Nonlipidized juvenile xanthogranuloma: An unusual variant with a potential diagnostic pitfall

Oral juvenile xanthogranuloma in a child: Clinical, histological and immunohistochemical profile of a rare entity

“…Most of lesional cells were negative for S‐100 and CD1a, ruling out LCH. Immunostaining for factor XIIIa was described focally in classic JXG and diffusely in nonlipidized JXG, and it was suggested that this marker indicates a cellular type derived from dendritic cells, which would be more prominent in nonlipidized JXG; however, in our case the expression of factor XIIIa was intense and diffuse in practically all the lesional cells similar to the case reported by Consolaro et al In addition, the positivity for factor XIIIa, CD10 and focal CD34 in the present case, may be explained by the expression of these markers in several neoplasms, including fibrohistiocytic tumors . Ki‐67 index was low (3%), although superficial areas showed an intermediate proliferation index (10%) a finding which must not be erroneously interpreted as indicator of malignancy …”

“…However, there are other less frequent clinicopathologic variants of JXG such as nonlipidized and mononuclear variants, which could even be confused with a malignant mesenchymal neoplasm. The mononuclear JXG, presents vacuolar foamy histocytes in the absence of giant cells, and because of this feature, it may be misdiagnosed as LCH, melanoma or balloon cell nevus . In these cases, a careful clinical evaluation, histopathological analysis and immunohistochemistry are needed to make a correct diagnosis.…”

“…In most of the cases the lesions tend to flatten with time and regress spontaneously within a period of 3 to 6 years. Due to its benign and self‐limiting nature, this disorder is considered to be a reactive rather than a neoplastic process, although, the pathogenesis remains unknown …”

Coexistence of Classic and a Mononuclear Variant of Juvenile Xanthogranuloma in an Adult Patient

“…Juvenile xanthogranuloma (JXG) is histologically characterized by dense mononuclear cells with foamy histiocytes and Touton giant cells in a background of lymphocytes and eosinophils 1 2 3 . An unusual variant of non-lipidized JXG has been described in approximately 28 cases, in which Touton giant cells and foam cells are absent or very scant.…”

“…An unusual variant of non-lipidized JXG has been described in approximately 28 cases, in which Touton giant cells and foam cells are absent or very scant. These cases are described as non-lipidized JXG, early JXG, or a mononuclear JXG variant 1 3 4 5 . This variant is typically found in infants or children younger than three years and presents most commonly as a solitary lesion 1 4 .…”