Desmoplastic Small Round Cell Tumor of the Kidney

Abstract

Desmoplastic small round cell tumor (DSRCT) is a rare, aggressive, malignant tumor usually present with widespread abdominal serosal involvement. Isolated cases occur in limbs, head and neck, and brain. We present a case of primary DSRCT of the kidney in a 41-year-old man. The tumor showed morphologic, immunohistochemical, and molecular characteristics similar to DSRCTs arising in other sites. Epithelial and mesenchymal markers were coexpressed in the tumor cells. RT-PCR analysis showed EWS-WT1 fusion transcripts resulting from the t(11;22)(p13;q12) reciprocal translocation. DSRCT should be considered in the differential diagnosis of small blue round cell tumors of the kidney.

A new molecular variant of desmoplastic small round cell tumor: significance of WT1 immunostaining in this entity

“…Of these, 3 cases with variant transcripts have been reported; all were soft tissue tumors with EWS-WT1 9/8 variant transcripts [10,15,17]. The EWS-WT1 9/8 transcript has also been identified in DSRCT of the kidney [16]. Because the number of cases with variant transcripts and atypical locations is low, it is difficult to prove an association between site of origin and a specific transcript.…”

“…In most cases of DSRCT, the EWS-WT1 fusion transcript consists of the first 7 exons of the EWS gene and the last 3 exons (exons 8-10) of the WT1 gene (EWS-WT1 7/8) [7]. However, several alternative breakpoints for the t(11;22)(p13;q12) translocation have been described [8][9][10][11][12][13][14][15][16][17]. The resulting fusion transcripts generally contain additional exons from EWS with conservation of the WT1 complement (EWS-WT1 8/8, 9/8, and 10/8).…”

Soft tissue tumors associated with EWSR1 translocation

“…Originally, described as a predominantly intra-abdominal tumor, a broader distribution has emerged gradually that includes pleura [61] and tunica vaginalis [62]. Extraserous location has been occasionally reported, including parotid gland [63], posterior cranial fossa [64], central nervous system [65], bone and soft tissue [66][67][68], ovary [69], pancreas [70], and kidney [71,72].…”

Desmoplastic Small Round Cell Tumor in Transverse Colon: Report of a Rare Case

“…4 Very rarely, DSRCT can arise from the head and neck, base of skull, paratesticular region, ovary, brain, or thoracic viscera. 10 Extraperitoneal organ involvement is inconstant and secondary; including lung, 11 liver, 12 kidney, 13 stomach, 14 and pancreas. 15 Liver and lungs are the 2 most common sites of distant metastasis.…”