Intraductal carcinoma of the prostate in an Irish prostate cancer patient cohort—an aggressive pathology and a strong familial link

BACKGROUND: The prevalence of intraductal carcinoma of the prostate (IDC-P) is poorly studied in the Irish population. This study investigated the incidence and clinicopathologic characteristics of IDC-P in an Irish prostate cancer (PCa) patient cohort. The study also discusses the rationale for genetic counseling and screening in Irish patients with familial risk factors for IDC-P. MATERIALS AND METHODS: This study investigated patients diagnosed with IDC-P on prostate biopsy from 2012 to 2016. Primary outcome measurements were incidence, management, and clinical outcomes after follow-up in patients with IDC-P. The secondary outcome measurement was to identify a familial link for IDC-P. RESULTS: A total of 1,143 patients were diagnosed with PCa on needle biopsy, of which 30 (2.3%) had concomitant IDC-P. Mean age and prostate-specific antigen at diagnosis were 68.6 ± 10.5 years (range 53–85 years) and 9.15 ± 8.65 ng/mL (range 2.1–166 ng/mL), respectively. In total, 17 of 30 patients (57%) were diagnosed with concomitant high-grade (i.e., ≥Gleason score 8) PCa. Eight patients (27%) were treated with radical prostatectomy; of which five had biochemical recurrence (BCR) after 10.55 ± 25.9 months. Eleven patients (37%) received radical radiotherapy; of which one had BCR after 36 months. Eleven patients (37%) presented with advanced PCa and were managed with androgen deprivation therapy ± chemotherapy. A family history for PCa in first-degree relatives was found in eight patients (27%). CONCLUSIONS: IDC-P is associated with more aggressive clinicopathologic features and an increased risk of BCR after treatment. In Ireland, clinical guidelines and a genetic screening pathway are required to provide early detection and appropriate multimodal management of patients with IDC-P.