Pagetoid dyskeratosis with a palmar localization: Rapid resolution following biopsy.

Background: Pagetoid dyskeratosis (PD), which is found in more than 2% of skin biopsy specimens, is accepted as a histopathological finding reflecting the abnormal keratinization process. However, to date, only a limited number of cases have been described to have brown pigmentation on the hands, triggered by friction, and present with pagetoid dyskeratosis as the only sign on histopathology and a parallel ridge pattern on dermoscopy.

Aim: To present and discuss the typical clinical, histopathological, and dermoscopic features of pagetoid dyskeratosis, and to draw attention to the spontaneous resolution following biopsy.

Patient: We present a case of pagetoid dyskeratosis with a palmar localization, which rapidly resolved following biopsy, in a patient with no history of friction.

Results: PD is the only important histopathological finding in typical irregular pigmented lesions located in the hand. PD should also be considered in the differential diagnosis of lesions that show parallel ridge pattern on the hand. Two weeks after the biopsy, disappearance of the lesion may be due to the effect of inflammatory response revealed by biopsy.

Conclusions: Although the cause of this condition is not yet fully understood, most cases being associated with friction or rapid spontaneous resolution following biopsy, as in the current case, may indicate the reactive nature of the lesion. Further researches are required to be clarify etiology of PD.