Differing interpretations by pathologists of the pT category and grade of transitional cell cancer of the bladder

The UICC pT category for transitional cell cancer (TCC) of the bladder was recorded as assigned from the routine service of a pathology laboratory. All reports had been passed for release after review by pathologists of the status of senior registrar or above. After 99 cases had been collected, the slides available to the original pathologist were reviewed by one dedicated pathologist in continuous session who was ignorant of the original report. No new sections were cut. There was disagreement with the original report of pT category in 14 cases: 13 were downstaged (including 6 from invasive to superficial) and 1 upstaged. There was disagreement with the original differentiation grade in 13 cases: 10 TCC were considered to be more differentiated and 3 less differentiated than the original report. A second pathologist reviewed the pT category only of 13 of the 14 cases, disagreeing with the original pT category on 8 occasions and with the pT category assigned by the dedicated pathologist on 7 occasions. These findings have important implications for advising patients on prognosis and clinical management and in the design and reporting of therapeutic trials.