Immunohistochemical localization of cytokeratins and involucrin in calcifying epithelioma: comparative studies with normal skin

The study investigated the immunohistochemical distribution of cytokeratins and involucrin in calcifying epithelioma of Malherbe, comparing it with normal skin to understand the tumor's nature and differentiation. It found that the tumor cells differentiated into both the hair cortex and outer root sheath, with basophilic cells showing similar staining patterns to the outermost cell layer of the outer root sheath in hair follicles. This supported the hypothesis that keratinocytes in this layer could differentiate into the transitional portion of the follicle and anagen hair.