Colorectal resections - clinical and immunological results

INTRODUCTION: Surgery induces a generalized state of postoperative immunosuppression responsible for a lot of complications in postoperative period. Magnitude and type of the intraoperative injury depend on the extent and duration of postoperative immune suppression. This study compared clinical outcomes and immune changes after minimally invasive and open colorectal resections in patients with colorectal cancer (CRC).MATERIAL AND METHODS: Study included 40 patients with CRC who underwent colorectal resections in our clinic last year. Twenty one of them underwent minimally invasive surgery, with a mean age of 64.8 years (49-86). The rest 19 patients underwent conventional surgery, with a mean age of 66.2 years (56-84). Blood tests were performed 24 hours prior to surgery, 24 hours and 7 days after surgery. Analysis included full blood count, total protein, albumin and markers of inflammation (CRP, ESR, fibrinogen). T- (CD3+), B- (CD19+) and NK-cell lymphocyte populations were studied by means of flow cytometry, as well as activation of leucocytes, according to the expression of HLA-DR, CD38, CD279, CD163 and some clinical parameters. All data were analyzed using SPSS version 21.RESULTS: There was no significant difference in preoperative results between minimally invasive group and conventional group. At 24 hours after surgery there were significant decrease in lymphocyte percentages and increased leucocyte count, granulocyte percentages and CRP levels in conventional group. This ratio maintained at 7 days after surgery. Activated monocyte (CD 163+), total protein and albumin, eosinophiles, percentage of monocytes, lymphocytes and NKT-cells (CD3+ CD16/CD56+) were significant decrease in conventional group compared with minimally invasive group at first postoperative day.CONCLUSIONS: Minimally invasive colorectal cancer resection is a technically feasible option, with comparable results in terms of oncologic clearance, lesser degrees of tissue injury, surgical metabolic stress, and immunosuppressive response to conventional open surgery. Patients undergoing minimally invasive resections demonstrated improved clinical recovery and shorter hospital stay than patients undergoing open surgery. 

Predictive Factors and Risk Model for Positive Circumferential Resection Margin Rate after Transanal Total Mesorectal Excision in 2653 Patients with Rectal Cancer

The aim of this study was to determine the incidence of, and preoperative risk factors for, positive circumferential resection margin (CRM) after transanal total mesorectal excision (TaTME). Background: TaTME has the potential to further reduce the rate of positive CRM for patients with low rectal cancer, thereby improving oncological outcome. Methods: A prospective registry-based study including all cases recorded on the international TaTME registry between July 2014 and January 2018 was performed. Endpoints were the incidence of, and predictive factors for, positive CRM. Univariate and multivariate logistic regressions were performed, and factors for positive CRM were then assessed by formulating a predictive model. Results: In total, 2653 patients undergoing TaTME for rectal cancer were included. The incidence of positive CRM was 107 (4.0%). In multivariate logistic regression analysis, a positive CRM after TaTME was significantly associated with tumors located up to 1 cm from the anorectal junction, anterior tumors, cT4 tumors, extra-mural venous invasion (EMVI), and threatened or involved CRM on baseline MRI (odds ratios 2.09, 1.66, 1.93, 1.94, and 1.72, respectively). The predictive model showed adequate discrimination (area under the receiver-operating characteristic curve >0.70), and predicted a 28% risk of positive CRM if all risk factors were present. Conclusion: Five preoperative tumor-related characteristics had an adverse effect on CRM involvement after TaTME. The predicted risk of positive CRM after TaTME for a specific patient can be calculated preoperatively with the proposed model and may help guide patient selection for optimal treatment and enhance a tailored treatment approach to further optimize oncological outcomes