Discussion
Published reports of nodular melanomas in patients of African descent
are rare. In the United States from 2004 to 2019, two case reports of NM
in AA have been published. 5,6 The SEER database
across 23 years records 87 cases of NM in AA, compared to 15,805 cases
in Caucasians. 1 Of the Asian races, melanoma
incidence is approximately twice as high in Japanese.2,4
Darker skin filters twice as much ultraviolet (UV) radiation as lighter
skin.2,7 In evaluating the relationship between
melanin and UV damage, Tadokoro et al, demonstrated that subjects with
darker skin repaired UV damage at a higher rate than lighter skin.8 Despite inherent photoprotection and higher rate of
repair, individuals with SOC exhibited significant UV damage,
highlighting that even with low UV exposure there is DNA damage to all
skin types.
V600E BRAF mutations have been identified in 66% of melanomas
and associated with increased thickness, tumor ulceration, and truncal
anatomic site. 9,10 NM is thought to arise from
chronic sun-exposure, with similar risk factors as SSM: fair skin,
freckling, and sunburns. 11 However, these risk
factors are not predictive of the risk of melanomas in AA. Our patient
received significant sun exposure during his time in service. His lesion
is consistent with intermittent sun-exposure and an anatomical site, the
abdomen, in which a BRAF mutation may occur.