Partial unilateral lentiginosis: a clinicopathological analysis of 32 cases on the head and neck area in Korea

BACKGROUND

Partial unilateral lentiginosis (PUL) is a rare acquired circumscribed hyperpigmentation characterized by multiple simple lentigines involving half of the body. Since the previous studies of PUL were mostly based on case reports and the current literature lacks well-designed retrospective studies that involve a large number of cases, PUL is not a well-defined entity, and differential diagnosis with nevus spilus is still difficult. This study aims to evaluate clinical and histopathological characteristics and treatment outcomes of PUL on head and neck area of Koreans.

METHODS

Thirty-two patients with PUL on head and neck area were diagnosed clinicohistopathologically at the Asan Medical Center from 2004 to 2017. Their medical records, photographs, and biopsy specimens were reviewed, and immunohistochemical staining for protein kinase C (PKC)-βΙΙ was evaluated for melanogenic activity.

RESULTS

Four patients (12.5%) of PUL had congenital lesions, and 24 (75.0%) had age of onset younger than 10 years. Confluency of lentiginous lesions (100%) and mild to moderate background interlesional hyperpigmentation (90.6%) were observed. The lentiginous lesions showed increased melanocytes, melanophages, basal melanins, lentiginous hyperplasia, and perivascular inflammatory cells compared with background interlesional hyperpigmentation, and PKC-βΙΙ was focally positive in 7 of 12 stained PUL lesions. Among the 16 patients who received laser treatments, 10 (62.5%) showed more than 50% of improvement.

CONCLUSIONS

The findings of this study will allow for improved diagnosis of PUL and understanding of its features, which may facilitate proper management in the future.

Synchronous melanomas arising within nevus spilus

Nevus spilus is a melanocytic cutaneous lesion consisting of a light brown background macule with numerous superimposed darker maculopapular speckles. Melanoma arising from a nevus spilus is rare, with less than 40 cases reported to date. The absolute risk for malignant transformation is not well defined, lacking a standardized management approach. We report a new case of melanoma arising from nevus spilus, with the additional peculiarity of multifocality. We offer our recommendations for the management of the condition.

Nevus Spilus (Speckled Lentiginous Nevus) in the Oral Cavity: Report of a Case and Review of the Literature

The congenital melanocytic nevus is a pigmented melanocytic lesion that presents at birth or shortly thereafter. It is commonly described on the skin, usually on the trunk and extremities. Only five intraoral cases of congenital melanocytic nevi have been described in the English literature. A nevus spilus (speckled lentiginous nevus) is a clinical variant of congenital melanocytic nevus. The authors present the case of a 19-year-old male with an intraoral nevus spilus. The anterior mandibular gingiva exhibited multiple speckled, pigmented papules and macules on a thickened, hyperplastic macular background. Microscopic examination revealed characteristic morphologic features of intramucosal nevi extending into the deep portions of the submucosa. Although other authors have reported similar clinical presentation in the oral mucosa, no other case reports were found in the English literature classifying an intraoral congenital nevus as an intraoral nevus spilus. The sixth case of an intraoral congenital melanocytic nevus and the first case subclassified as an intraoral nevus spilus (speckled lentiginous nevus) is reported, with a review of the literature.