Central pathology review and its prognostic value in upper tract urothelial carcinoma patients: a nationwide multi-institutional study

The prognostic value of central pathology review in upper urinary tract cancer (UTUC) remains inadequately addressed in existing literature. In this study, we conducted an extensive central pathology review and presented its influence on multi-center UTUC studies. We conducted a retrospective review of patients who underwent radical nephroureterectomy or segmental resection for UTUC to determine eligibility for central pathology review. In the Taiwan UTUC Collaboration cohort, 377 cases met the criteria for pathology review. We assessed agreement between pathologists using both the total percentage of agreement and simple kappa statistics. The prognostic implications of original and review pathology for various parameters were examined using the Cox regression model. This study included 209 female and 168 male participants. Pathology review revealed substantial interobserver variability in pT staging, with a particularly high rate of pT2 cases being upgraded to pT3 upon central review (17/70 pT2 stage made by local pathologists were finally confirmed as pT3 disease by the review pathologist). The local pathologist cohort identified fewer significant histological predictors in survival models compared to the review pathology cohort. Advanced pT stage, perineural invasion (PNI), and positive surgical margin were independent predictors of poorer overall survival and cancer-specific survival. PNI, lymphatic vascular invasion, and positive surgical margin were independent predictors of disease recurrence. Substantial interobserver variability in histological assessment underscores the importance of centralized pathology review for both multi-center studies and accurate post-operative management of UTUC patients. Advanced stage, perineural invasion, and margin status were significant histological predictors of oncological outcomes.