Intraductal prostate cancer: An aggressive subset of prostate cancers? Immunophenotypic evaluation

The presence of intraductal prostate cancer in a sample is often associated with large tumor volume, an advanced stage of the disease, a high Gleason score and an increased risk of recurrence, and resistance to androgen suppression and chemotherapy, which are also correlated with reduced progression-free survival and with postoperative, biochemical relapse.

The aim of our study was to investigate whether carbonic anhydrase IX (CA IX) is upregulated in prostate cancer and to investigate ERG and EZH2 as potential markers for cancer aggression in aggressive acinar disease with intraductal component prostate cancer. The series consisted of 79 cases of prostate cancer. Immunohistochemical staining was performed for EZH2 ERG and CA IX.

The results of this study underline the fact that EZH2 protein expression is a powerful predictor of PSA relapse in prostate cancer and that this effect is stronger in ERG-positive cancers than in ERG-negative cancers. Evident EZH2 nuclear expression was found in prostatic tumor, proposing increased EZH2 expression important for the spread of prostate cancer.

The relationship to tumor phenotype and prognosis was more considerable in ERG-positive tumors than in ERG-negative tumors. EZH2 has gained great interest as a target for epigenetic cancer therapy. Although prostate cancer is a hypoxic tumor, it does not express CA IX and cannot be used as an endogenous marker for hypoxia.