Parietal complications after cystectomy: Incisional and parastomal hernia, epidemiology and risk factors.

INTRODUCTION: Incisional and parastomal hernias are frequent complications after cystectomy. The aim of our study was to define their incidence, identify risk factors related to the patient and the surgical technique, and identify means of prevention. MATERIAL: This was a multicenter, retrospective study, analyzing clinical and radiological data from 521 patients operated on for cystectomy between January 2010 and December 2020. RESULTS: In total, 521 patients, 471 men and 50 women, mean age 68.8years, were included. Thirty-one patients (6.6%) presented with an evisceration. Risk factors were a history of evisceration (OR: 14.1; 95% CI: [3-66]; P=0.0008), COPD (OR: 3.5; 95% CI: [1.3-9 .4]; P=0.0119), ischemic heart disease (OR: 4; 95% CI: [1. 6-10]; P=0.0036), and split-stitch closure (OR: 3.1; 95% CI: [1.065-8.9]; P=0.0493). Fifty-one patients (9.9%) presented with an incisional hernia. Risk factors were a history of COPD (OR: 4, 95% CI: [2.1-7.6]; P<0.001) and postoperative pulmonary infection (OR: 5.3; 95% CI: [1.05-26.4]; P=0.0079). Seventy-nine patients (15.28%) had a parastomal hernia. Overweight was a risk factor (OR: 2.3; 95% CI: [1.3-4.5]; P=0.0073). CONCLUSION: Patients who are overweight or have pulmonary comorbidities are at greater risk of developing parietal complications after cystectomy. LEVEL OF EVIDENCE: III.

Cohort profile: COBLAnCE: a French prospective cohort to study prognostic and predictive factors in bladder cancer and to generate real-world data on treatment patterns, resource use and quality of life.

PURPOSE: Bladder cancer is a complex disease with a wide range of outcomes. Clinicopathological factors only partially explain the variability between patients in prognosis and treatment response. There is a need for large cohorts collecting extensive data and biological samples to: (1) investigate gene-environment interactions, pathological/molecular classification and biomarker discovery; and (2) describe treatment patterns, outcomes, resource use and quality of life in a real-world setting. PARTICIPANTS: COBLAnCE (COhort to study BLAdder CancEr) is a French national prospective cohort of patients with bladder cancer recruited between 2012 and 2018 and followed for 6 years. Data on patient and tumour characteristics, treatments, outcomes and biological samples are collected at enrolment and during the follow-up. FINDINGS TO DATE: We describe the cohort at enrolment according to baseline surgery and tumour type. In total, 1800 patients were included: 1114 patients with non-muscle-invasive bladder cancer (NMIBC) and 76 patients with muscle-invasive bladder cancer (MIBC) had transurethral resection of a bladder tumour without cystectomy, and 610 patients with NMIBC or MIBC underwent cystectomy. Most patients had a solitary lesion (56.3%) without basement membrane invasion (71.7% of Ta and/or Tis). Half of the patients with cystectomy were stage ≤T2 and 60% had non-continent diversion. Surgery included local (n=298) or super-extended lymph node dissections (n=11) and prostate removal (n=492). Among women, 16.5% underwent cystectomy and 81.4% anterior pelvectomy. FUTURE PLANS: COBLAnCE will be used for long-term studies of bladder cancer with focus on clinicopathological factors and molecular markers. It will lead to a much-needed improvement in the understanding of the disease. The cohort provides valuable real-world data, enabling researchers to study various research questions, assess routine medical practices and guide medical decision-making.