Sclerosing stromal tumor of the ovary associated with benign endometrioid peritoneal implants

Sir, We report a case of sclerosing stromal tumor (SST) of the ovary, a rare benign tumor seen in young females and its association with benign endometrioid peritoneal implants. A 19-year-old unmarried girl presented to the gynaecology outpatient department, with complaints of pain and lump in the abdomen, for one month. There was no history of menstrual disturbances or signs of virilization. On examination, there was a mass in the abdomen arising from the pelvis. Per-rectal examination revealed a mass about 10-11 cm in diameter in the right fornix. Ultrasonography (USG) of the pelvis revealed that the uterus was pushed to the left by a right adnexal mass 11.9 x 9.7 cm in size. The left ovary was normal. Right salpingo-oophorectomy with omental biopsy was done for surgical staging. The postoperative period was uneventful. Grossly : Two specimens were received: (1) A bisected half of the tumor mass measuring 9 x 7 x 3cm was received. Outer surface was unremarkable. Cut surface showed grey-white areas intermingled with gelatinous areas, and focal area of congestion. Several blocks were studied from different areas of the tumor. (2) A 2.5-cm long piece of omentum was received, which was normal on gross examination. The tumor showed hypercellular areas. The hypercellular foci revealed pseudolobular architecture, comprising spindle fibroblastic cells, admixed with large vacuolated rounded cells. The pseudolobules were separated by areas of dense fibrocollagenous tissue and edematous connective tissue. Prominent, ectatic, thin-walled vessels were distributed within the pseudolobules and in the surrounding tissue [Figure 1] Reticulin stain showed the presence of reticulin fibers encircling individual tumor cells in the cellular areas. Abundant reticulin fibers were also seen in the sclerotic areas. Omental biopsy showed mesothelial hyperplasia and foci of benign endometrial glands without stroma, marked chronic inflammatory cell infiltration and vascular congestion [Figure 2]. A diagnosis of sclerosing stromal tumor with benign endometrioid peritoneal implants was made. SSTs of the ovary are benign tumors of the thecoma-fibroma group, and they do not metastasize. The clinical and microscopic features of our case were similar to those as first described by Chalvardjian and Scully,[] and other cases reported in the literature. Benign endometrioid peritoneal implants have been reported in association with borderline ovarian endometrioid tumors. They are thought to arise directly from the peritoneum or may represent foci of endometriosis in which stroma is atrophied.[] They can create a diagnostic difficulty with metastatic carcinoma of the ovary but the benign epithelium of the endometrioid implant and the lack of stromal invasion are the key features in deciding its benign nature. The present case is being reported since we came across a rare finding of benign endometrioid implants in the omentum, along with sclerosing stromal tumor of the ovary. REFERENCES - 1. Chalvardjian A, Scully RE. Sclerosing stromal tumors of the ovary Cancer. 1973;31:664–70 - 2. Clement PB. Diseases of Peritoneum Blaustein's Pathology of the female genital tract. 20025 th Springer Verlag:768