Reliability of the 34βE12, keratin 5/6, p63, bcl-2, and AMACR in the diagnosis of prostate carcinoma.

OBJECTIVE

In this study, we aimed to investigate which basal cell marker should be used with α-methylacyl coenzyme A racemase (AMACR) to increase diagnostic accuracy in the diagnosis of prostate carcinoma.

MATERIALS AND METHODS

A total of 98 cases of prostate biopsy, comprising 65 cases with prostate adenocarcinoma and 33 cases without adenocarcinoma, were included in this study. Prostate-specific antigen (PSA) serum levels before biopsies were obtained. The number of cores with malignant glands and Gleason scores for each case were determined. Paraffin sections were stained immunohistochemically with 34βE12, keratin 5/6, p63, bcl-2, and AMACR.

RESULTS

According to staining pattern, extensiveness, and intensity of basal cell markers in benign glands, 34βE12 gave the best results. As negative markers for prostate adenocarcinoma, the best markers were p63 and 34βE12. According to the AUC values in ROC curves for both extensiveness and intensity, the arrangement from the best to the worst was 34βE12, p63, bcl-2, and keratin 5/6. The 34βE12 had the best sensitivity and specificity values (95% and 98%, respectively). Staining extensiveness and intensity of keratin 5/6 in malignant glands, and those of bcl-2 in benign glands had statistically significant positive correlation with serum PSA levels. Even though AMACR is a negative marker for benignity, some of the benign glands also had positive immune reaction with AMACR. However, AMACR positivity was usually focal and weak. Nevertheless, intensively stained subjects were also present. No correlation was present between AMACR and basal cell markers.

CONCLUSIONS

As a result, we suggest that keratin 5/6 and bcl-2 should not be used to identify benign glands in prostate biopsy since they show high positivity in malignant glands and high negativity in benign glands. 34βE12 should be the first choice as a basal cell marker. p63 can be used together with 34βE12, but it may not give additional diagnostic information. When we evaluated the correlation of basal cell markers, we did not find any complementary staining results among basal cell markers. Our study showed that 34βE12 is the most appropriate negative marker to combine with AMACR as a positive marker for the diagnosis of prostate adenocarcinoma.