title: Skeletal hyperostosis in patients receiving chronic, very-low-dose isotretinoin.
abstract: METHODS
  We conducted a prospective roentgenographic survey of patients participating in a randomized, placebo-controlled, multicenter clinical trial that evaluated the effectiveness of chronic, very-low-dose (approximately 0.14 mg/kg per day for 3 years) isotretinoin in preventing the subsequent occurrences of new basal cell carcinoma in patients with previous basal cell carcinoma. To assess potential skeletal changes, a sample of 269 patients from among a total of 981 enrollees were randomly selected for comparative roentgenographic review. Baseline and 36-month roentgenograms of the cervical and thoracic spine of each patient were read side by side by a radiologist, masked to treatment group, who noted both the presence and extent of abnormalities at each vertebral level at baseline and the progression of existing or occurrence of new abnormalities at previously unaffected levels at 36 months.
  
  
  RESULTS
  In comparison with the placebo group, significantly more patients in the isotretinoin group exhibited progression of existing hyperostotic abnormalities (40% vs 18%; P less than .001) and new hyperostotic involvement at previously unaffected vertebral levels (8% vs 1%; P = .015).
  
  
  CONCLUSIONS
  Our findings indicate that chronic, very-low-dose isotretinoin can induce hyperostotic axial skeletal changes similar to those reported in patients taking higher doses.
authors.affiliation: Division of Cancer Prevention and Control, National Cancer Institute, National Institutes of Health, Bethesda, Md.
authors.forename: J A
authors.initials: JA
authors.lastname: Tangrea
authors.forename: R F
authors.initials: RF
authors.lastname: Kilcoyne
authors.forename: P R
authors.initials: PR
authors.lastname: Taylor
authors.forename: W E
authors.initials: WE
authors.lastname: Helsel
authors.forename: M E
authors.initials: ME
authors.lastname: Adrianza
authors.forename: A M
authors.initials: AM
authors.lastname: Hartman
authors.forename: B K
authors.initials: BK
authors.lastname: Edwards
authors.forename: G L
authors.initials: GL
authors.lastname: Peck
mesh_terms: D000328:Adult; D000368:Aged; D002280:Basal Cell Carcinoma / Q000517:prevention & control; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D004057:Hyperostosis, Diffuse Idiopathic Skeletal / Q000139:chemically induced* / Q000000981:diagnostic imaging; D015474:Isotretinoin / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D011446:Prospective Studies; D011859:Radiography; D012878:Skin Neoplasms / Q000517:prevention & control; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging
chemical_list: D015474:Isotretinoin