PURPOSE: To explore the possible involvement of adrenomedullin in the pathophysiology of intraocular and orbital tumors. METHODS: Competitive reverse transcription-polymerase chain reaction was used to determine adrenomedullin mRNA levels in the tissues from 40 consecutive patients (40 eyes) undergoing vitrectomy, orbital tissue biopsy, or enucleation for various ocular diseases, including intraocular (n = 4) and orbital (n = 3) tumors, proliferative vitreoretinopathy (n = 8), proliferative diabetic retinopathy (n = 8), age-related macular degeneration (n = 4), preretinal macular fibrosis (n = 9), and acute retinal necrosis (n = 4). RESULTS: Adrenomedullin mRNA levels in the tissues obtained from patients with intraocular or orbital tumors were significantly higher than those of patients with proliferative vitreoretinopathy (P < .05), proliferative diabetic retinopathy (P < .05), preretinal macular fibrosis (P < .005), and acute retinal necrosis (P < .01). CONCLUSION: Adrenomedullin may play a role in the pathophysiology of intraocular and orbital tumors. Copyright (C) 2000 Elsevier Science Inc.