Risk Factors of Anastomotic Leakage After Anterior Resection for Rectal Cancer Patients.

OBJECTIVE: Anastomotic leakage (AL) is one of the serious complications after anterior resection for rectal cancer. Defunctioning stoma (DS) is one of the most widely used approaches to prevent it; however, the effect of DS on the occurrence of AL remains controversial. This study aimed to investigate risk factors of AL and assess the effect of DS after anterior resection for rectal cancer patients. METHODS: A retrospective analysis was conducted for the data of 1840 patients who underwent anterior resection for rectal cancer from January 2014 to December 2019. RESULTS: The results showed the overall AL incidence was 7.5%. Multivariate analyses revealed that males [odds ratio (OR) 1.562] and T3-T4 stage (OR 1.729) were independent risk factors for all patients. After propensity score matching analysis, the AL incidence was 14.1% in the group with no DS and 6.4% in the DS group (P<0.001). The clinical AL (grade B + grade C) incidence was 12.4% in no DS group and 4.6% in the DS group (P<0.001). CONCLUSION: The study suggested that males and T3-T4 stage were independent risk factors of AL. In addition, DS could reduce the rate of symptomatic AL.

Acidity-Triggered Tumor Retention/Internalization of Chimeric Peptide for Enhanced Photodynamic Therapy and Real-Time Monitoring of Therapeutic Effects.

Photodynamic therapy (PDT) holds great promise in tumor treatment. Nevertheless, it remains highly desirable to develop easy-to-fabricated PDT systems with improved tumor accumulation/internalization and timely therapeutic feedback. Here, we report a tumor-acidity-responsive chimeric peptide for enhanced PDT and noninvasive real-time apoptosis imaging. Both in vitro and in vivo studies revealed that a tumor mildly acidic microenvironment could trigger rapid protonation of carboxylate anions in chimeric peptide, which led to increased ζ potential, improved hydrophobicity, controlled size enlargement, and precise morphology switching from sphere to spherocylinder shape of the chimeric peptide. All of these factors realized superfast accumulation and prolonged retention in the tumor region, selective cellular internalization, and enhanced PDT against the tumor. Meanwhile, this chimeric peptide could further generate reactive oxygen species and initiate cell apoptosis during PDT. The subsequent formation of caspase-3 enzyme hydrolyzed the chimeric peptide, achieving a high signal/noise ratio and timely fluorescence feedback. Importantly, direct utilization of the acidity responsiveness of a biofunctional Asp-Glu-Val-Asp-Gly (DEVDG, caspase-3 enzyme substrate) peptide sequence dramatically simplified the preparation and increased the performance of the chimeric peptide furthest.