Insulinoma in a patient with tuberous sclerosis: is there an association?

OBJECTIVE

To describe a patient with tuberous sclerosis who, on initial assessment, had neurologic symptoms, which were ultimately found to be caused by an insulinoma.

METHODS

We present a case report with clinical, laboratory, and radiologic data. The literature is reviewed relative to tuberous sclerosis and islet cell tumors, and a possible association is discussed.

RESULTS

A 43-year-old man with a history of tuberous sclerosis required medical attention because of mental confusion and slurred speech and was found to have hypoglycemia. Neuroradiologic imaging showed no new lesions to account for his symptoms. His physical examination was striking for a large abdominal mass, which showed increased uptake on octreotide scanning. After surgical resection, the mass measured 21 cm and was found to be an insulinoma. Blood glucose values were normal postoperatively and on follow-up, and the patient had no recurrence of the symptoms.

CONCLUSION

From this report, we emphasize two findings. First, we draw clinicians' attention to the possibility of an association between islet cell tumors and tuberous sclerosis and suggest consideration of this diagnosis in patients with tuberous sclerosis who have new or worsening neurologic symptoms. Second, the insulinoma we describe is, to our knowledge, the largest to be reported thus far in the literature.