Introduction
Bladder cancer (BC) is the eleventh most diagnosed cancer in both sexes. The worldwide age-standardized incidence rate is 9.0 cases per 100,000 per year for men and 2.2 for women 1. Approximately 75% of patients diagnosed with BC have mucosal disease and 15-25% have muscle invasive BC 2. EAU Guidelines report that radical cystectomy (RC) is the standard treatment for localized MIBC and suggests for non-invasive tumors with the highest risk of progression1.
Complications related to RC may be directly related to surgery, intestinal anastomosis or urinary diversion, other than previously existing comorbidity 3. Early complications such as perioperative blood transfusion and gastrointestinal complications occur in 55–78% and major complications in 32% of the patients4. Late complications include urinary tract infection, kidney dysfunction, stone formation, metabolic complications, and relapse of the disease. Peri-operative mortality for RC and urinary diversion was reported as 2.3-8.0% at 90 days 1. Increased BMI, High American Society of Anesthesiologists (ASA) score, bleeding, and Charlson Comorbidity Index (CCI) are among the known causes of perioperative complications 5. Patients undergoing RC for BC, the 5-year recurrence-free survival (RFS) rate was 58%, cancer-specific survival (CSS) was 66% and overall survival (OS) was 66% 6,7. Some of the most significant predictors of OS of RC with urinary diversion are age, ASA, smoking habits, stage, grade, nodal status, neoadjuvant chemotherapy, general condition status and delay from the first symptoms to surgery 8.
The effect of body mass index (BMI) on oncological and surgical outcomes of RC with urinary diversion is controversial. A number of studies examining the role of BMI in patients with BC report that high BMI is associated with a high risk of BC development and disease recurrence, negatively affecting cancer-specific mortality and surgical morbidity2,9,10. However, conflicting findings have also been reported which showed that BMI does not affect disease-specific survival after RC, and the complication, transfusion rates, and length of hospital stay are similar 11-14. In this multicenter study, we tried to evaluate the effect of increased BMI on surgical and oncological outcomes of BC patients treated with RC, using the BC database of the Urooncology Association, Turkey