Metachronous Synovial Sarcoma After Treatment of Mixed Germ Cell Tumor in a Child with Complete Gonadal Dysgenesis

Abstract

Patients with complete XY gonadal dysgenesis (GD) show a high predisposition to germ cell tumors (GCT). Patients with coexistence of GCT and GD have been reported previously. Here we present a 15-year-old girl with mixed GCT and GD who also developed an intra-abdominal synovial sarcoma one year after the treatment. This is the first report, to our knowledge, of synovial sarcoma associated with XY GD.

Keywords: Gonadal dysgenesis; dysgerminoma; gonadoblastoma embryonal carcinoma.; synovial sarcoma.

Figure 1. A huge mass with internal cystic components and calcifications, within the cul de sac. Note that the bladder and uterus are displaced anteriorly and the rectum is displaced posteriorly by the lesion (A). Another lesion with calcifications. A small cyst is also visible at the upper level (B), retroperitoneal lymphadenopathy with mild compression on the left renal vein (C). Axial computed tomography image at the renal sinus level shows a huge mass with irregular borders and heterogeneous enhancement within the left retroperitoneal localization, anterior to the left kidney (D). A hypo dense mass with mild irregular contours in the right abdomen at the posterolateral aspect of the caecum and ascending colon (E)

Figure 2. The growth of the gonadoblastoma occurred as rounded nests separated by fibrous stroma that contained significant calcification (hematoxylen and eosin, x40) (A). The germ cells, similar to dysgerminoma cells, in the gonadoblastoma (hematoxylen and eosin, x200) (B). Dysgerminoma. Nests of dysgerminoma cells were separated by fibrous septa containing lymphocytes and plasma cells. The tumor cells had round vesicular nuclei with prominent nucleoli and abundant pale cytoplasm (hematoxylen and eosin, x400) (C). Gonadoblastoma was detected within the streak ovary. The tumor contained a nest of predominantly sex cord-like cells distributed around hyalinized acini (arrow) (hematoxylen and eosin, x400) (D). Synovial sarcoma (monophasic component). Sheets of uniform small spindle cells with ovoid nuclei and scanty cytoplasm (hematoxylen and eosin, x200) (E)