Intraductal carcinoma of the prostate: conflicting recommendations confuse clinicians

Intraductal carcinoma of the prostate (IDCP) generally represents a growth pattern of invasive aggressive acinar prostate cancer but may rarely represent a non-invasive putative precursor of prostate cancer.1 IDCP in needle biopsies may be encountered in isolation or in association with invasive prostate cancer. While there is consensus that pure IDCP in needle biopsies should not be graded, it is controversial whether IDCP associated with invasive cancer should be included in the Gleason score (GS). The International Society of Urological Pathology (ISUP) recommended incorporating the IDCP component into the GS, but the Genitourinary Pathology Society (GUPS) proposed grading only the invasive component with comments on the presence of associated IDCP and its adverse prognostic significance.2 3 The impact of these conflicting recommendations is greatest in needle biopsies with invasive GS 3+3 and extensive IDCP because such cases would be graded as at least GS 4+3 (grade group 3) based on the ISUP guidelines but GS 3+3 (grade group 1) as per the GUPS recommendation. In this issue, McDonald et al describe such a case where the …