皮膚科および皮膚科疾患ジャーナル

Diagnosis of pigmented lesions of the oral cavity is challenging. Oral pigmentation can be physiological or pathological, melanin-associated or non-melanin-associated, and endogenous or exogenous. Evaluation of a patient with oral pigmentation requires a systemic approach. This review presents diagnosis, differential diagnosis and management of pigmentary findings in the oral cavity.

Pagetoid dyskeratosis is a benign incidental pathologic finding. It clinically presents as a brownish macule, and histopathologic findings show pale cells resembling cells of Paget disease within the epidermis. Pagetoid dyskeratosis of the hand can mimic a malignant melanoma and should be included in the differential diagnosis of pigmented palmar lesions that show a parallel cutaneous ridge pattern on dermoscopy.

In recent years, the practice of decorative tattooing has seen rising popularity and increased social acceptance. As newer tattoo inks are developed and utilized, it is expected that the rate of reactions will rise. Thus, dermatologists are more likely to encounter tattoo-related complications. An understanding of the most common histopathologic reaction patterns ideally will result in increased clinical detection of situations requiring additional evaluation, whether it is for an underlying infection, systemic involvement of disease, or to rule out a cutaneous malignancy. This review will describe both the clinical and histopathologic features of pathologic reactions to decorative tattoos. The main histopathologic reactions are divided into six distinct categories: allergic hypersensitivity, granulomatous, interface, pseudolymphomatous, oncologic and infectious.