIMS: The aim of this review is to summarize the evidence regarding the association between IBD and EICs, the safety of immunomodulators and biological therapy and the management of immunomodulators and biologic agents in IBD patients with prior or current EICs. RESULTS: IBD patients have a higher risk of developing different forms of extraintestinal solid organ tumors and hematological malignancies. Immunomodulators and biological therapy may increase the risk of developing some types of EICs and may be consciously used in patients with IBD and current or prior history of malignancy. CONCLUSIONS: Decisions regarding the use of immunomodulators or biological therapies should be made on an individual basis, considering a multidisciplinary approach involving oncologists.

IMMUNOREACT 6: weak immune surveillance characterizes early-onset rectal cancer.

BACKGROUND: Colon cancer in young patients is often associated with hereditary syndromes; however, in early-onset rectal cancer, mutations of these genes are rarely observed. The aim of this study was to analyse the features of the local immune microenvironment and the mutational pattern in early-onset rectal cancer. METHODS: Commonly mutated genes were analysed within a rectal cancer series from the University Hospital of Padova. Mutation frequency and immune gene expression in a cohort from The Cancer Genome Atlas ('TCGA') were compared and immune-cell infiltration levels in the healthy rectal mucosa adjacent to rectal cancers were evaluated in the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 ('IMMUNOREACT') series. RESULTS: In the authors' series, the mutation frequency of BRAF, KRAS, and NRAS, as well as microsatellite instability frequency, were not different between early- and late-onset rectal cancer. In The Cancer Genome Atlas series, among the genes with the most considerable difference in mutation frequency between young and older patients, seven genes are involved in the immune response and CD69, CD3, and CD8ß expression was lower in early-onset rectal cancer. In the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 series, young patients had a lower rate of CD4+ T cells, but higher T regulator infiltration in the rectal mucosa. CONCLUSION: Early-onset rectal cancer is rarely associated with common hereditary syndromes. The tumour microenvironment is characterized by a high frequency of mutations impairing the local immune surveillance mechanisms and low expression of immune editing-related genes. A constitutively low number of CD4 T cells associated with a high number of T regulators indicates an imbalance in the immune surveillance mechanisms.

IMMUNOREACT 5: female patients with rectal cancer have better immune editing mechanisms than male patients - a cohort study.

BACKGROUND: Studies evaluating sex differences in colorectal cancer (CRC) tumor microenvironment are limited, and no previous study has focused on rectal cancer patients' constitutive immune surveillance mechanisms. The authors aimed to assess gender-related differences in the immune microenvironment of rectal cancer patients. METHODS: A systematic review and meta-analysis were conducted up to 31 May 2021, including studies focusing on gender-related differences in the CRC tumor microenvironment. Data on the mutational profile of rectal cancer were extracted from the Cancer Genome Atlas (TCGA). A subanalysis of the two IMMUNOREACT trials (NCT04915326 and NCT04917263) was performed, aiming to detect gender-related differences in the immune microenvironment of the healthy mucosa in patients with early (IMMUNOREACT 1 cohort) and locally advanced rectal cancer following neoadjuvant therapy (IMMUNOREACT 2 cohort). In the retrospective IMMUNOREACT 1 cohort (therapy naive), the authors enrolled 442 patients (177 female and 265 male), while in the retrospective IMMUNOREACT 2 cohort (patients who had neoadjuvant therapy), we enrolled 264 patients (80 female and 184 male). In the prospective IMMUNOREACT 1 cohort (therapy naive), the authors enrolled 72 patients (26 female and 46 male), while in the prospective IMMUNOREACT 2 cohort (patients who had neoadjuvant therapy), the authors enrolled 105 patients (42 female and 63 male). RESULTS: Seven studies reported PD-L1 expression in the CRC microenvironment, but no significant difference could be identified between the sexes. In the TGCA series, mutations of SYNE1 and RYR2 were significantly more frequent in male patients with rectal cancer. In the IMMUNOREACT 1 cohort, male patients had a higher expression of epithelial cells expressing HLA class I, while female patients had a higher number of activated CD4+Th1 cells. Female patients in the IMMUNOREACT 2 cohort showed a higher infiltration of epithelial cells expressing CD86 and activated cytotoxic T cells (P=0.01). CONCLUSIONS: Male patients have more frequent oncogene mutations associated with a lower expression of T-cell activation genes. In the healthy mucosa of female patients, more Th1 cells and cytotoxic T cells suggest a potentially better immune response to the tumor. Sex should be considered when defining the treatment strategy for rectal cancer patients or designing prognostic scores.

Treatment and Prognosis of Fibrolamellar Hepatocellular Carcinoma: a Systematic Review of the Recent Literature and Meta-analysis.

BACKGROUND: Fibrolamellar hepatocellular carcinoma (FL-HCC) is a rare disease and current efforts are focused on the prognosis and on the development of efficient and specific treatments. This study aimed to review the latest evidence regarding FL-HCC treatment and prognosis. METHODS: A systematic review of the literature over the past 10 years regarding FL-HCC, and meta-analysis of 1-, 3-, and 5-year overall survival (OS) comparing FL-HCC and conventional HCC were performed. RESULTS: Overall, 1567 articles were screened, of them 21 were selected for the systematic review, and 6 for meta-analysis. Twenty-one studies included a total of 2168 patients with FL-HCC, with a median age ranging from 11 to 56 years. The majority of patients underwent surgical resection or liver transplantation. After a median follow-up ranging from 24 to 58 months, 1-year OS was 67-100% and 5-year OS was 28-65%. A total of 743 patients with FL-HCC and 163,472 with conventional HCC were included in the meta-analysis. There was a significantly improved 1-, 3-, and 5-years OS in the FL-HCC group compared to the conventional HCC group, although high heterogeneity was found. When excluding population-based studies, and including 96 FL-HCC and 221 conventional HCC patients, the heterogeneity was low, and the meta-analysis showed a significantly longer 1-year OS in patients with FL-HCC than conventional HCC; however, there were no differences at 3- and 5-years OS. CONCLUSIONS: Surgical resection for FL-HCC is currently the only curative treatment available. FL-HCC is plagued by high-recurrence rates and poor long-term outcomes which may be related to the absence of specific treatment for advanced and recurrent disease.

Rectal Sparing Approaches after Neoadjuvant Treatment for Rectal Cancer: A Systematic Review and Meta-Analysis Comparing Local Excision and Watch and Wait.

Local Excision (LE) or Watch and Wait (WW) for patients with complete clinical response or near-complete clinical response after neoadjuvant chemoradiotherapy (nCRT) were proposed to avoid morbidity and impairment of quality of life after rectal resection. The aim of this study is to perform a systematic review of the literature, and to compare rectal-sparing approaches, in terms of rectum-preservation rate, local control, and distant recurrences. A systematic review and meta-analysis were performed of studies published until July 2022 (PROSPERO, registration CRD42022341480), and the quality of evidence was assessed using a GRADE approach. Seven retrospective studies and one prospective trial were included. In six studies, patients were treated with standard long-course nCRT, and in two with Total Neoadjuvant Therapy (TNT). Overall, there were 213 and 188 patients in WW and LE group, respectively, and no difference was found between WW and LE when considering rectum-preservation rate (OR 0.80 95%CI 0.31-2.01, p = 0.63), local disease (OR 1.60 95%CI 0.75-3.42, p = 0.22), locoregional failure (OR 0.85 95%CI 0.20-3.66, p = 0.83) and distant recurrence (OR 0.76 95%CI 0.37-1.55, p = 0.45). Studies directly comparing WW and LE are still lacking, even though no differences between WW and LE in terms of rectum-preservation, local control, and distant recurrences have been found.

Validation of the Padova Prognostic Score for Colitis in Predicting Long-Term Outcome After Restorative Proctocolectomy.

Background: In 10%-20% of cases it is impossible to make a differential diagnosis between ulcerative colitis and Crohn's colitis. A 50% failure rate of J pouch ilea-anal anastomosis is observed in Crohn's colitis. In 2009, we created the Padua Prognostic Score for Colitis (PPSC) to predict the long-term clinical and functional outcome and quality of life of patients undergoing restorative proctocolectomy with J pouch. The aim of the present study is to establish and validate the accuracy of a prognostic score for chronic inflammatory bowel diseases (IBD). Patient population and methods: The PPSC was created in 2009 by integrating clinical and histological information of patients undergoing RPC. It included preoperative perianal abscess or fistula, rectal sparing, terminal ileum involvement, skip lesions and histological diagnosis of indeterminate colitis or Crohn's colitis on the operative specimen. The validity of this score was tested in predicting postoperative abscess or fistula, anal canal disease, pouchitis, pouch failure and new diagnosis of Crohn's disease. Correlation analysis, ROC curve analysis and survival analysis were used to validate the PPSC in a different cohort from the previous one. Results: We retrospectively enrolled in this study 138 consecutive patients undergoing CPR for ulcerative colitis (n = 127) or indeterminate colitis (n = 11) in our institution since 2005 to 2020. In this period, we observed 11 patients with postoperative abscess or fistula, 3 with anal canal disease, 40 with pouchitis, 6 with pouch failure and 6 with new diagnosis of Crohn's disease. In the new validation cohort, the PPSC confirmed to have a good accuracy in predicting the onset of postoperative CD (AUC = 74.5%, p = 0.018). Kaplan Meier curves demonstrate how a PPSC over 1 can reliably predicts the long-term onset of, pouchitis (p = 0.002) and anal abscess or fistulae (p = 0.04). Conclusions: In this validation study we confirmed the accuracy of the PPSC in predicting postoperative fistulas or abscesses and pouchitis. Therefore, we believe that in clinical practice patients with a PPSC score greater than 1 should be warned of this risk of possible Crohn's disease diagnosis and pouch failure.

The impact of anastomotic leak on long-term oncological outcomes after low anterior resection for mid-low rectal cancer: extended follow-up of a randomised controlled trial.

PURPOSE: The impact of anastomotic leaks (AL) on oncological outcomes after low anterior resection for mid-low rectal cancer is still debated. The aim of this study was to evaluate overall survival (OS), disease-free survival (DFS), and local and distant recurrence in patients with AL following low anterior resection. METHODS: This is an extension of a multicentre RCT (NCT01110798). Kaplan-Meier method and the log-rank test were used to estimate and compare the 3-, 5-, and 10-year OS and DFS, and local and distant recurrence in patients with and without AL. Predictors of OS and DFS were evaluated using the Cox regression analysis as secondary aim. RESULTS: Follow-up was available for 311 patients. Of them, 252 (81.0%) underwent neoadjuvant chemoradiotherapy and 138 (44.3%) adjuvant therapy. AL occurred in 63 (20.3%) patients. At a mean follow-up of 69.5 ± 31.9 months, 23 (7.4%) patients experienced local recurrence and 49 (15.8%) distant recurrence. The 3-, 5-, and 10-year OS and DFS were 89.2%, 85.3%, and 70.2%; and 80.7%, 75.1%, and 63.5% in patients with AL, and 88.9%, 79.8% and 72.3%; and 83.7, 74.2 and 62.8%, respectively in patients without (p = 0.89 and p = 0.84, respectively). At multivariable analysis, AL was not an independent predictor of OS (HR 0.65, 95%CI 0.34-1.28) and DFS (HR 0.70, 95%CI 0.39-1.25), whereas positive circumferential resection margins and pathological stage impaired both. CONCLUSIONS: In the context of modern multimodal rectal cancer treatment, AL does not affect long-term OS, DFS, and local and distant recurrence in patients with mid-low rectal cancer.

Crohn's Disease-Related Stoma Complications and Their Impact on Postsurgical Course.

INTRODUCTION: Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract. The diversion through a colostomy or an ileostomy is sometimes required for disease control. In these patients, common stoma-related complications sum up with CD-related complications and often require revisional surgery. METHODS: The aim of the study was to assess stoma morbidity after surgery for CD and to identify the burden of CD-related or CD-associated complications. Thus, details of past medical history, surgery, and follow-up of 54 consecutive patients operated on for CD with any sort of stoma were retrieved from the stoma therapist prospectively maintained database. RESULTS: In our series, 23 patients had a colostomy, and 31 patients had an ileostomy. Complications occurred after stoma creation in 38 patients (70%) at a median of 1.3 months (interquartile range 0.6-7.2). CD-related complications arose in 8 patients (including pyoderma gangrenosum in 3 patients, peristomal fistulae in 2, granulomas in 2, and peristomal abscess in 1). Patients with CD-related complications tended to have a shorter disease duration (p = 0.07) and higher occurrence of CD-related complications was associated with end-stoma (p = 0.006). In this cohort, 11 cases had to be surgically treated for peristomal fistulae or abscess, parastomal hernia, prolapse, pyoderma gangrenosum, and recurrent CD. DISCUSSION/CONCLUSIONS: In patients with CD, stoma creation is burdened by a high rate of postoperative complication and a relevant rate is specifically related to CD. Often these patients are required to be reoperated on to redo the stoma. Moreover, end-stoma configuration and aggressive CD phenotype are associated to a higher rate of complications.

Metachronous colorectal cancer have a similar microsatellite instability frequency but a lower infiltration of lymphomononuclear cells than primary lesions.

BACKGROUND: An increased risk of metachronous colorectal cancer is usually associated with microsatellite instability occurring in Lynch syndrome. However, not all patients with metachronous colorectal cancer have microsatellite instability. The density of tumor-infiltrating lymphocytes is an independent predictor of outcome in patients with colorectal cancer, and a fascinating hypothesis is that they can be involved in the onset of metachronous colorectal cancer. The aim of this study was to analyze the tumor microenvironment and tumor mutation frequency in sporadic and metachronous colorectal cancer. METHODS: The clinical and pathological records of a series of consecutive colorectal cancer patients who were operated on from 2015 to 2019 were retrieved for this retrospective study. We defined metachronous colorectal cancer as a second colorectal cancer that appeared at least 1 year after the primary one, and sporadic colorectal cancer as those that did not have a metachronous colorectal cancer. Histology for the infiltration of intratumoral lymphomononuclear cells, immunohistochemistry for MLH1, PMS2, MSH2, and MSH6, and mutational analysis of BRAF, KRAS, and NRAS were all performed. Sporadic colorectal cancer and metachronous colorectal cancer were compared. Nonparametric tests were used for small sample size comparison. RESULTS: In the study, 238 patients were operated on for colorectal cancer at the General Surgery Unit of the Azienda Ospedaliera di Padova from 2015 to 2019. We identified 26 patients with metachronous colorectal cancer, and only 3 of them had had adjuvant therapy after the primary colorectal cancer. No difference was observed in terms of cancer stage between metachronous and sporadic colorectal cancer. Mismatch repair gene deficiencies and microsatellite instability frequency was similar in metachronous colorectal cancer and in sporadic colorectal cancer (P = .77). Likewise, the mutation frequency of BRAF and KRAs was similar in the 2 groups (P = .75 and P = .21, respectively). To the contrary, the absence of infiltration of lymphomononuclear cells within the tumor (P = .004) in patients with metachronous colorectal cancer was more frequent and they tended to have a higher frequency of NRAS mutation (P = .06). CONCLUSION: Our study showed that, rather unexpectedly, microsatellite instability frequency was similar in metachronous and sporadic colorectal cancer. Moreover, our data suggest that an altered immune microenvironment may be a crucial factor, permitting the occurrence of metachronous colorectal cancer. In fact, the absence of lymphomononuclear cells can be the substrate for a weak immune response to cancer neoantigens, opening the way to a second primary colorectal cancer.

Prognostic significance of pathological sub-classification of pT3 rectal cancer.

PURPOSE: Patients with pT3 rectal cancer represent a heterogeneous prognostic group. A more accurate histological sub-classification of pT status has been suggested as an improvement of the TNM staging system. The aim of the study was to evaluate the prognostic implication of a histopathologic sub-classification of pT3 rectal cancer. METHODS: In this retrospective single-center study, pT3 rectal cancer patients who underwent surgery from January 2000 to December 2018 were evaluated. The maximum depth of tumor invasion beyond the muscularis propria was recorded. A ROC curve identified the best prognostic cutoff value to classify patients in two prognostic groups. Survival curves were estimated by the Kaplan-Meier method, and univariate and multivariate analyses with the Cox regression model were used to find independent factors influencing survival. RESULTS: Overall, 203 patients were included. Four millimeters was identified as the best cutoff value: 82 patients showed a depth of invasion < 4 mm (group A) and 121 ≥ 4 mm (group B). Both the estimated 5-year OS and DFS were statistically better in group A than in group B (OS: 83.9% vs 62.2%, p < 0.01; DFS: 78.3% vs 40.6%, p < 0.01). The depth of tumor invasion was an independent risk factor for OS (HR 2.25, 95% CI 1.26-3.99, p = 0.006) and DFS (HR 2.30, 95% CI 1.40-3.78, p = 0.001). CONCLUSION: Our findings suggest that a sub-classification of pT3 rectal cancer, based on the depth of tumor invasion, should be considered to be introduced in the TNM staging system.

MLH1 Deficiency Down-Regulates TLR4 Expression in Sporadic Colorectal Cancer.

Patients with mismatch repair (MMR)-deficient colorectal cancer (CRC) have a more favorable prognosis than patients with tumors with intact MMR. In order to obtain further insights on the reasons for this different outcome, we investigated the interplay between MMR genes and TLR4/MyD88 signaling. The cancer genome atlas (TCGA) databases were selected to predict the differential expression of TLR4 in colon cancer and its correlation with MMR genes. Moreover, the expression of MMR genes and TLR4 was evaluated by immunohistochemistry in 113 CRC samples and a cohort of 63 patients was used to assess TLR4 mRNA expression and MLH1 epigenetic silencing status. In vitro, the effect of MLH1 knockdown on TLR4 expression was quantified by Real Time PCR. TLR4 expression resulted dependent on MMR status and directly correlated to MLH1 expression. In vitro, MLH1 silencing decreased TLR4 expression. These observations may reflect the better prognosis and the chemoresistance of patients with CRC and MMR defects.

Impact on Quality of Life of Seton Placing in Perianal Crohn's Disease.

INTRODUCTION: Often, in perineal Crohn's disease (CD), a seton is placed to guarantee a constant drainage and prevent septic complication while biologic therapy is ongoing. This study aimed to assess the long-term quality of life after surgery for perineal CD in relation to seton placing. PATIENTS AND METHODS: Data of 65 consecutive patients with CD and non-CD operated on from 2014 to 2019 for perianal fistula or abscess were retrieved. Forty-three had CD and 14 of them had a seton placed during surgery and they kept it on while they had anti-TNF-alpha therapy. Patients were interviewed with the Cleveland Global Quality of Life (CGQL) and SF-12 quality of life questionnaires. Disease activity was defined as Harvey-Bradshaw Index (HBI) and Perianal Disease Activity Index (PDAI). Comparisons between groups were carried out with the nonparametric tests, and multiple regression models were used to assess predictors of quality of life. RESULTS: The total CGQL score and SF-12 mental component score (MCS) were significantly higher (and thus better) in the seton group than in patients treated without seton. On the contrary, SF-12 physical component score (PCS) was not different between the two groups. HBI was significantly better in patients in the seton group. At multivariate analysis, seton placement and HBI were confirmed to be independent predictors of long-term SF-12 MCS whereas only HBI confirmed to be a predictor of total CGQL score. CONCLUSIONS: Seton placing during anti-TNF-alpha therapy is independently associated with a better MCS. Unexpectedly, this device, instead of to cause psychological distress, seems to assure patients during their biologic therapy providing psychological benefit beyond the mere medical effect.

Can Vascular Endothelial Growth Factors and CD34 Expression Implement NICE (Narrow-Band Imaging International Colorectal Endoscopic) Classification in Colorectal Polypoid Lesion Diagnosis?

BACKGROUND: Vascular endothelial growth factor (VEGF) is a subfamily of growth factors involved in angiogenesis; CD34+ cells are normally found in endothelial progenitor cells and endothelial cells of blood vessels. Colonic adenomatous polyps may not always be completely removable endoscopically, and a preoperative diagnosis might still be necessary. The aim of the study was to evaluate whether VEGF-A, VEGF-C and CD34 mRNA expression along colorectal carcinogenesis steps can implement NICE (Narrow-Band Imaging International Colorectal Endoscopic) classification in the diagnosis of malignancy in colorectal polypoid lesions. METHODS: Seventy-one subjects with colonic adenoma or cancer who underwent screening narrow-band imaging (NBI) colonoscopy were prospectively enrolled in the MICCE1 project (Treviso center). Polyps were classified according to the NICE classification. Real-time RT-PCR for VEGF-A, VEGF-C and CD34 mRNA expression was performed. Nonparametric statistics, receiver-operating characteristic curve analysis and logistic multiple regression analysis were used. RESULTS: VEGF-A and CD34 mRNA expression was significantly higher in sessile adenomas than in polypoid ones (p < 0.001 and p = 0.01, respectively). VEGF-A, VEGF-C and CD34 mRNA expression was significantly higher in adenocarcinoma than in adenoma (p = 0.01, p = 0.01 and p = 0.01, respectively). The accuracy of VEGF-A, VEGF-C and CD34 mRNA expression for prediction of malignancy was 0.79 (95% CI 0.65-0.90), 0.81 (95% CI 0.66-0.91) and 0.80 (95% CI 0.65-0.90), respectively, while the accuracy of the NICE classification was 0.85 (95% CI 0.72-0.94). The determination coefficient R2, which indicates the amount of the variability explained by a regression model, for NICE classification alone was 0.24 (p < 0.001). A regression model that included NICE classification and VEGF-C mRNA expression showed an R2 = 0.39 as well as a model including NICE classification and CD34 mRNA levels. CONCLUSIONS: This study demonstrated that VEGF-C and CD34 mRNA levels might be useful to stratify colorectal polyps in different risk of progression classes by implementing the accuracy of the NICE classification. Studies on in vivo detection of these markers are warranted.

Laparoscopic Ventral Rectopexy for Obstructed Defecation: Functional Results and Quality of Life.

BACKGROUND: Laparoscopic ventral mesh rectopexy (LVR) is gaining wider acceptance as the preferred procedure to correct internal and external rectal prolapse with obstructed defecation syndrome (ODS) and/or fecal incontinence. The aim of our study was to analyze functional outcome and quality of life (Health-Related Quality of Life) after LVR for symptomatic internal prolapse and/or rectocele with ODS. METHODS: Prospectively collected data on LVR for internal rectal prolapse were analyzed in 50 consecutive female patients operated between January 2011 and December 2018. In all cases, we performed a LVR according to the D'Hoore technique. Patients had ODS and internal rectal prolapse (grade 3 or 4) confirmed at the defecogram study. We registered only 1 major complication that required surgical treatment (Clavien-Dindo IIIb). The median hospital stay was 4 days [interquartile range (IQR): 2 to 5 d]. Functional results were measured with the Wexner Constipation Score and the 36-Item Short-Form Health Survey, and were analyzed before surgery and after 3, 6, or 12 months. RESULTS: After a median follow-up of 16.5 months (IQR: 10 to 44.25 mo), the Wexner Total Score was significantly improved in almost all items passing from 14 (IQR: 11 to 18) to 11 (IQR: 6.25 to 14.75) after surgery (P<0.0001). Incontinence was cured in 8 of 11 patients (P=0.036). Compared with the preoperative score, the 36-Item Short-Form Health Survey score improved, especially for physical activity, varying from 75 to 87.5 (P=0.0156). No worsening of continence status, constipation, or sexual function was observed. CONCLUSION: LVR appears to provide a sustained improvement in Health-Related Quality of Life, constipation, and incontinence in patients with ODS without worsening constipation with low morbidity and recurrence.

Interferon-Gamma and Tumor Necrosis Factor-Related Weak Inducer of Apoptosis Expression in Neoangiogenesis in Colorectal Polypoid Lesions.

BACKGROUND: Interferon gamma (IFNγ) and tumor necrosis factor-related weak inducer of apoptosis (TWEAK) molecules seem to have a potential effect on angiogenic factors such as vascular endothelial growth factor (VEGF). The aim of this study was to assess a possible interplay between IFNγ and TWEAK cytokines and VEGF machinery in the different steps of colorectal carcinogenesis. METHODS: A total of 92 subjects with colonic adenoma or cancer who underwent screening colonoscopy or surgery were prospectively enrolled. Polypoid lesion tissue samples were collected and frozen. Real-time reverse transcription polymerase chain reaction for IFNγ, TWEAK, and VEGF-A mRNA expression was performed. Immunoassays for VEGF-A, VEGF-C, VEGFR-1, VEGFR-2, and VEGFR-3 were also performed. Nonparametric statistics, receiver operating characteristic curve analysis, and logistic multiple regression analysis were used. RESULTS: IFNγ and TWEAK mRNA expression was higher in patients with T2 or more advanced colorectal cancer than in those with adenomas or T1 cancer (p < 0.001 and p = 0.01, respectively). IFNγ and TWEAK mRNA expression levels directly correlated with VEGF-A mRNA expression levels (rho = 0.44, p < 0.001 and rho = 0.29, p = 0.004, respectively). On the contrary, IFNγ and TWEAK mRNA expression levels inversely correlated with VEGF-C protein levels (rho = -0.29, p = 0.04 and rho = -0.31, p = 0.03, respectively). Similarly, IFNγ and TWEAK mRNA expression levels inversely correlated with VEGFR2 protein levels (rho = -0.38, p = 0.033 and rho = -0.40, p = 0.025, respectively). CONCLUSION: This study showed that in colorectal polypoid lesions, IFNγ and TWEAK expressions are directly correlated to VEGF-A expression but inversely correlated with VEGFR2 levels, suggesting a possible feedback mechanism in the regulation of VEGF-A expression.