Abstract

BACKGROUND AND DESIGN:

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).

CONCLUSION:

Our findings indicate that chronic, very-low-dose isotretinoin can induce hyperostotic axial skeletal changes similar to those reported in patients taking higher doses.