Symptom Diaries of Patients with Midgut Neuroendocrine Tumors Treated with ¹⁷⁷Lu-DOTATATE

We report the impact of ¹⁷⁷Lu-DOTATATE treatment on abdominal pain, diarrhea, and flushing, symptoms that patients with advanced midgut neuroendocrine tumors often find burdensome. Methods: All patients enrolled in the international randomized phase 3 Neuroendocrine Tumors Therapy (NETTER-1) trial (¹⁷⁷Lu-DOTATATE plus standard-dose octreotide long-acting repeatable [LAR], n = 117; high-dose octreotide LAR, n = 114) were asked to record the occurrence of predefined symptoms in a daily diary. Change from baseline in symptom scores (mean number of days with a symptom) was analyzed using a mixed model for repeated measures. Results: Patients (intent-to-treat) who received ¹⁷⁷Lu-DOTATATE experienced a significantly greater decline from baseline in symptom scores than patients who received high-dose octreotide LAR. For ¹⁷⁷Lu-DOTATATE, the mean decline in days with abdominal pain, diarrhea, and flushing was 4.10, 4.55, and 4.52 d per 4 wk, respectively, compared with 0.99, 1.44, and 2.54 d for high-dose octreotide LAR. The mean differences were 3.11 d (95% CI, 1.35-4.88; P = 0.0007) for abdominal pain, 3.11 d (1.18-5.04; P = 0.0017) for diarrhea, and 1.98 d (0.08-3.88; P = 0.0413) for flushing, favoring ¹⁷⁷Lu-DOTATATE. A positive repeated-measures correlation was found between diary-recorded symptom scores and questionnaire-recorded pain, diarrhea, and flushing. Conclusion: In addition to efficacy and quality-of-life benefits, symptom diaries from NETTER-1 demonstrated that treatment with ¹⁷⁷Lu-DOTATATE was associated with statistically significant reductions in abdominal pain, diarrhea, and flushing, constituting the core symptoms of patients with progressive midgut neuroendocrine tumors, compared with high-dose octreotide LAR, supporting a beneficial effect of ¹⁷⁷Lu-DOTATATE on health-related quality of life.