Efficacy and safety of lanreotide in Korean patients with metastatic, well-differentiated gastroenteropancreatic-neuroendocrine tumors: a retrospective analysis

Lanreotide autogel is a long-acting somatostatin analogue with proven efficacy and safety in patients with well-differentiated (WD) gastroenteropancreatic-neuroendocrine tumors (GEP-NETs) in a prior randomized phase III trial (CLARINET). However, the CLARINET study only enrolled patients with Ki-67 index <10%, and few patients of Asian ethnicity were included. We retrospectively analyzed the efficacy and safety of lanreotide in Korean patients with GEP-NETs in the daily practice setting. Between January 2015 and May 2018, 64 patients with metastatic WD GEP-NETs received lanreotide at Asan Medical Center, Seoul, Korea. Of them, 45 (70.3%) patients who received lanreotide as monotherapy were included in the current analysis. The most common primary tumor site was the pancreas (n = 22, 48.9%), followed by the rectum (10, 22.2%) and the small bowel (7, 15.6%). According to RECIST v1.1, a partial response was achieved in one patient (2.2%) and stable disease was achieved in 40 patients (88.9%). The median progression-free survival (PFS) was 16.4 months (95% confidence interval, 9.5–23.3 months). There were no differences in PFS according to the primary tumor site (p = 0.77). Hepatic tumor volume > 25% and prior systemic therapy were significantly associated with poorer PFS in the multivariate analysis. Lanreotide is well-tolerated and effective for Korean patients with GEP-NETs in the daily practice setting.