p63-expressing prostatic adenocarcinoma

Prostatic adenocarcinoma with aberrant diffuse expression of p63 (p63-PCa) is a recently described variant of prostatic adenocarcinoma. (23774168, 18300803)

p63-PCa can show a distinctive morphology consisting of atrophic, poorly formed glands, with multilayered and often spindled nuclei.

It is recommended that these tumors not be assigned a Gleason score and their favorable findings at RP be noted.

In a study of 8 cases [18300803], the tumors are organ confined with negative margins and there was no seminal vesicle involvement or lymph node metastasis.

The presence of p63 positive atypical glands with an infiltrative pattern and perineural invasion on radical prostatectomy confirms the needle biopsy diagnosis of carcinoma.

Rarely, prostate cancer can aberrantly express diffuse p63 staining in a non-basal cell distribution leading to the erroneous diagnosis of atrophy or atypical basal cell proliferation.

The diagnosis of prostate cancer is based on the morphology and confirmed by the absence of high molecular weight cytokeratin staining and positivity for alpha-methylacyl-CoA racemase in the atypical glands.

Pathologists need to be aware of this rare and unusual phenomenon, which is a potential pitfall in prostate cancer diagnosis.

Images

 https://twitter.com/AdamGomezMD/status/711312234920546304

See also

 prostate adenocarcinoma

References

 Aberrant diffuse expression of p63 in adenocarcinoma of the prostate on needle biopsy and radical prostatectomy: report of 21 cases. Osunkoya AO, Hansel DE, Sun X, Netto GJ, Epstein JI. Am J Surg Pathol. 2008 Mar;32(3):461-7. doi : 10.1097/PAS.0b013e318157020e PMID: 18300803