Somatostatin analogues can specificially bind with somatostatin receptor(SSTR)which is usually over-expressed on many tumor cells.So it may have important significance to use 18F labeled somatostatin analogues as the tumor probes for the diagnosis of SSTR positive tumor.In order to explore a novel PET probe for the diagnosis of SSTR positive tumors,the Lys([Al18F]NOTA)-TOCA was Somatostatin analogues can specifically associated with somatostatin receptor (SSTR) which is usually over-expressed on many tumor cells. So it may have important significance to use 18F labeled somatostatin analogues as the tumor probes for the diagnosis of SSTR positive tumor. a novel PET probe for the diagnosis of SSTR positive tumors, the Lys ([Al18F] NOTA) -TOCA was