Moles on the skin are a known risk factor for melanoma. A recent study of young teenagers examined risk factors associated with having mole-prone skin in late adolescence.
Melanoma, a type of skin cancer, causes mortality and continues to become more prevalent. Having pigmented moles in adulthood is a strong risk factor for melanoma. Many moles appear and change during childhood and adolescence, but few studies have focused on adolescents.
A study by Hoaming Xu and colleagues published in JAMA Dermatology examined risk factors in early adolescence (14 years of age) associated with having mole-prone skin in late adolescence (17 years of age).  A total of 569 students in 8th or 9th grade in Framingham, Massachusetts participated in the study (average age 14.4 years). In 11th grade, 417 of the students, now with an average age of 17 years, were reassessed. Race and gender data were collected from school system data; the group included 30 Hispanic, 11 Asian, and 4 African-American participants. Clinical images of the participants’ back and legs, as well as images of individual moles were collected. Additionally, participants completed surveys about sun sensitivity, sun protection practices, total sun exposure, sunburn frequency, and tanning habits. A sun sensitivity index (SSI) was developed using the above information. The SSI represents skin color, hair color, and tendency to burn versus tan.
A higher score is associated with fair skin, light hair, and higher tendency to sunburn. White participants were more likely to be mole-prone compared to non-white participants (OR, 4.14; 95% CI, 1.45- 11.84; P = 0.008). Those with the highest SSI were also more likely to be mole-prone compared to those with the lowest SSI (OR, 7.64; 95% CI, 1.76-33.12; P = 0.007). Additionally, both a history of sunburn and a higher number of moles counted in 8th grade was significantly associated with being mole-prone in 11th grade. Finally, analysis of the dermoscopic patterns of moles showed that more variable patterns or the presence of 3 or 4 pattern types were more likely to be associated with being mole-prone.
Overall, total mole count and variability of mole patterns were the key characteristics associated with being mole-prone in late adolescence. A better understanding of factors linked to being mole-prone at an early age may help improve skin cancer prevention approaches. Additional studies with a more diverse study population are needed.
Written By: Cindi A. Hoover, PhD
