Detection and agreement of blood- and lymph vessel invasion assessed by immunohistochemistry in matched TURBT and radical cystectomy specimens

Vessel invasion (VI) in transurethral resection of bladder tumor (TURBT) usually assessed without immunohistochemistry (IHC) is associated with nodal metastases and reduced survival. Separation of blood (BVI) and lymph (LVI) vessel invasion by IHC in cystectomy (RC) suggests different prognostic trajectories and could guide management after TURBT. However, prevalence of BVI and LVI in TURBT and accuracy between TURBT and RC has not been thoroughly evaluated. We aimed to examine the prevalence of VI, BVI and LVI in TURBT using IHC, and investigate their agreement across matched TURBT and RC. We reviewed TURBT specimens from 244 patients later treated with RC with respect to VI on routine sections. On one selected block for each case D2-40/CD31 antibodies were applied. Accuracy of VI status was assessed comparing the corresponding RC results, and the differences across specimen types were assessed using McNemar´s test. In TURBT, more VI was detected with IHC (43 % vs. 31 %). The prevalences were 20 % BVI and 31 % LVI. BVI was associated with higher pathological stages on RC whereas LVI was associated with more nodal metastases. LVI showed good concordance. BVI showed low concordance overall but compared well in patients with MIBC and patients clinically assessed with non-organ confined disease. Our findings indicate that IHC in TURBT is a reliable tool, enabling increased VI detection and showing concordance of VI status between matched TURBT and RC. IHC may hold an improved prognostic potential as differentiating of BVI and LVI could contribute to better risk stratification at the time of TURBT.