Connective tissue nevi: An entity revisited

BackgroundConnective tissue nevi (CTN) may be isolated, either sporadic or hereditary, or syndromic as in the Buschke-Ollendorff syndrome. Few publications have addressed the variable clinical and histopathologic expression of these benign hamartomas.ObjectiveWe sought to characterize the clinical and histopathologic features of CTN and to highlight a spectrum of clinical disease.MethodsWe carried out a retrospective study of cases selected after strict clinical and histopathologic confirmation of the diagnosis.ResultsA total of 33 patients with CTN were included. The average age of onset was 2 years. Three clinical forms were distinguished: type A with lesions at a single site, with one case presenting as an ulcerated infiltrated plaque; type B with two or more sites of involvement; and type C with unusually severe infiltration with functional impairment of a limb. Histopathologic examination of lesional biopsy specimens showed 10 collagenomas, one elastoma, 18 mixed CTN, and an increased number of fibroblasts in 4 cases. No correlation between clinical type and histopathologic findings was observed.LimitationThis was a descriptive case series.ConclusionsCTN comprise a clinical spectrum ranging from isolated papules to unusually severe aggressive plaques with monomelic involvement. The histopathologic features are heterogeneous and include a newly described variant, which we name “cellular CTN” because of the increased number of fibroblasts.