Prostatic marker-negative amphicrine carcinoma of the prostate

Area of Science:

• Oncology
• Pathology
• Cancer Biology

Background:

• Prostate adenocarcinoma differentiation typically correlates with prostatic-specific marker and neuroendocrine expression.
• Undifferentiated tumors show decreased prostatic markers and increased neuroendocrine cells, often associated with small cell morphology.
• Previous reports link complete absence of prostatic markers and marked neuroendocrine expression to small cell carcinoma.

Observation:

• This report describes a unique case of metastatic, prostatic marker-negative, non-small cell prostate adenocarcinoma with a prominent neuroendocrine component.
• Luminal-exocrine cells appeared ultrastructurally undifferentiated with sparse cytoplasm, contrasting with controls.
• Neuroendocrine cells, identified as eosinophilic cells, were significantly increased in metastatic foci compared to the primary tumor.

Findings:

• The neuroendocrine cells observed differed ultrastructurally from previously reported Paneth-like cells in prostate carcinoma.
• This case supports the concept of multidirectional differentiation in epithelial cancers.
• A strong association between poor tumor differentiation and neuroendocrine expression in prostate carcinoma is further supported.

Implications:

• The findings challenge the typical association of neuroendocrine expression solely with small cell prostate carcinoma.
• The presence of well-formed basal laminae in metastatic foci contrasts with prior observations.
• This case highlights the complexity of prostate cancer differentiation and potential therapeutic targets.