SSTR2 and neuroendocrine neoplasm: This hypothesis was studied in NPC cells in which SSTR2 agonists (lanreotide, octreotide, and PEN-221) were evaluated as investigational treatment strategies Octreotide and lanreotide did not affect NPC tumor proliferation, different to what has been observed in more indolent neuroendocrine tumors; however, PEN-221 did demonstrate an increase in OS and anti-tumor efficacy.