AVP and small cell lung carcinoma: Gniazdowska et al. investigated the conjugation of vasopressin (AVP) (CYFQNCPRG) and its analogue (d(CH2)5[D-Tyr(Et2), Ile4, Eda9 ]AVP (AVP(an)) to technetium-99m radionuclide to test its potential as a diagnostic radiopharmaceutical for SCLC patients [257].