Lymphovascular Invasion of Urothelial Cancer in Matched Transurethral Bladder Tumor Resection and Radical Cystectomy Specimens

Abstract

Lymphovascular invasion is an independent predictor of nodal invasion and survival in patients undergoing radical cystectomy. When assessed in transurethral bladder tumor resection specimens, lymphovascular invasion could predict tumor behavior and guide treatment decisions. However, the reliability of assessing lymphovascular invasion in such specimens has not been systematically evaluated. We examined the agreement of lymphovascular invasion status in matched transurethral bladder tumor resection and cystectomy specimens. A retrospective analysis was performed of patients undergoing transurethral bladder tumor resection within 6 weeks of cystectomy. Tumor stage and lymphovascular invasion status were assessed in transurethral bladder tumor resection specimens and compared to those in corresponding cystectomy specimens. Agreement of lymphovascular invasion status was determined using McNemar's test. A total of 75 patients were eligible for study. In transurethral bladder tumor resection specimens lymphovascular invasion was identified in 17 patients (23%), including 2 (8%) in the T1 and 15 (30%) in the T2 or greater groups. In matched cystectomy specimens lymphovascular invasion was identified in 30 patients (40%), including 9 (36%) in the T1 and 21 (42%) in the T2 or greater populations. A lack of lymphovascular invasion agreement was observed between transurethral bladder tumor resection and cystectomy specimens in the entire population and in patients with cT1 tumors (p = 0.009 and 0.02, respectively). However, good concordance was seen in patients with muscle invasive disease (p = 0.13). Nodal metastasis was observed in 7 of 17 patients (41%) with detectable lymphovascular invasion in the transurethral bladder tumor resection specimen. When lymphovascular invasion is identified in a transurethral bladder tumor resection sample, it will be present in the cystectomy sample in 65% of cases and associated with nodal metastasis in 41%. Lymphovascular invasion is a valuable histological tool in the evaluation of transurethral bladder tumor resection samples, particularly cT2 tumors, because there is significant agreement of lymphovascular invasion status at transurethral bladder tumor resection and at subsequent cystectomy.