Regression of a cardiac rhabdomyoma in a patient receiving everolimus.

Tuberous sclerosis complex (TSC) is an autosomal dominant neurocutaneous disorder that can affect every organ of the body, most commonly the brain, kidneys, heart, and lungs. The TSC mutation results in abnormal cellular proliferation and differentiation, which are responsible for hamartomatous lesions that affect the brain, kidney, heart, and lungs. mTOR (mammalian target of rapamycin) is a protein kinase that regulates the abnormal cellular proliferation and differentiation. Consequently, mTOR inhibitors are being studied to treat the subependymal giant-cell astrocytomas and renal angiomyolipomas that are commonly seen with TSC. We describe here the case of a patient with significant regression of a cardiac rhabdomyoma after receiving everolimus, an mTOR inhibitor. This finding suggests a possible novel therapy for patients with clinically significant cardiac rhabdomyomas.