Endocrine Abstracts

Purpose: The efficacy and safety of RAD, an mTOR inhibitor, in patients with well differentiated metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NET).

Material and methods: We studied seven male patients (mean age 55 years, range 36–75) with well differentiated non functioning stage IV GEP-NETs (five pancreatic, one hindgut carcinoid, and one NET of unknown primary). All received RAD 10 mg/day in combination with long acting octerotide 30 mg/month. Five patients had progressive disease despite previous treatment (three chemotherapy, two radiolabelled somatostatin analogues), while RAD was the initial treatment for two patients. The efficacy of treatment was evaluated with biochemical (chromogranin A, CgA) and radiological (RECIST) criteria.

Results: The mean time of follow up was 7.8 months (range 2.7–19). Using RECIST criteria, five patients showed stable disease (three with previous progressive disease) and two patients showed progression (both with previously documented progressive disease). The mean value of CgA before RAD treatment was 149.14 ng/ml (range 63–242), and 181 ng/ml (range 66–345) after last assessment; four patients had biochemically stable disease. Four patients developed grade I aphthodous stomatitis, two grade I rash, and two grade I diarrhea. Hyperglycemia was observed in all of them (four grade I, three grade II), and hyperlipidemia in six. Anemia developed in four patients (three grade I, one grade II), grade I thrombocytopenia in one, and leucocytopenia in three (two grade I, one grade II). No patient discontinued RAD treatment because of a serious adverse event.

Conclusion: Although the time of follow up is relatively short, the administration of 10 mg everolimus orally in combination with octreotide is a well tolerated and efficient treatment, in patients with well differentiated metastatic GEP-NETs with documented progression before treatment.