Pelvic lymph node dissection during radical cystectomy for muscle-invasive bladder cancer

Abstract

Radical cystectomy is the gold-standard treatment option for muscle-invasive and metastatic bladder cancer. At the time of cystectomy, up to 25% of patients harbour metastatic lymph node deposits. These deposits most frequently occur in the obturator fossa, but can be as proximal as the interaortocaval region. Thus, the use of concurrent pelvic lymph node dissection (PLND) with cystectomy has been increasingly reported. Data from studies including many patients suggest substantial oncological benefit in PLND cohorts versus non-PLND cohorts, irrespective of pathological nodal status. Additionally, PLND provides useful prognostic information, including disease burden, lymph node density, and extracapsular extension of metastatic lymph nodes. Accordingly, the National Comprehensive Cancer Network guidelines advocate the use of PLND during radical cystectomy for muscle-invasive bladder cancer. Despite this recommendation, a lack of consensus exists regarding the optimal PLND template. Comparative series suggest that extended PLND provides improved recurrence-free survival and cancer-specific survival compared with more limited PLND templates. More extensive templates (such as super-extended PLND) provide no additional survival benefit at the potential cost of increased operative time and patient morbidity. In addition to extended PLND templates, increased nodal harvest confers an oncological benefit in patients with node-positive disease or in patients with node-negative disease. Accordingly, recommendations for a minimum nodal yield have been proposed. Despite the growing body of evidence, formal recommendations by oncological and urological authoritative bodies have been limited owing to the lack of randomized data and level I evidence.