Metanephric stromal tumor

Metanephric stromal tumor was more recently described (Fig. 24.20) (Argani and Beckwith 2000). Mean patient age at diagnosis is 2 years. Gross examination typically revealed a fibrous lesion centered in the renal medulla containing smooth-walled cysts. Metanephric stromal tumor is histologically identical to the stromal component of metanephric adenofibroma. Patients may be treated with surgical excision alone. 

Fig. 24.20. Metanephric stromal tumor in a 3.5-year-old girl. Contrast-enhanced CT (sagittal reconstruction). Renal mass incidentally discovered during US performed for enuresis. Pathological diagnosis obtained after neoadjuvant chemotherapy (30% volume response only) and nephrectomy for presumed Wilms tumor...

Argani P, Beckwith JB (2000) Metanephric stromal tumor report of 31 cases of a distinctive pediatric renal neoplasm. Am J Surg Pathol 24(7) 917-926... 

Wilms tumor protein-1 (WT-1) Nephroblastoma, mesothelioma, metanephric adenoma, ovarian serous carcinoma AML, desmoplastic small round cell tumor, endometrial stromal sarcoma, uterine leiomyosarcoma, granulosa cell tumor, thecoma, rhabdoid tumor Kidney, mesothelial cells, granulosa cells, Sertoli cells, fallopian tube endometrial stroma, spleen... 

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