Perioperative Outcomes After Neoadjuvant Therapy in Colorectal Cancer

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

This prospective study investigates the effects of neoadjuvant therapy on endothelial function, microvascular tissue density, and tissue fibrosis in patients with colorectal cancer and their association with perioperative complications. The primary objective is to assess differences in microvascular tissue density between patients who received neoadjuvant therapy and those who did not, biomarkers, and demographic factors between patients who received neoadjuvant therapy and those who underwent surgery as initial treatment, and to compare clinical outcomes. The study will include 34 patients treated with neoadjuvant therapy and 34 patients for whom surgery is the first-line treatment. Patients will be followed until discharge from the hospital, and complications after discharge will be monitored through medical records one month after surgery.

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.

Inclusion Criteria:

• Adults aged ≥18 years with histologically confirmed colorectal cancer
• Planned surgical treatment for colorectal cancer (either laparoscopic LPSC or open laparotomy)
• Ability to understand the study protocol and provide written informed consent.
• Both sexes
• ASA classification II or III
• Patients who received neoadjuvant therapy is investigational group and patients who did not receive neoadjuvant therapy is control group

Exclusion Criteria:

• Age <18 years
• Patients who are not conscious, not oriented, or unable to provide informed consent
• Patients unable to understand the study protocol
• Emergency surgical cases
• Patients on chronic corticosteroid therapy