Children often present for evaluation of a melanocytic lesion that is new, evolving, or worrisome to parents and caregivers.
“In the pediatric health care system, malignant melanoma is considered an especially heinous crime. In San Diego, dedicated pediatric providers who identify this disease are members of an elite squad known as the mole patrol unit.” Dr. Sheila Fallon Friedlander opened her presentation on pediatric moles with this tongue-in-cheek statement, adapted from the popular TV show “Law and Order SVU,” at a pediatric dermatology meeting sponsored by Rady Children’s Hospital–San Diego and University of California, San Diego.
Dr. Sheila Fallon Friedlander
Only 104 cases were diagnosed in children aged less than 10 years, and the melanoma incidence in this age group was relatively unchanging from 1973 to 2009. Dr. Friedlander further emphasized, “Pediatric melanoma is extremely uncommon in patients less than 10 years of age, but more likely to be atypical.”
She continued by describing a group of surgical oncologists at MD Anderson Cancer Center in Houston, who conducted a retrospective review of children with cutaneous melanoma between 1988 and 2007 included in the SEER database, to determine the influence of age on disease presentation. Preadolescents younger than age 10 years were more ethnically diverse (nonwhite), more frequently presented with nontruncal primary melanocytic lesions, and increasingly were diagnosed with advanced disease, compared with their adolescent counterparts (J Pediatr Surg. 2013 Nov;48[11]:2207-13).
The National Cancer Institute
Congenital melanocytic nevi (CMN) may have increased risk for malignant potential, and can be challenging for pediatric providers to manage. Among all CMN, the increase in melanoma risk is estimated as less than 1%. The risk for malignant melanoma is further increased in individuals with large or giant CMN (greater than 20 cm diameter adult size), with an absolute risk of approximately 2%-5%. The number of satellite nevi also is considered in risk stratification. The presence of greater than 20 satellite nevi is associated with a greater than fivefold risk of neurocutaneous melanosis. There is no documented association between an increased quantity of satellite nevi and malignant melanoma.
“One particularly challenging pigmented lesion identified among pediatric patients is a Spitz nevus,” according to Dr. Friedlander. This lesion presents with greater cytologic atypia than other benign congenital and acquired nevi, and often clinically mimics malignant melanoma if identified in adults. There also exists a subset of atypical Spitz nevi, consisting of lesions with greater cytologic atypia than benign Spitz nevi. A retrospective review at Massachusetts General Hospital, Boston, of 157 cases of Spitz-type melanocytic lesions identified between 1987 and 2002 revealed increased melanoma risk, minimal mortality, and moderate risk of regional lymph node metastasis (Arch Dermatol. 2011;147[10]:1173-9).
“Classic pediatric Spitz nevi with typical clinical features and history may be managed conservatively with clinical monitoring alone, but those with concerning features such as bleeding, asymmetry, or ulceration should be excised with clear margins,” Dr. Friedlander emphasized. She discouraged sentinel lymph node biopsy, however, given the positive outcomes of 24 patients at Boston Children’s Hospital with atypical Spitz nevi treated with excision alone, published by Cerrato et al. (Pediatr Dermatol. 2011 Dec 30;29[4]:448-53).
“In light of the rising incidence of pediatric melanoma, we need to identify high-risk patients, educate about mole surveillance, and encourage sun protection,” Dr. Friedlander stressed. Children with phenotype of Fitzpatrick I (fair skin, blonde or red hair, and blue eye color) are at highest risk, as are those with a high density of freckles who burn easily and tan poorly. Further risk factors highlighted include excessive sun exposure, indoor tanning, use of phototoxic medications, immunosuppression, and genetics. The first and best line of defense against harmful ultraviolet radiation is covering up (clothing with a tight weave, wet suits, and hats).
The American Academy of Pediatrics encourages staying in the shade when possible, and limiting sun exposure during the peak sun intensity hours, between 10 a.m. and 4 p.m. When physical protection is not possible, the American Academy of Dermatology endorses the application of water resistant, broad spectrum SPF of greater than 30 at least every 2 hours.