Diagnostic issues in second opinion consultations in prostate pathology

Aim: The increase in early detection of prostate cancer in the Asian population has bolstered second opinion consultations in prostate pathology in this region. In this review, we aimed to identify the spectrum of lesions and queries submitted to a pathologist with uropathology interest at the Singapore General Hospital. Method: Request forms for second opinion prostate consultations from pathologists and clinicians were retrieved from central laboratory records and a specialist's correspondence files within 2004-2007. Histomorphological queries raised in the referrals, and comparison of original diagnosis and Gleason scoring with the review diagnoses were collated. Results: Discordant diagnoses (183/323, 57%) were more common than concordant diagnoses (143/326, 44%) between original diagnosis and subspecialist review. The majority of discordances comprised initial undergrading of Gleason scores (132/183, 72%; p < 0.01) especially in needle core biopsies. Among the significantly altered pathological diagnoses, 24 cases (13%; p < 0.01) were changed from benign to malignant (n = 9, 5%; p < 0.01), and malignant to benign (n = 11, 6%; p < 0.01) or high grade prostatic intraepithelial neoplasia (n=4, 2%; p < 0.01). Benign mimics of malignancy such as atypical adenomatous hyperplasia and atrophy, and small foci of adenocarcinoma, were some examples of morphological pitfalls. Conclusion: Prostate biopsy review is important because of management and prognostic implications that vary among Gleason scores, and predictive parameters that are detailed in prostate pathology reports.