According to a new study, models based on cancer registry data can help identify subsets of stage 1 melanoma patients with very low melanoma mortality. This finding, the authors note, may prevent the ‘over-diagnosis’ of melanoma that would never have caused symptoms or death. The study was published in Cancer.
Patients diagnosed in 2010 and 2011 with stage I melanoma lesions ≤1.0 mm thick and negative clinical lymph nodes were selected from the Surveillance, Epidemiology, and End Results database. These patients had a very low risk of dying from melanoma within seven years of diagnosis (2.5%), with a subset of 25% having a risk of just 1%, the international investigators noted. They developed and validated classification and regression tree and logistic regression models to confirm their findings.
The authors report that younger age at diagnosis and Clark level II were associated with a low risk of death in all models. Breslow thickness below 0.4 mm, absence of mitogenicity, absence of ulceration, and female sex were also associated with lower mortality. They did note that a subset of high-risk patients with >20% risk of death was also identified.
“Such cases warrant further study and consensus discussion to develop classification criteria, with the potential to be categorized using an alternative term such as “melanocytic neoplasms of low malignant potential,” the authors wrote.