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

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.

Inclusion criteria

• Adult patients aged 18 years or older
• Histologically confirmed adenocarcinoma of the splenic flexure
• Elective surgical resection performed with curative intent (segmental colectomy or extended hemicolectomy)
• Availability of complete perioperative and follow-up data
• Written informed consent provided prior to participation
• Surgery performed by colorectal or general surgeons meeting institutional eligibility criteria (≥20 colorectal cancer cases/year, ≥2 years of colorectal training)

Exclusion criteria

• Emergency surgery for obstruction, perforation, or bleeding
• Non-adenocarcinoma histology (e.g., lymphoma, neuroendocrine tumor, gastrointestinal stromal tumor)
• Patients undergoing palliative resections, local excisions, or bypass procedures without curative intent
• Presence of synchronous colorectal malignancy or distant metastasis requiring simultaneous resection
• Previous colorectal resection involving the splenic flexure
• Patients with incomplete clinical or pathological data or those lost to follow-up before 30 days postoperatively