Home Chapter Home Jobs Conferences Fellowships Books
Advertisement
Penis and scrotum
Neoplastic lesions of scrotum
Desmoplastic round cell tumor
Editors: Antonio Cubilla, M.D. and Alcides Chaux, M.D. (see Author/Reviewers page)
Revised: 22 May 2010, last major update May 2010
Copyright: (c) 2002-2010, PathologyOutlines.com, Inc.
Definition
=========================================================================
● Rare tumor, often fatal, that typically affects abdominal or pelvic peritoneum of children and young male adults, and expresses epithelial, neural and muscular markers (Am J Surg Pathol 1991;15:499)
● First described in 1989 (Pediatr Pathol 1989;9:177)
● See also testis chapter
Epidemiology
=========================================================================
● Mean age 27 years
● Rarely arises in scrotum (Am J Surg Pathol 1997;21:219, Am J Surg Pathol 1998;22:1303)
Clinical features
=========================================================================
● Poor prognosis at all sites, with frequent death from disease
Case reports
=========================================================================
● 17 year old boy (J Surg Oncol 1999;71:269)
● 28 year old man with abdominal tumor and scrotal metastases (Radiographics 1999;19:252)
Treatment
=========================================================================
● Surgery plus chemotherapy
Gross description (Macroscopy)
=========================================================================
● Multinodular, firm, bulky tumor with smooth bosselated surfaces
● Cut surface is gray-white with sharply demarcated areas of necrosis/hemorrhage
Gross images
=========================================================================
Tunica vaginalis is distended and studded Various images-site unspecified
by a gray-white mass
AFIP image courtesy of Dr. J. Prat,
Barcelona, Spain
Micro description (Histopathology)
=========================================================================
● Irregular, sharply demarcated clusters of small round cells embedded in a dense fibrous/fibromyxoid stroma
● Neoplastic cells are undifferentiated, with small round to oval hyperchromatic nuclei with inconspicuous nucleoli and scant cytoplasm
● Foci of necrosis are common, especially in larger tumor nests
● Areas of more pleomorphic, atypical, epithelioid or spindle cells are seen in 1/3 of cases
● Occasionally rhabdoid cells, signet ring-like cells and tubular-like structures
Micro images
=========================================================================
Nests of cells with scant cytoplasm in desmoplastic stroma
Scrotal metastasis Various images - sites unspecified
Site unspecified
Fig A: bands of collagen separating clusters of small round blue cells
Fig B: Tumor cells have hyperchromatic nuclei and coarse chromatin; mitotic figures are present
Fig C: CD99+
Fig D: Desmin staining is dot-like (punctuate)
Cytology images
=========================================================================
Site unspecified - small round blue cells
Positive stains
=========================================================================
● Epithelial, neural and muscular markers
● AE1/AE3, CAM 5.2, desmin (dot-like perinuclear pattern), neuron-specific enolase, WT1
Negative stains
=========================================================================
● Actin
Molecular / cytogenetics description
=========================================================================
● t(11;22)(p13;q12) - EWS-WT1 fusion in most cases (Cancer Res 1994;54:2837, Proc Natl Acad Sci USA 1995;92:1028)
Differential diagnosis
=========================================================================
● Embryonal rhabdomyosarcoma: mean age 7 years, more cellular, more myxoid stroma, occasional rhabdomyoblasts
● Lymphoma: no nested pattern, no desmoplastic stroma, positive for B and T cell markers
● Retinal anlage tumor: melanin pigment , HMB45+, NSE+, synaptophysin+, S100+
Additional references
=========================================================================
End of Penis and scrotum > Neoplastic lesions of scrotum > Desmoplastic round cell tumor
This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must also be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.
All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).