Seminal epithelium in prostate biopsy can mimic malignant and premalignant prostatic lesions

Atypical small acinar proliferation and its significance in pathological reports in modern urological times

Atypical small acinar proliferation is a histopathological diagnosis of unspecified importance in prostate needle-biopsy reports, suggestive but not definitive for cancer. The terminology corresponds to some uncertainty in the biopsy report, as the finding might represent an underlying non-cancerous pathology mimicking cancer or an under-sampled prostate cancer site. Therefore, traditional practice favors an immediate repeat biopsy. However, in modern urological times, the need of urgent repeat biopsy is being challenged by some authors as in the majority of cases, the grade of cancer found in subsequent biopsy is reported to be low or the disease to be non-significant. On the other hand, high risk disease cannot be excluded, whereas no clinical or pathological factors can predict the final outcome. In this review, we discuss the significance of the diagnosis of atypical small acinar proliferation in the biopsy report, commenting on its importance in modern urological practice.

Usefulness of GATA-3 as a marker of seminal epithelium in prostate biopsies

OBJECTIVES

The incidental presence of seminal vesicle epithelium in prostate needle biopsies is generally recognisable through routine microscopy. However, the biopsy can sometimes be erroneously interpreted as malignant due to its architectural and cytological characteristics, and immunohistochemistry can be useful for correctly identifying the biopsy. Our objective was to analyse the potential usefulness of GATA-3 as a marker of seminal epithelium.

MATERIAL AND METHODS

Through immunohistochemistry with a monoclonal anti-GATA-3 antibody (clone L50-823), we studied seminal vesicle sections from 20 prostatectomy specimens, 12 prostate needle biopsies that contained seminal vesicle tissue and 68 prostate biopsies without seminal vesicle epithelium, 36 of which showed adenocarcinoma.

RESULTS

Staining for GATA-3 was intense in the 20 seminal vesicles of the prostatectomy specimens and in the 12 prostate needle biopsies that contained seminal epithelium. In the 60 biopsies without a seminal vesicle, GATA-3 was positive in the prostate basal cells and even in the secretory cells (57 cases), although with less intensity in 55 of the cases. One of the 36 prostatic adenocarcinomas tested positive for GATA-3.

CONCLUSIONS

The intense immunohistochemical expression of GATA-3 in the seminal vesicle epithelium can help identify the epithelium in prostate biopsies. This marker is also positive in the basal cells of healthy prostates and, with less intensity, in the secretory cells. Positivity, weak or moderate, is observed on rare occasions in prostatic adenocarcinomas.