Desmoplastic small round cell tumor

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

Synonyms and keywords: Desmoplastic small round cell tumour; Desmoplastic small round blue cell tumor; Desmoplastic small round blue cell tumour; Intraabdominal desmoplastic small round blue cell tumor; Desmoplastic small cell tumor; Desmoplastic cancer; Desmoplastic sarcoma; DSRCT

Overview

Desmoplastic small round cell tumor is a rare but highly fatal malignancy.

Historical Perspective

Desmoplastic small round cell tumor was first described by pathologists, William L. Gerald and Juan Rosai, in 1989.

Pathophysiology

Pathogenesis

Desmoplastic small round cell tumor is a highly aggressive, rare tumor of mesenchymal origin whose oncogenic effect is presumed to originate from the unique chromosomal translocation t(11;22)(p13:q12), leading to the fusion of the N-terminal domain of Ewing’s sarcoma gene EWS, to the C-terminal domain of Wilms’ tumor suppressor gene, WT1, which is found in most but not all desmoplastic small round cell tumors.

Gross Pathology

Desmoplastic small round cell tumor tends to grow along a serosal lining, most commonly the peritoneal surface, but other primary sites have been described.

Gallery

• 

  _{Micrograph of a desmoplastic small round cell tumor, showing the characteristic desmoplastic stroma and angulated nests of small round cells on H&E stain.}

• 

  _{Display of small round blue cells characteristic of desmoplastic small-round-cell tumor.}

• 

  _{Cell exhibiting blue oval and round shapes of desmoplastic small round blue cell tumor.}

Differentiating Desmoplastic Small Round Cell Tumor from other Diseases

• Desmoplastic small round cell tumor in the abdomen may cause gastrointestinal symptoms and mimic other abdominal tumors. So, they must be differentiated from other tumors in the abdomen, such as:

• Rhabdomyosarcoma
• Neuroblastoma
• Mesenteric carcinoid

Epidemiology and Demographics

Incidence

• Age-adjusted incidence rate of desmoplastic small round cell tumor for African Americans and Caucasians is 0.05 and 0.02 per 100,000 individuals, respectively.
• The overall age-adjusted incidence rate of desmoplastic small round cell tumor is 0.03 per 100,000 individuals, with a peak incidence of 0.074 per 100,000 individuals in the 20–24 years of age group.

Age

Peak age of incidence for desmoplastic small round cell tumor is between 20 and 24 years.

Gender

Males are more commonly affected with desmoplastic small round cell tumor than females. The male to female ratio is approximately 4 to 1.

Race

Desmoplatic small round cell tumor usually affects individuals of the African American and Caucasian race. Latin American and Asian individuals are less likely to develop desmoplatic small round cell tumor.

Gallery

_{(a) Overall age-adjusted incidence of desmoplastic small round cell tumor, (b) Sex-based age-adjusted incidence of desmoplastic small round cell tumor. Males are more likely than females to get desmoplastic small round cell tumor, (c) Race-based, age-adjusted incidence of DSRCT. African Americans are more likely than Caucasians to get desmoplastic small round cell tumor.}

Demographics

_{Adapted from Christina K. Lettieri et al.}

Risk Factors

There are no established risk factors for desmoplastic small round cell tumor.

Natural History, Complications, and Prognosis

Prognosis

Gallery

_{(a) Race-based survival of desmoplastic small round cell tumor. There may be a survival disadvantage for African americans compared to Caucasians. Although it did not reach statistical significance, this analysis suggests that African americans are 33% more likely to succumb to desmoplastic small round cell tumor than are Caucasians, (b) Treatment-based survival of desmoplastic small round cell tumor, radiation versus no radiation. There was no statistically significant difference in survival amongst patients who received radiation therapy compared to those who did not, (c) Treatment-based survival of demsoplastic small round cell tumor, radiation after surgery versus no radiation. Patients who received radiation following surgery fared better than those patients who did not.
Adapted from Christina K. Lettieri et al.}