A 10 year old boy has a small tumor in the wall of the right lateral ventricle. A biopsy of this tumor is consistent with subependymal giant cell astrocytoma. Which of the following lesions may also be present in this patient?

This item tests your knowledge of neurocutaneous syndromes, a group of hereditary conditions characterized by concomitant neoplastic or hamaomatous lesions predominantly affecting the skin and nervous system. Subependymal giant cell astrocytoma is a peculiar astrocytic tumor that grows from the walls of the lateral ventricles. It is pathognomonic of tuberous sclerosis, which is caused by mutations of TS1 or TS2 genes. Tuberous sclerosis manifests with multiple hamaomatous lesions in the skin, CNS, and visceral organs. Coical tubers are malformed (hamaomatous) nodules of the coex, probably resulting from faulty coical development. Other lesions include shagreen patches and ash-leaf spots on the skin, cardiac myxomas, and renal angiomyolipomas. Cafe-au-lait spots are found in both types of neurofibromatosis. Lisch nodules are small pigmented nodular lesions of hamaomatous nature that are present in the iris of patients with neurofibromatosis type 1. Hemangioblastoma is a vascular tumor of unknown histologic origin that frequently develops in the cerebellum of patients with von Hippel-Lindau syndrome. Renal cell carcinomas are also common in this disease. Von Hippel-Lindau syndrome is caused by autosomal dominant mutations of the VHL gene, a tumor suppressor gene. You may recall that mutations of VHL gene are also found in the majority of sporadic renal cell carcinomas. Ref: Bernard T.J., Knupp K., Yang M.L., Kedia S., Levisohn P.M., Moe P.G. (2012). Chapter 25. Neurologic & Muscular Disorders. In W.W. Hay, Jr., M.J. Levin, R.R. Deterding, J.J. Ross, J.M. Sondheimer (Eds), CURRENT Diagnosis & Treatment: Pediatrics, 21e.