Patients with melanoma, the deadliest form of skin cancer, tend to have fewer nevi or moles, a new study found.
For this study, the researchers set out to examine whether or not the number of moles, including atypical ones, the age of the patient and the thickness of the tumor were related. Previous research has suggested that the overall number of moles that a person has can indicate risk of melanoma.
The team headed by Alan C. Geller at the Harvard T.H. Chan School of Public Health in Boston examined 566 patients within the first three months after they were diagnosed with melanoma. The majority of them, 376 or 66.4 percent, had zero to 20 moles in total. 415 patients (73.3 percent) did not have a single atypical mole.
After factoring in age, the researchers found that in patients younger than 60, those who had 50 total moles or more had a lowered risk of having thick melanoma. Patients in this age group who had at least five atypical moles, however, had a higher risk of having thick melanoma when compared to the patients with zero atypical moles.
Melanoma thickness can indicate the stage and the aggressiveness of the cancer.
"Several public health messages emerge from our study, including that melanomas are more commonly diagnosed in individuals with fewer nevi compared with those with a high mole count," the authors concluded. "Therefore, physicians and patients should not rely on the total nevus count as a sole reason to perform skin examinations or to determine a patient's at-risk status."
The study was published in JAMA Dermatology.
