Prostate gland & seminal vesicles

Benign mimickers of carcinoma

Mesonephric remnant hyperplasia



Topic Completed: 1 July 2016

Minor changes: 3 September 2020

Copyright: 2002-2020, PathologyOutlines.com, Inc.

PubMed Search: Mesonephric remnants

Andres Matoso, M.D.
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Cite this page: Matoso A. Mesonephric remnant hyperplasia. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/prostatemesonephrichyper.html. Accessed December 3rd, 2021.
Definition / general
  • Mesonephric remnant hyperplasia is a proliferation of small glands that mimic prostatic carcinoma
  • This is more common in the female genital tract and can rarely be seen within the prostate
Essential features
  • Cluster of small acini with eosinophilic secretion, cells with bland nuclei and inconspicuous nucleoli usually in a lobular distribution
  • An infiltrating pattern can be seen occasionally, mimicking cancer
  • Papillary infolding or small ill formed glands may mimic high grade prostate cancer
  • No clinical significance
Epidemiology
  • Mean age 60 years (range, 40 to 80 years)
Sites
  • Prostate and periprostatic tissue
Pathophysiology
  • Believed to represent an embryologic remnant
Clinical features
  • Asymptomatic
Prognostic factors
  • Not associated with increased risk of cancer
Treatment
  • Not required
Microscopic (histologic) description
  • Cluster of small acini with eosinophilic secretion, with cells with bland nuclei and inconspicuous nucleoli usually in a lobular distribution
  • An infiltrating pattern can be seen occasionally, mimicking cancer
  • Papillary infolding or small ill-formed glands may mimic high grade prostate cancer
Microscopic (histologic) images

Contributed by Andres Matoso, M.D.

Positive stains
  • High molecular weight cytokeratin and p63 are typically positive but can be negative
  • Racemase can be focally positive; when positive, along with negative p63 and high molecular weight cytokeratin, can erroneously lead to a diagnosis of adenocarcinoma of the prostate
  • PAX8 is positive
Negative stains
Differential diagnosis
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