Peptide receptor radionuclide therapy with 177Lu-DOTATATE for symptomatic control of refractory carcinoid syndrome

CONTEXT: Peptide receptor radionuclide therapy (PRRT) with 177Lu-DOTATATE results in an increase of progression-free survival and quality of life in patients with progressive well-differentiated neuroendocrine neoplasms (NENs).OBJECTIVE: To study the effect of 177Lu-DOTATATE in patients with carcinoid syndrome and radiologically stable or newly diagnosed disease treated solely for the purpose of symptom reduction.DESIGN: Retrospective cohort study.SETTING: Tertiary care hospital.PATIENTS: 22 patients with a metastatic midgut NEN, elevated urinary 5-hydroxyindolacetic acid excretion and flushing and/or diarrhea despite treatment with a somatostatin analog, without documented disease progression.INTERVENTION: PRRT with 177Lu-DOTATATE (intended cumulative dose: 29.6 GBq) with a primary aim to reduce symptoms.RESULTS: After PRRT, mean bowel movement frequency (BMF) decreased from 6.1 ± 3.4 to 4.6 ± 3.6 per day (p=0.009). Flushes decreased from 4.3 ± 2.9 to 2.4 ± 2.7 flushes per day (p=0.002). A decrease of BMF of more than 30% occurred in 47% of patients with baseline BMF of 4 or more (n=17). In patients with ≥2 episodes of flushing a day (n=15), 67% of patients had more than 50% decrease of daily flushing. A decrease in urinary 5-hydroxyindolacetic acid excretion of more than 30% was seen in 56% of patients. The EORTC-C30 diarrhea subscale score showed a trend towards improvement by an average of 16.7 ± 33.3 points (p=0.11).CONCLUSION: PRRT with 177Lu-DOTATATE effectively reduced diarrhea and flushing in patients with carcinoid syndrome and can be considered for symptomatic treatment of carcinoid syndrome insufficiently controlled with somatostatin analogs.