Case of the Week

2019-3 / MARCH 4 (CONTRIBUTOR: JONATHAN EPSTEIN)

CASE HISTORY

A 25 year old man was found to have a 5.0 cm. paratesticular mass.

Click on the below thumbnails to enlarge photos.

JavaScript is not supported

JavaScript required. Your web browser either does not support JavaScript, or it is switched off. Some features may not work properly.

5 photo(s) Updated on: March 02, 2019

Please wait...
Please wait...
Please wait...
Please wait...
Please wait...

Quiz

What is the correct diagnosis?
a) De-differentiated liposarcoma

b) Synovial sarcoma

c) Malignant mesothelioma

d) Rhabdomyosarcoma

The tumor is biphasic. The spindle cell component consists of short fascicles of cellular spindle cells. Despite very high cellularity and cells having a high N/C ratio, imparting a very “blue” appearance at low magnification, there is relative uniformity in the atypia with a lack of pleomorphism. Focally, there are areas of collagen deposition. In addition, there is gland formation which is an integral component of the tumor. The cells within the glands are atypical and have similar cytology to the spindle cells. The tumor was focally pancytokeratin positive and on the outside stains was focally positive for inhibin and calretinin. S100 protein was negative. Given the morphology, molecular studies were performed and showed a translocation t(X;18)(p11;q11), consistent with synovial sarcoma. In an adult, the most common malignant spindle cell tumor in the paratesticular region would be a de-differentiated liposarcoma. However, these tumors in addition to having a well-differentiated liposarcoma component, would show greater pleomorphism and an haphazard array of the tumor cells. Rhabdomyosarcoma is the most common paratesticular malignant tumor in childhood and one of the variants is “spindle cell rhadomyosarcoma” which could mimic the spindle cell component in the current case, yet would lack a glandular component. The spindle cell component of a biphasic malignant mesothelioma would be more fibrous and not as monotonous and cellular. There are no cases reported as paratesticular synovial sarcomas, although the one reported case of a testicular synovial sarcoma is not clear whether it was intratesticular or paratesticular.

About GUPS

The Genitourinary Pathology Society (GUPS) was formed with the vision of advancing the care of patients with urologic diseases through enhancements of best practices, research, and education in the subspecialty of Urological Pathology.

GUPS is an official Companion Society of the United States and Canadian Academy of Pathology (USCAP).

Contact

gupathologysociety@gmail.com

Powered by Wild Apricot Membership Software