Partial spontaneous regression of Bowen's disease

Background: Although the lesions of Bowen's disease often show conspicuously irregular configurations, there have been no studies performed to elucidate what these clinical features imply. Of 90 patients with Bowen's disease, 34 (group 1) had such irregular lesions with patches of normal-appearing interlesional skin. Their clinical backgrounds were compared with those of 56 patients without irregular lesions (group 2). Specimens of lesional, in terlesional, and perilesional skin from the 17 patients in group 1 were examined to evaluate the histopathologic evidences of regression. Observations: The lesions of group 1 patients were more commonly located on the trunk, larger in size, and of longer duration than those of group 2 patients. The specimens of lesional skin from the 17 group 1 patients revealed amyloid deposition (12 patients), melanophages (three patients), increased vascularity (15 patients), and inflammatory cell infiltrates (17 patients). The interlesional skin also exhibited amyloid deposition (12 patients), melanophages (six patients), increased vascularity (15 patients), dermal fibrosis (16 patients), inflammatory cell infiltrates (15 patients), and epidermal atrophy (eight patients). The perilesional skin showed no amyloid depositions, melanophages, or increased vascularity. Conclusion: These histopathologic findings in normal-appearing interlesional skin may represent partial spontaneous regression of Bowen's disease.