Spermatic Cord Desmoplastic Small Round Cell Tumor
Desmoplastic small round cell tumor (DSRCT) is a high-grade aggressive round cell tumor of uncertain histogenesis, associated with prominent stromal desmoplasia and polyphenotypic differentiation.
Paratesticular DSRCT is very rare with approximately 20 such cases reported in the literature.
Like DSRCT at other sites, it is seen in older adolescents and young adults.
Surgical resection, often with orchiectomy, is the preferred local treatment. Radiotherapy may also be used. Chemotherapy is part of the standard therapy, both in the neoadjuvant and adjuvant setting.
The overall survival is poor, ranging between 15% and 30% at 5 years. However, tumors in the paratesticular location have a better survival, possibly because they are detected earlier and they are more amenable to complete surgical resection.
DSRCT usually appears as a multilobulated or multinodular mass, with a firm cut surface, often with foci of hemorrhage and necrosis.
DSRCT consists of multiple nodules, each composed of nests of uniform round cells with scant cytoplasm, separated by dense bands of collagen (Fig. 1). Areas of necrosis and brisk mitotic activity are usually detected.
Immunohistochemically, this tumor is polyphenotypic, staining for vimentin, keratins, EMA, desmin, and NSE. Myogenin, CD99, CD3, CD45, CD20, and inhibin are negative.
DSRCT is characterized by a recurrent t(11;22) (p13;q12) resulting in the fusion of the Ewing sarcoma gene, EWS, on 22q12 and the Wilms tumor gene, WT1, on 11p13.