PRL and neoplasm: Given that the 2022 WHO classification recommends categorizing PitNETs on the basis of pituitary TFs combined with classical pituitary hormones and the cutoff of 10% for PRL positive cells favors the diagnosis of somatolactotroph tumors (36), we consider the PIT1 tumor to be a GH/PRL positive tumor when more than 10% of cells are positive for PRL by IHC.