Primary occipital myxoma: A rare case report
A 12-year-old male had 2-month history of mild occipital headache which was unnoticed. Local hairdresser noticed a slight bulge in the occipital region while doing haircut. He reported this to the parents to seek medical advice. His MRI and CT brain showed evidence of a 5.3 × 4.6 × 4.9 cm expansile lytic sclerotic lesion arising from the right occipital bone showing prominent trabecular pattern. No significant soft tissue component or enhancement was seen. Anteriorly the lesion was causing significant indentation of the right cerebellar hemisphere. There was no edema but it was producing erosion of the right half of occipital bone extending up to C1 vertebra []. The diagnosis suggested was a malignant bone neoplasm (Ewing sarcoma) or intraosseus hemangioma. A craniotomy with near total excision of the mass was done leaving residual mass near the vertebral artery.\nMultiple small bony and soft tissue pieces with a slimy surface were submitted for histopathology. Sections after decalcification showed bone and tumor cells. Stellate cells with abundant myxoid matrix with few cells showing pleomorphic nuclei and few tumor giant cells were also seen. Histological diagnosis of fibromyxoid tumor [] was made and immunohistochemical markers were advised.\nOn immunohistochemistry the tumor cells expressed Vimentin []. They were immunonegative for SMA, Desmin, CD34, S-100, EMA, CK, CD31, and GFAP. The Mib-1 proliferation was <1%. Final diagnosis of myxoma with stromal atypia was made. 2D-echocardiography was done to search for primary but there was no mass lesion in the cardiac muscles. Postoperative radiotherapy for the residual lesion was started two weeks after wound healing and a total of 50.4 Gy in 28 fractions to tumor bed was given on linear accelerator. Mean dose to the brain stem was 1237 cGy. Post-radiotherapy CT Scan showed minimal edema and no residual disease [].