Prostate cancer with comedonecrosis is frequently, but not exclusively, intraductal carcinoma: a need for reappraisal of grading criteria.
AIMS: Comedonecrosis in prostate cancer has always been Gleason pattern 5. However, we aimed to evaluate how intraductal carcinoma (not graded) with comedonecrosis should be considered.
METHODS AND RESULTS: From 52 radical prostatectomy patients, 40 were informative and evaluated with immunohistochemistry for basal cells. Clinical outcome was assessed for biochemical recurrence, metastatic disease, and the need for adjuvant therapy. Comedonecrosis was predominantly located in intraductal carcinoma (24, 60%). However, 9 (23%) had comedonecrosis within invasive cancer and 7 (18%) within both invasive and intraductal carcinoma. Extraprostatic extension rarely contained comedonecrosis (5, 13%) instead usually containing perineural invasion within cribriform glands. Tumors were overwhelmingly high-stage (15, 38% pT3a and 19, 48% pT3b) with 15 (37%) having positive lymph nodes and 4 having distant metastases. Most (25, 63%) had other patterns of Gleason pattern 5 (single cells, solid), although 10 were reclassified as containing no invasive pattern 5. Of these, most were pT3 (8/10), but none had positive lymph nodes. Lymph node metastases were more common in patients with invasive cancer containing comedonecrosis (p=0.02), and the need for androgen deprivation was near-significant (p=0.07), but biochemical recurrence was not significantly different (p=0.58).
CONCLUSIONS: Prostate cancer with comedonecrosis is often intraductal; however, these tumors are overwhelmingly high-stage, showing a higher rate of positive lymph nodes with invasive comedonecrosis. Immunohistochemistry may be considered when comedonecrosis may significantly change the tumor grade. However, it is not clear at present that excluding intraductal carcinoma from the grade is superior when associated with high-grade invasive cancer. This article is protected by copyright. All rights reserved.
ePub ahead of print