Case study: world’s largest renal myopericytoma—management and literature review

Renal myopericytoma is a rare renal mesenchymal neoplasm. It is primarily benign with limited clinical research, which makes its diagnosis a challenge. Till date, only 13 cases have been reported in literature. In this study, we report one of the largest renal myopericytomas. A young male with a large palpable renal mass diagnosed by contrast-enhanced computed tomography (CECT) of the abdomen and positron emission tomography (PET)-CT underwent right radical nephrectomy. The resected mass was in the size of 40 × 30 × 25 cm and weighed 12.6 kg. A diagnosis of renal myopericytoma was made on histopathologic examination after ruling out histopathologic mimics using a wide panel of immunohistochemical markers. The patient is free of recurrence at 21 months of follow-up. The rare location, unusually large size, and prominent myxoid change make it a rare entity. Its large size does not correlate with its malignant potential. Surgical excision is curative.