Clinical significance of interobserver differences in the staging and grading of superficial bladder cancer

Abstract

Objective To assess the reliability of the histological diagnosis of bladder cancer by assessing the interobserver variability of staging and grading in pTa/pT1 tumours and evaluating the clinical signi®cance of discrepancies. Materials and methods All sections from 301 super®cial bladder carcinomas were reviewed by one pathologist. The prognostic relevance of grade and stage from both the initial and review diagnosis were determined in 128 patients for whom there was long-term follow-up information. Results There were signi®cant interobserver differences in both the grading and staging of tumours. From a total of 235 tumours that were initially considered pT1, the reviewer classi®ed 35% as pTa, 56% as pT1, 6% as pT1-(at least pT1), and 3% as pT2±4. In 39% of all biopsies there were interobserver differences in tumour grade. The prognostic signi®cance of grade and stage differed between the initial pathology report and the reviewer's diagnosis. The reviewer's staging allowed a better estimate of the risk of subsequent tumour progression than the initial staging. Progression was signi®cantly more common in 49 tumours in which the reviewer agreed with stage pT1 than in 29 tumours that were down-staged from pT1 to pTa (P = 0.0116). However, the initial tumour grade (P = 0.0386) but not the reviewer's grade (P = 0.2645) was signi®cantly linked to progression. Conclusions These results show that grading and staging by different pathologists have varying prognostic implications. If possible, biopsies from bladder tumours should be independently evaluated by two different pathologists before radical therapy is administered.

Mcm2 predicts recurrence hazard in stage Ta/T1 bladder cancer more accurately than CK20, Ki67 and histological grade

“…Despite control TURB in all 71 Ta/T1 BC of the present series to enhance completeness of resection 35% experienced recurrences. Histopathological evaluation is the gold standard to predict clinical behaviour of Ta/T1 BC, despite recognised limitations such as high interobserver variability (Tosoni et al, 2000). Numerous markers have been evaluated to enhance the prognostic power of histopathological evaluation.…”

“…Thus reliable prognostic parameters differentiating high-and low-risk patients with stage Ta/T1 urothelial carcinoma of the bladder (Ta/T1 BC) might enable individual risk adapted follow-up regimes. Despite high interobserver variation, histological grading is the most commonly used predictor of prognosis in Ta/T1 BC (Tosoni et al, 2000). Two well-established markers of recurrence are MIB-1 and CK20.…”

Staging and reporting of urothelial carcinoma of the urinary bladder

“…In one study, 35% of carcinomas initially diagnosed as stage pT1 were downstaged to pTa, and 3% were upstaged as pT2-4 carcinomas. 21 In another study, there was complete interobserver agreement on pT1 stage among reviewers in 80% of cases, which rose to 88% after a second review. 22 Of the 63 tumors originally diagnosed as stage pT1, the consensus diagnosis by experienced genitourinary pathologists resulted in downstaging of 35 (56%) to pTa and upstaging of 8 (13%) to pT2-pT3 tumors.…”

Prediction of recurrence in Ta urothelial cell carcinoma by real‐time quantitative PCR analysis: A microarray validation study

“…[1][2][3] Although these factors are relatively accurate in the group of patients with superficial UCC, improvement in the prediction of tumor recurrence in individuals is needed. [4][5][6] Many studies have investigated the prognostic potential of molecular markers to supplement or even replace the current standards. Several markers show a relationship with early tumor recurrence in patients with superficial UCC.…”