Clinical trials

This study hypothesizes that approximately 50% of rectal cancer patients can preserve their rectum using a watch-and-wait strategy if they achieve a complete or near-complete clinical response to total neoadjuvant therapy (TNT). The objective is to determine whether the complications, quality of life, and survival rates of rectal cancer patients who have achieved a complete or near-complete clinical response to TNT, followed by a watch-and-wait approach, are comparable to those of patients who undergo surgery first. Additionally, the study aims to identify potential prognostic and predictive markers for rectal cancer and examine survival rates and factors influencing responses to chemoradiotherapy (CRT) or TNT. The study is divided into two parts: \*\*Part One:\*\* Participants with cT1N1, T2-T3 N0-1 rectal cancer, MRF-, and EMVI-, with surgery as one of the possible first-line treatment options, will be randomized into two groups. The experimental group will consist of participants receiving TNT, including CRT and consolidation chemotherapy (Ch). If these participants achieve a complete or near-complete clinical response, they will be observed using a watch-and-wait strategy, which is a non-operative approach. The control group will consist of participants who undergo surgical treatment initially. \*\*Part Two:\*\* All participants with rectal cancer who have received CRT or TNT will be included. Additionally, participants diagnosed with rectal cancer who are scheduled for CRT or TNT but declined to participate in Part One or do not meet the inclusion criteria will also be included.

Infections remain a prevalent complication after major abdominal surgery. The common belief that most surgical site infections (SSIs) following elective surgery with modern antiseptic techniques are due to intraoperative contamination is still not confirmed. Therefore, alternative mechanisms for SSI development, such as the Trojan Horse theory-which suggests that pathogens from distant sites like the gastrointestinal tract may cause postoperative infections-should be explored. This study aims to analyze the preoperative microbiome of surgical patients' gut and oral cavities and assess whether microorganisms found there are present at the infection site. Additionally, this study will investigate a panel of biomarkers for predicting postoperative infections.