Surgical Outcomes in Splenic Flexure Cancers: A Multicenter Comparison of Segmental vs. Extended Hemicolectomy (SPARROW Study)

Overview

SPARROW Study: Surgical Outcomes in Splenic Flexure Cancer Colonic cancers located at the splenic flexure where the transverse colon turns into the descending colon are uncommon and represent less than 10% of all colorectal cancers. Because of their unique location between the blood supply of the right and left colon, there is no clear agreement on which surgical method provides the best results. Two main procedures are used: Segmental hemicolectomy, which removes only the part of the colon containing the tumor, and Extended hemicolectomy, which removes a larger section of the colon and more lymph nodes. The SPARROW Study is a prospective, multicenter observational study designed to compare these two surgical approaches in patients with splenic flexure cancer. The study will include about 140 patients (70 in each group) from multiple tertiary colorectal centers in Turkey and Europe. Researchers will collect information about each patient's surgery, recovery, and follow-up outcomes. The main outcomes include postoperative ileus, leakage at the surgical connection (anastomosis), wound infection, and total postoperative complications. Other outcomes include number of lymph nodes removed, complete tumor resection (R0), hospital stay, recovery time, reoperation, and 3-year overall and disease-free survival. By analyzing both short- and long-term results, the SPARROW Study aims to provide high-quality evidence to guide surgeons in choosing the best and safest operation for patients with splenic flexure cancers. All participants will provide written informed consent before joining the study. The study has received ethical approval from the Koç University Ethics Committee and will be conducted in accordance with the Declaration of Helsinki.

Study Rationale: Splenic flexure cancers pose unique surgical challenges due to their variable blood supply and lymphatic drainage. The optimal extent of resection remains controversial, with both extended right and left colectomy approaches showing different technical advantages. However, there are no prospective multicenter data comparing their perioperative and oncologic outcomes. Study Design: This is a prospective, multicenter observational cohort study involving tertiary colorectal cancer centers. The study will enroll 140 consecutive adult patients (≥18 years old) undergoing elective curative resection for histologically confirmed splenic flexure adenocarcinoma. Surgical approach-segmental or extended colectomy-will be chosen according to the operating surgeon's routine practice and preference, not assigned by randomization. Primary Outcomes: Postoperative ileus (incidence and duration) Anastomotic leakage Wound infection Total postoperative complications Secondary Outcomes: Lymph node yield and R0 resection rate Postoperative mortality Operation time and estimated blood loss Hospital stay, return to regular diet, and time to first flatus Reoperation rates 3-year overall survival (OS) and disease-free survival (DFS) Timeline: Study start: 2025 Enrollment period: 24 months Follow-up: 36 months per patient Total duration: approximately 5 years Ethical Conduct: Ethical approval was obtained from the Koç University Ethics Committee. Each participating center will obtain local ethics approval. The study adheres to the principles of the Declaration of Helsinki and Good Clinical Practice (GCP). Expected Impact: This will be the first prospective multicenter observational study to compare segmental and extended hemicolectomy for splenic flexure cancers. The results will help standardize surgical decision-making and improve patient outcomes for this uncommon and technically challenging tumor location.