Laparoscopic Versus Open Surgery for Colon Cancer With Visceral Obesity

Study on Surgical Approaches for Colon Cancer Patients with Visceral Obesity

Colorectal cancer stands as a major malignant tumor threatening human health. Laparoscopic surgery has been widely adopted in colon cancer treatment, as it yields comparable survival outcomes to open surgery while offering the advantage of minimal invasiveness. However, with the global escalation of obesity, laparoscopic intervention becomes increasingly challenging in colon cancer patients with visceral obesity, potentially compromising surgical quality.

Notably, earlier landmark studies including COST, COLOR, and CLASICC have confirmed that laparoscopic surgery is non-inferior to open surgery in colon cancer patients. Nevertheless, these studies enrolled relatively lean patients with a Body Mass Index (BMI) below the average level of their respective regions; the COLOR study even excluded patients with a BMI exceeding 30 kg/m². Additionally, transverse colon cancer and splenic flexure colon cancer were excluded from these trials, rendering their data insufficiently representative of the growing population of obese colon cancer patients.

In contrast, the JCOG0404 study specifically demonstrated that colon cancer patients with a BMI ≥ 25 kg/m² had significantly poorer prognostic outcomes after laparoscopic surgery compared to open surgery. Further evidence from European waist-to-hip ratio studies and meta-analyses indicates that obese patients-especially those with abdominal obesity-pose greater surgical challenges. For such patients, laparoscopic surgery is associated with fewer harvested lymph nodes, higher conversion rates to open surgery, and potentially compromised surgical quality, which may ultimately lead to inferior long-term prognosis.

The Body Round Index (BRI), calculated using height and waist circumference, serves as a robust predictor of Visceral Fat Area (VFA). It exhibits superior performance to traditional anthropometric indicators such as BMI, waist circumference, and waist-to-hip ratio. Based on BRI and BMI data from Chinese and American populations, as well as clinical observations by the research team, patients with a BRI ≥ 5.0 present with significant visceral fat accumulation, which substantially increases the complexity of surgical procedures.

This study is designed as a prospective, international, multicenter, randomized, open-label, parallel-controlled trial to clarify whether open surgery is superior to laparoscopic surgery in terms of long-term outcomes for colon cancer patients with visceral obesity (defined as BRI ≥ 5.0). Eligible participants meeting all inclusion criteria will be enrolled and randomly assigned in a 1:1 ratio to either the laparoscopic surgery group or the open surgery group. Both groups will undergo surgery adhering to the Complete Mesocolic Excision (CME) standard. Postoperatively, patients will be followed up for 5 years in accordance with the predefined follow-up protocol. The primary outcome measure is the 3-year disease-free survival rate, while secondary outcomes include specimen quality, 30-day postoperative complications and mortality.

• Length of colon resected [Срок оценки: 2 weeks post operation.]
• Length of small bowel resected [Срок оценки: 2 weeks post operation.]
• Distance between tumor and closest arterial vascular division [Срок оценки: 2 weeks post operation.]
• Distance between nearest bowel wall and the same vascular division [Срок оценки: 2 weeks post operation.]
• Area of mesentery resected [Срок оценки: 2 weeks post operation.]
• Mesocolic grading [Срок оценки: 2 weeks post operation.]
• Number of lymph nodes harvested [Срок оценки: 2 weeks post operation.]
• Incidence of intraoperative complications [Срок оценки: From the start of surgical skin incision to the completion of skin suturing.]
• Incidence 30-day postoperative complications [Срок оценки: From the completion of skin suturing to 30 days after surgery.]