Endocrine Abstracts

Temozolomide, an alkylating agent used in malignant gliomas, has been recently used too in the treatment of aggressive pituitary tumors. To date, two cases of Nelson’s syndrome has successfully treated with 5 days of 28-day cycle, but the follow-up has been shorter than 12 months. We reported the third patient with Nelson’s syndrome treated with temozolomide, who after an initial goal response to three 300 mg 5 days of 28-day cycles shown a clinical and biochemical (ACTH) escape which was controlled changing the temozolomide regimen to 120–140 mg on alternate days.

Patient: A 55-year-old man presented in 2002 with Cushing’s syndrome. Magnetic resonance imaging (MRI) scan revealed an intrasellar mass that infiltrates right cavernous sinus. Fourteen months after an initial disease control with transsphenoidal pituitary surgery and postoperative stereotactic radiotherapy, the patient had a recurrence and bilateral adrenalectomy was performed. Six months afterwards he had headaches and right third cranial nerve palsy. The MRI scan revealed a 2.5 cm pituitary tumor with large right cavernous sinus invasion reflecting a Nelson’s syndrome. The lesion was treated with tomotherapy with an initial good disease control, lost 17 months after. 2 mg/week Cabergoline was initiated with partial response so temozolomide 300 mg 5 days of 28-day cycles was added initially and after 3 months changed to 120–140 mg on alternate days. The evolution of plasma ACTH levels is resumed in the table. MRI control showed no increase of the tumor during 8 months of follow-up. Astenia has been the main adverse event.

Conclusions: The daily temozolomide therapy can be an alternative effective to 5 days of 28-day cycle regimen when ACTH escape occurs.