Peptide receptor radionuclide therapy with 177Lu-octreotate in patients with foregut carcinoid tumours of bronchial, gastric and thymic origin

Abstract
Purpose Foregut carcinoid tumours have a different embryological origin than other gastroenteropancreatic neuroendocrine tumours (GEP NETs). In the total group of GEP NETs (n = 131), treatment with 177Lu-octreotate resulted in tumour remission in 47% of patients, with a median time to progression (TTP) of >36 months. As patients with foregut carcinoids may respond differently, we here present the effects of this treatment in a subgroup of patients with foregut carcinoids of bronchial, gastric or thymic origin. Methods Nine patients with bronchial, five with gastric and two with thymic carcinoids were treated. All patients had metastasised disease. The intended cumulative dose of 177Lu-octreotate was 22.2–29.6 GBq. Southwest Oncology Group criteria were used for response evaluation. Results Bronchial carcinoids: Five patients had partial remission, one had minor response (MR, tumour size reduction: ≥25%, Gastric carcinoids: One patient had complete remission, one had MR and two had SD, including one with PD at baseline. One patient developed PD. Thymic carcinoids: One patient had SD. In the other patient, disease remained progressive. All patients: Overall remission rate was 50%, including MR. Conclusion 177Lu-octreotate treatment can be effective in patients with bronchial and gastric carcinoids. Its role in thymic carcinoids cannot be determined yet because of the limited number of patients. The overall remission rate of 50% in patients with the studied foregut carcinoids is comparable to that in the total group of GEP NETs.