title: Adenoma of the iris pigment epithelium: a report of 20 cases: the 1998 Pan-American Lecture.
abstract: BACKGROUND
  Adenoma of the iris pigment epithelium (IPE) is an uncommon lesion that can simulate iris or ciliary body melanoma, melanocytoma, and pigment epithelial cyst.
  
  
  OBJECTIVE
  To evaluate the clinical and pathological features and prognosis of adenoma of the IPE in patients managed by us and to elucidate the features that help to differentiate this tumor from iris melanoma and other similar conditions.
  
  
  METHODS
  The medical records of 20 patients with adenoma of the IPE were reviewed, and the clinical and histopathologic features were tabulated.
  
  
  RESULTS
  Ten patients were male and 10 were female, with a mean age of 60.0 years (range, 11-85 years). All patients were referred because of suspected iris or ciliary body melanoma. All lesions were solitary and unilateral. Sixteen were located in the peripheral iris; 2, in the midzone; and 2, near the pupillary margin. Clinically, all tumors were abruptly elevated, all but 1 were dark gray to black, and all had a smooth, but sometimes multinodular, surface. The tumors caused thinning or complete effacement of the overlying iris stroma, but they did not directly involve the stroma. They typically blocked light with transillumination. On ultrasound biomicroscopy findings, adenoma of the IPE shows a solid tumor pattern, sometimes with small cystoid spaces. The tumor was managed by local resection in 2 patients and observation in 18, all of whom have been stable, with follow-up ranging from 6 months to 9 years. Histopathologic examination revealed a tumor originating in the IPE consisting of cords of pigment epithelial cells separated by septae of connective tissue.
  
  
  CONCLUSIONS
  Adenoma of the IPE usually has characteristic features that should differentiate it from iris melanoma, ciliary body melanoma, iris melanocytoma, and iris cyst. Adenoma of the IPE is a benign tumor that may remain relatively stable for years.
authors.affiliation: Oncology Service, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pa 19107, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Shields
authors.forename: C L
authors.initials: CL
authors.lastname: Shields
authors.forename: G
authors.initials: G
authors.lastname: Mercado
authors.forename: K
authors.initials: K
authors.lastname: Gündüz
authors.forename: R C
authors.initials: RC
authors.lastname: Eagle
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000869:Anterior Eye Segment / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015811:Iris Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010857:Pigment Epithelium of Eye / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D011379:Prognosis; D014463:Ultrasonography