Second Primary Melanomas: Incidence and Outcome

Abstract

The objective of this study was to determine the incidence of multiple primary melanomas (MPM) and other cancers types among patients with melanoma. Factors associated with development of MPM were assessed in a post hoc analysis of the database from a multi-institutional prospective randomized trial of patients with melanoma aged 18 to 70 years with Breslow thickness 1 mm or greater. Disease-free survival (DFS) and overall survival (OS) were evaluated by Kaplan-Meier analysis. Forty-eight (1.9%) of 2506 patients with melanoma developed additional primary melanomas. Median follow-up was 66 months. Except in one patient, the subsequent melanomas were thinner (median, 0.32 mm vs 1.50 mm; P < 0.0001). Compared with patients without MPM, patients with MPM were more likely to be older (median age, 54.5 vs 51.0 years; P = 0.048), to have superficially spreading melanomas (SSM) ( P = 0.025), to have negative sentinel lymph nodes ( P = 0.021), or to lack lymphovascular invasion (LVI) ( P = 0.008) with the initial tumor. On multivariate analysis, age ( P = 0.028), LVI ( P = 0.010), and SSM subtype of the original melanoma ( P = 0.024) were associated with MPM. Patients with MPM and patients with single primary melanoma had similar DFS (5-year DFS 88.7 vs 81.3%, P = 0.380), but patients with MPM had better OS (5-year OS 95.3 vs 80.0%, P = 0.005). Nonmelanoma malignancies occurred in 152 patients (6.1%). Ongoing surveillance of patients with melanoma is important given that a significant number will develop additional melanoma and nonmelanoma tumors. With close follow-up, second primary melanomas are usually detected at an early stage.

Reduced disease‐specific survival following a diagnosis of multiple primary cutaneous malignant melanomas—a nationwide, population‐based study

“…who used a delayed‐entry model to analyze the impact of MPMs on CMM‐survival. Several previous studies have not detected significant differences in CMM‐prognosis and even improved CMM specific survival has been associated with the MPM‐group . The prognosis of MPMs is difficult to assess, being conditional on patients surviving the primary CMM.…”

“…The deaths cannot be attributed unequivocally to the first or subsequent tumor considered by Rowe et al . By indexing the first primary CMM in MPM‐patients and not including analysis of survival time before the second CMM in MPM‐patients, “guarantee time” may bias the results and contribute to overestimation of survival intervals . To overcome such bias, we grouped all patients as SPM‐patients until being diagnosed with a second CMM in the survival analyses.…”

“…The increasing number of patients diagnosed with invasive cutaneous malignant melanoma (CMM) that develop one or more additional CMMs, i.e., multiple primary invasive cutaneous malignant melanomas (MPMs), may be correlated to increasing incidence of CMM and improved survival over the last decades . The expected life time risk of an additional CMM varies between 1.3 and 8.6% .…”

“…The expected life time risk of an additional CMM varies between 1.3 and 8.6% . Several clinical and tumor‐related characteristics are associated with MPMs, e.g., older age, male gender, personal, or family history of CMM . Decreasing tumor thickness in subsequent CMMs has been reported .…”

“…Existing data on disease‐specific survival in patients with MPMs in relation to patients diagnosed with single primary invasive malignant melanomas (SPMs) are limited and show conflicting results . Previous studies have varied in study design (single‐center vs. population‐based), sample size, choice of index tumor, disease stages and endpoints analyzed . Further characterization of the outcome of MPMs may have implications for improved management and follow‐up.…”