Table of Contents
Definition / general | Terminology | Epidemiology | Sites | Pathophysiology and Etiology | Clinical features | Case reports | Treatment | Gross description | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Electron microscopy description | Differential diagnosisCite this page: Male adnexal tumor of probable Wolffian origin. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/testisparatest.html. Accessed July 15th, 2017.
Definition / general
- Benign tumor believed to arise from Wolffian duct remnants
- See also Female adnexal tumor of Wolffian origin
Terminology
- Also called Wolffian hamartoma
- Sometimes grouped under the broad term of "benign epithelial proliferations"
Epidemiology
- Extremely rare in men, more common in women
- Usually presents as a tumor in 4th to 5th decade
Sites
- Paratesticular location, commonly around the rete testis, epididymis, vas deferens and seminiferous tubules
Pathophysiology and Etiology
- Tumors are believed to arise from Wolffian duct remnants, although precise etiology is unknown
- Though the incidence of Wolffian duct remnants is much higher, they are commonly incidental findings on autopsies or surgical specimens
Clinical features
- Symptoms include pain, difficulty initiating micturition and sexual dysfunction
- Most tumors are benign
- Single case of metastases reported (Scand J Urol Nephrol 2009;43:253), although as reported, malignant mesothelioma cannot be excluded
- Biopsy / surgical excision required for definitive diagnosis
Case reports
- 29 year old man with tumor in seminal vesicle (Histopathology 1998;33:269)
- 46 year old man with tumor of probable paradidymal origin (Am J Clin Pathol 1994;101:543)
- 47, 48 and 50 year old men with tumors (Ann Diagn Pathol 2013;17:151)
- 56 year old man (Scand J Urol Nephrol 2005;39:520)
Treatment
- Surgical excision
Gross description
- 4 - 8 cm, multicystic
- Distinct from epididymis and vas deferens
Microscopic (histologic) description
- Unilocular or multicystic mass lined by a single layer of cuboidal to tall columnar epithelium with apical cilia
- Secretions are commonly seen on apical aspect of cells and in lumen
- Nuclei are usually bland with little pleomorphism or mitosis
- Cysts are surrounded by variable connective tissue / fibromuscular stroma
- Lymphovascular emboli or invasive features are usually absent
Positive stains
- PAX8, PAX2 (Am J Surg Pathol 2011;35:1473)
- CK7, CD10 (relatively specific for Wolffian duct origin in paratesticular tumors)
- Apical secretions are PAS positive, diastase resistant
- Androgen receptor positivity
Negative stains
Electron microscopy description
- Short villi are prominent unlike the long bushy villi of mesothelioma
- Intraluminal flocullent densities representing secretions and free ribosomes are prominent
- Mitochondria are sparse
Differential diagnosis
- Malignant mesothelioma: calretinin+, HBME1+
- Metastatic adenocarcinoma: prostatic adenocarcinoma is PSA+
- Ovarian surface epithelial tumors: mucinous or serous lining


