Insulinoma and Tuberous Sclerosis: A Possible Mechanistic Target of Rapamycin (mTOR) Pathway Abnormality?

A 23-year-old New Zealand Māori male with tuberous sclerosis (TSC) and associated neurocognitive abnormalities presented with altered behavior and increasing seizure frequency. Endogenous hyperinsulinemia from an underlying insulinoma was confirmed and this was managed surgically. This case represents only the sixth description of insulinoma in TSC to date. The role of the hamartin–tuberin complex in regulation of the mechanistic target of rapamycin pathway provides a plausible pathogenetic mechanism between insulinoma and TSC. This rare disease association should be considered in TSC patients who present with otherwise unexplained worsening neurocognitive symptoms.