Adenomatoid tumor

Adenomatoid tumor
ICD-O:	9054/0
MeSH	D018254

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Sara Mohsin, M.D.[2]

Overview

Adenomatoid tumor is a mesothelial tumor. It generally presents in the genital tract, in regions such as the testis and epididymis. However, it also has been found in the pancreas.

Pathophysiology

Adenomatoid tumors are benign, solid extratesticular lesions that can originate from the epididymis, tunica vaginalis, or spermatic cord. They are the most common tumor of the epididymis. They occur more often in the lower pole than in the upper pole by a ratio of 4:1. Usually an incidental finding, adenomatoid tumors manifest as a painless scrotal mass, with the majority diagnosed in patients aged 20–50 years. They are typically unilateral and occur more frequently on the left side. When they grow noninvasively into the testicular parenchyma, they can simulate intratesticular disease.

Diagnosis

Ultrasound findings

• On an ultrasound, they appear as a solid extratesticular mass with variable echogenicity.

MRI

• Commonly, MRI demonstrates low signal intensity relative to the testicular parenchyma on T2-weighted images.
• MRI can aid in determining the paratesticular origin of the lesion.
• Adenomatoid tumors enhance after administration of gadolinium contrast material.

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  T2
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  T2
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  STIR
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  T1 pre contrast
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  T1 post GAD