SSTR5 and neoplasm: Actually, in somatotropinomas, although the complete set of factors defining SSA responsiveness is not yet fully defined, various specific tumor features and molecular markers have been shown to relevantly influence tumor response to SSAs, including granulation pattern, AIP and GNAS mutations, β‐arrestin, filamin A, and E‐cadherin expression, as well as, interestingly, SSTR2/SSTR5 expression balance and SST5TMD4 presence [13, 16, 33, 34].