The goal of this clinical trial is to assess the safety and efficacy of Human Placenta Mesenchymal Stem Cells Derived Exosomes in preventing early anastomosis leak in patients undergoing low anterior resection for rectal cancer. The main question it aims to answer are

Do Mesenchymal Stem Cell-Derived Exosomes prevent early anastomosis leak in patients undergoing low anterior resection for rectal cancer?

If there is a comparison group: Researchers will compare Mesenchymal Stem Cells Derived Exosomes to placebo to see if it can prevent early anastomotic leakage.

Participants will receive intraperitoneal Mesenchymal Stem Cells Derived Exosomes at the end of their surgery.

Anastomotic leakage remains one of the most severe complications following colorectal surgery, leading to increased morbidity, prolonged hospitalization, and reduced quality of life. Despite advances in surgical techniques and perioperative care, the incidence of early anastomotic leaks persists. Practical strategies to reduce this risk are crucial for improving patient outcomes.

Recent studies have highlighted the potential role of mesenchymal stem cell-derived exosomes in enhancing tissue repair and modulating inflammation. These extracellular vesicles, derived from human placenta mesenchymal stem cells (hPMSC), contain bioactive molecules such as proteins, lipids, and RNA that facilitate cellular communication and promote healing processes. Preclinical research suggests that exosomes can support anastomotic healing by reducing local inflammation.

This study aims to evaluate the safety and efficacy of intraperitoneal administration of hPMSC-derived exosomes in preventing early anastomotic leakage in patients undergoing low anterior resection (LAR) for rectal cancer. We hypothesize that the exosome treatment will significantly reduce the incidence of anastomotic leaks compared to placebo, thereby improving postoperative recovery and reducing hospital stay.

Inclusion Criteria:

-Patients with Stage II-III rectal cancer who underwent neoadjuvant chemoradiation therapy and are candidates for low anterior resection surgery

Exclusion Criteria:

• Patients who need emergency surgery (presenting with peritonitis or signs of obstruction)
• Patients with apparent malnutrition or patients who have serum albumin levels of less than 3 g/dl
• Patients who receive corticosteroids ( an equivalent dose of prednisolone 5 mg/day or more)
• Patients with chronic pulmonary disease
• Patients who need more than two units of blood transfusion perioperatively