Treatments with 100nM OCT (three tumor samples) or PAS (four tumor samples) caused a significant ACTH reduction in two out of three tumors in the presence of high OCT concentrations, while only a slight ACTH reduction in two out of four samples was observed with PAS, despite a prevalent expression of SST5 mRNA in all samples as compared to SST2 mRNA. Here, SSTR5 is linked to neoplasm.