PurposeAn intestinal perforation is a rare condition, but has a high mortality rate, even after immediate surgical intervention. The clinical predictors of postoperative morbidity and mortality are still not well established, so this study attempted to identify risk factors for postoperative morbidity and mortality after surgery for an intestinal perforation.MethodsWe retrospectively analyzed the cases of 117 patients who underwent surgery for an intestinal perforation at a single institution in Korea from November 2008 to June 2014. Factors related with postoperative mortality at 1 month and other postoperative complications were investigated.ResultsThe mean age of enrolled patients was 66.0 ± 15.8 years and 66% of the patients were male. Fifteen patients (13%) died within 1 month after surgical treatment. Univariate analysis indicated that patient-related factors associated with mortality were low systolic and diastolic blood pressure, low serum albumin, low serum protein, low total cholesterol, and high blood urea nitrogen; the surgery-related factor associated with mortality was feculent ascites. Multivariate analysis using a logistic regression indicated that low systolic blood pressure and feculent ascites independently increased the risk for mortality; postoperative complications were more likely in both females and those with low estimated glomerular filtration rates and elevated serum C-reactive protein levels.ConclusionVarious factors were associated with postoperative clinical outcomes of patients with an intestinal perforation. Morbidity and mortality following an intestinal perforation were greater in patients with unstable initial vital signs, poor nutritional status, and feculent ascites.

Tumor grade combined with tumor size is an important predictive factor for lymph node metastasis and could serve as a prognostic factor for survival outcomes.

We report our experience in the use of transanal minimally invasive surgery (TAMIS) and the feasibility and safety of this surgical technique in operating for various rectal diseases that require a transanal approach. Methods: Between 2013 and 2019, 30 patients underwent TAMIS for a rectal lesion at Seoul National University Boramae Medical Center. The clinical data including age, gender, body mass index, tumour size, distance from the anal verge, diagnosis, operation time, postoperative complications, duration of hospital stay, and post-operative margin status were obtained retrospectively from the electronic medical records. Results: The mean operation time was 52.1±33.5 and the mean duration of hospital stay after surgery was 4.3±4.2 days. Most of the patients had undergone TAMIS for neuroendocrine tumor (NET) (60%) followed by an adenoma (16.7%) and rectal cancer (13.3%). 4 patients (13.3%) had minor complications after TAMIS. 2 patients (50%) had complained of diarrhea, 1 patient (25%) complained of fecal incontinence and 1 patient (25%) been diagnosed fluid in the operation bed. Conclusion: TAMIS is a useful method for local excision of rectal lesion located in mid to upper rectum as well as other rectal pathologies that require a transanal approach.

Background: Tumors grow in accordance with immunoediting. If we can see the changes of immune characteristics in the microenvironment during tumor growth, we can have much information of the mechanism of immunoediting. Peritoneal tumor cells from colorectal cancers are mostly derived from the shedding of tumor cells exposed on the visceral peritoneum. After the surgical removal of the primary tumors of which cells are exposed on the visceral peritoneum (T4 stage) but without macroscopic tumor seedings in the peritoneal cavity, some patients experience peritoneal recurrence but others do not. This implies that in the patients with future peritoneal recurrences the microscopic tumor cells in the peritoneal cavity have already been immunoedited. In addition, ascites and peritoneal immune cells are components of tumor microenvironment during peritoneal tumor growth if the peritoneal cavity is not contaminated by microorganisms by bowel perforation. And ascites and peritoneal cells are appropriate materials for immediate analysis after collection. Therefore, if we establish peritoneal immune characteristics of each T4 patient and compare those between the recurred and non-recurred patients in the peritoneal cavity afterwards, we can hold the clues of immunoediting during the peritoneal tumor growth. In this study we tested this autologous human growing tumor model for the relevance of research subject for cancer-associated immune response, as a pilot study. Method: Ascites and peritoneal cells were collected during the operation of colon cancer patients. If blood were mixed during the collection, the ascites and cells were discarded. The patients, whose ascites and peritoneal cells had been harvested, were classified into four groups (PC stages) according to the progression of peritoneal tumor growth on the basis of pathological report. SE-(serosa exposure negative; no tumor cells in peritoneal cavity) is a group of patients without exposure of cancer cells to peritoneal cavity (T3 or lower T stage). SE+(serosa exposure positive; microscopic tumor cells in peritoneal cavity) is a group of patients of T4 lesion without peritoneal seedings. l-PC represents localized peritoneal seedings which could be removed entirely during surgery. g-PC is a group of generalized peritoneal seeding. We performed ELISA and flow cytometry analysis as well as immune cell activation. Result: Of the 10 cytokines assayed in ascites, IL10, IL6 and TGF-beta increased according to the tumor progression in the peritoneal cavity, while the other cytokines (IL2, IL4, IL5, IL12, IL17, TNF and IFN-gamma) did not show any changes. Of the 42 SE+ patients, eleven experienced peritoneal recurrences. Mean IL10 (42 vs 24 pg/mL) and IL6 (2,092 vs 4472 pg/mL) levels of patients with peritoneal recurrence were higher than those without recurrence although we could not have significance (P = 0.113 and 0.180 each, Mann-Whitney U test). Activation of peritoneal cells by LPS increased IL6 as well as IL10 while activation by antiCD3 and antiCD28 did not. Intracellular IL10 was stained in T cells while IL6 in CD14 cells after LPS stimulation. Moreover, although ascitic IL6 increased up to tens of thousands pg/mL in g-PC patients, the blood level stayed at tens pg/mL. This means the ascites and peritoneal immune cells belong to a microenvironment which is seldom reflected in peripheral blood. Conclusion: This model showed the possibility of relevance to explore cancer-associated immune response in the tumor microenvironment during tumor growth in colorectal cancer. It is expected that further studies will provide much information of the mechanism of suppression of anti-tumor immune response. And the results derived from this model can help to extend understandings of immunoediting in primary tumors, metastatic tumors and, further, in other cancers. Citation Format: Seung Chul Heo, Sang Mok Lee, Beonghoon Sohn, Ji-Eun Kim, Rumi Shin. Autologous human growing tumor model and its immunological relevance for cancer immunology research [abstract]. In: Proceedings of the Second CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; 2016 Sept 25-28; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(11 Suppl):Abstract nr B140.