Intraductal carcinoma of prostate (IDC-P) and high-grade prostatic intraepithelial neoplasia (HGPIN) in prostate biopsy: why we should distinguish one from the other

• Published in: Pathology 2013, Vol.45, p.S70-S71
• Main Authors: Jayasinghe, Sureshni I., Clouston, David
• Format: Article
• Language: English
• ISSN: 0031-3025; 1465-3931
• DOI: 10.1097/01.PAT.0000426890.69262.45

To explore the distinction between Intraductal carcinoma of prostate (IDC-P) and high-grade prostatic intraepithelial neoplasia (HGPIN). A case of IDC-P is presented with review of literature. Transurethral resection of prostate showed extensive IDC-P associated with a smaller component of Gleason pattern 5+5 adenocarcinoma. HGPIN was not identified. Prostate biopsies performed immediately prior were reported as HGPIN associated with Gleason pattern 5+5 adenocarcinoma. IDC-P is an uncommon entity characterised by malignant cells that fill and expand pre-existing prostatic ducts and glands, with an intact basal cell layer, featuring cribriform or solid pattern with or without comedonecrosis.1 Morphological criteria have been proposed to distinguish IDC-P from several other lesions including HGPIN.1,2 IDC-P and HGPIN are biologically distinct entities supported by emerging molecular data and leading to differences in patient management.1,2 While HGPIN is postulated to be an early precursor lesion in some carcinomas, IDC-P almost always co-exists with aggressive prostate cancer in radical prostatectomy featuring higher Gleason score, larger tumour volume, greater risk of extra-prostatic extension, seminal vesicle invasion and pelvic lymph node metastasis.2–4 It is crucial to recognise IDC-P, particularly as an isolated finding in prostate biopsies, in order to implement immediate definitive therapy for high grade carcinoma even in the absence of invasion.1–4