Treatment Decision-Making for Neuroendocrine Tumors

First-Line Treatment Data and Somatostatin Analogs

The foundational decision in management of neuroendocrine tumors (NETs) involves determining whether immediate treatment is necessary or whether observation is appropriate. For patients requiring treatment, somatostatin analogs represent the standard first-line approach based on robust clinical trial data. The PROMID trial demonstrated clear progression-free survival benefits for octreotide compared with placebo, while the CLARINET trial showed similar benefits for lanreotide, both in well-differentiated, low-grade tumors.

These pivotal trials included primarily gastroenteropancreatic NETs with low Ki-67 indices, establishing somatostatin analogs as preferred therapy for indolent, slowly progressive disease. While recent data suggest potential benefits for up-front PRRT, the lack of overall survival data keeps this approach developmental rather than standard practice. Treatment selection must consider somatostatin receptor expression, as receptor-negative tumors (common in lung primaries) may not benefit from analog therapy.

For highly symptomatic, high-burden disease, somatostatin analog monotherapy may prove insufficient, requiring combination approaches or alternative strategies. The presence of adequate somatostatin receptor expression remains fundamental, with both uptake intensity and receptor distribution influencing treatment decisions. Current practice generally favors somatostatin analogs for low-volume, low-progression-rate tumors while reserving more aggressive approaches for symptomatic or rapidly progressive disease.