Multiple agminated acquired melanocytic nevi

Picosecond 532 nm Laser: An Optimal Device for the Reduction of Acquired Agminated Nevi

OBJECTIVES

Agminated nevi are rare, grouped lesions, which are confined to one anatomic area. Herein, we report a case of successful cosmetic treatment of bilateral, acquired agminated nevi with a picosecond 532 nm Nd:YAG laser device.

MATERIALS AND METHODS

Literature search was completed on acquired agminated nevi. A healthy 21-year-old woman presented with numerous, grouped 1-mm brown-to-dark brown macules in the axillae bilaterally. Biopsies revealed lentiginous junctional nevi with mild atypia, leading to the diagnosis of agminated nevi. She was referred for laser treatment to improve cosmetic appearance. Two different laser devices were utilized initially, a picosecond 532 nm Nd:YAG laser on the left axilla and a millisecond domain 532 nm laser on the right. Greater improvement was noted with the picosecond 532 nm device. Three additional treatments were completed with the picosecond laser with significant improvement in pigmentation of melanocytic nevi.

RESULTS

Various pigmented and melanocytic lesions have been noted to occur in an agminated pattern although their pathway of development remains unknown. While various devices have demonstrated efficacy for pigmented lesions, treatment of agminated nevi specifically is less reported or established. Our patient's presentation is novel because of the axillary location and bilateral distribution of multiple acquired agminated nevi, neither of which have been previously reported in the literature. We also report successful treatment utilizing a picosecond 532 nm laser. While laser can help improve the cosmetic appearance of pigmented lesions, most lasers do not remove all melanocytes, highlighting the need for close monitoring, as atypia and melanoma have been reported to develop in acquired agminated nevi.

CONCLUSION

Thus, we present a case of acquired agminated nevi in a novel bilateral distribution in a healthy female successfully treated with a picosecond 532 nm laser.

Agminated presentation of fusion-driven melanocytic neoplasms

BACKGROUND

The conventionally understood pathogenesis of agminated Spitz nevi includes a mosaic HRAS mutation followed by copy number gains in 11p. However, we have recently observed agminated presentations of fusion-driven melanocytic neoplasms.

METHODS

We retrieved cases from our database of benign fusion-induced melanocytic neoplasms with an agminated presentation. Both the primary lesion and the secondary lesion were sequenced. TERT-promoter mutational testing and the melanoma fluorescence in situ hybridization assay were also performed.

RESULTS

Three cases were included. Two had a PRKCA fusion (partners ATP2B4 and MPZL1) and one had a ZCCHC8::ROS1 fusion. None of the cases met morphologic or molecular criteria for malignancy. There was no evidence of tumor progression in secondary lesions. The same fusion was identified in the primary and secondary lesions. None of the patients developed evidence of nodal or systemic metastasis.

CONCLUSIONS

We present accumulating evidence that fusion-driven melanocytic neoplasms can present with an agminated presentation. The differential diagnosis of an agminated presentation versus a locally recurrent or potentially locally metastatic tumor is critical, and accurate diagnosis has significant prognostic and therapeutic consequences for the patient. As with HRAS mutations, fusion-driven melanocytic tumors may have an agminated presentation.

Atypical presentation of genital molluscum contagiosum mimicking genital warts

A man in his 20s with a history of unprotected sex with a commercial sex worker three months before presented with a solitary slowly-growing, well-defined, non-tender, oval, verrucous lesion on the mucosal aspect of his prepuce. Dermoscopy revealed a polylobular, pinkish-white, amorphous structure in the centre with a surrounding crown of vessels that did not cross the centre of the lobules, and histopathology showed keratinocytes containing intracytoplasmic faintly granular eosinophilic inclusions and peripherally-pushed nuclei. A diagnosis of agminated genital molluscum contagiosum was reached on the basis of the above findings. Molluscum contagiosum can present with several atypical morphologies mimicking other dermatoses. Agminated molluscum contagiosum can closely mimic a genital wart especially if it is involving the ano-genital region. Awareness among clinicians regarding the atypical presentations of molluscum contagiosum is imperative for early diagnosis and management of this infectious condition.