The diagnostic challenges of differentiating metastatic extramammary Paget disease and prostatic adenocarcinoma: A case report and review of the literature.

Extramammary Paget disease (EMPD) is a rare dermatologic malignancy with a high rate of recurrence and increased risk for developing secondary malignancies. We present a 74-year-old male with previously resected primary EMPD who presented with widespread PSMA-avid lesions without prostatic uptake, an elevated PSA >100, and a negative prostate biopsy. Based on this and immunohistological staining, recurrent EMPD was suspected. However, after additional staining and reexamining their clinical presentation, metastatic prostate cancer without a detected primary lesion is more probable. This case highlights the diagnostic challenge variable expression of shared biomarkers found in EMPD and prostate cancer present to clinicians.
Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Viraj Master reports financial support was provided by Crotts Initiative. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(© 2024 Published by Elsevier Inc.)