The Impact of Neoadjuvant Therapy on Perioperative Complications and Treatment Outcomes in Patients Undergoing Colorectal Cancer Resection

The study hypothesis is that neoadjuvant therapy of colorectal cancer leads to endothelial dysfunction, reduced microvascular density, and tissue fibrosis, and therefore contributes to the occurrence of perioperative complications. The primary objective of the study is to assess the association between microvascular density and neoadjuvant therapy, identify differences in biomarkers and demographic factors between patients with neoadjuvant therapy and those without neoadjuvant therapy, and compare clinical outcomes between patients treated with neoadjuvant therapy and those who underwent surgery as initial treatment. Secondary objectives are to determine the association of microvascular density and fibrosis in surgical wound tissue with postoperative complications and wound healing complications, and identify differences in biomarkers between patients with and without perioperative complications.

The study was approved by the Ethics Committee of the Osijek Clinical Hospital Center.

The study will include 34 consecutive patients undergoing colorectal cancer surgery who received neoadjuvant therapy and 34 patients undergoing colorectal cancer surgery who did not receive neoadjuvant therapy but whose first-line treatment is surgery. During the surgery, a skin and subcutaneous tissue sample will be taken for pathohistological analysis of microvascular density and tissue fibrosis, allowing for a more detailed assessment of microvascular changes associated with perioperative complications. It is planned to follow the patient from the surgery until the end of hospitalization, and data on post-discharge complications will be tracked through the medical history in the Hospital Information System one month after discharge from the hospital.