Prognostic factors for metastasis in cutaneous melanoma

Abstract

Background: Melanoma is a malignant neoplasia that shows high mortality when diagnosed in advanced stages. Early identification of high-risk patients for the development of melanoma metastases is the main strategy to reduce mortality.

Objective: To assess the influence of eight epidemiological and histopathologic features on the development of metastases in patients diagnosed with primary cutaneous melanoma.

Methods: Our historical cohort comprised patients with invasive primary cutaneous melanoma seen between 1995 and 2012 at a public university hospital and a private oncologic surgery institution in Southeastern Brazil. The following variables were analyzed: gender, age, family history of melanoma, site of the primary tumor, clinical and histologic subtype, Breslow thickness, histologic ulceration and the mitotic index. Kaplan-Meier univariate test and multivariate Cox proportional hazard analysis were used to assess factors associated with disease-free survival.

Results: Five hundred and fourteen patients were enrolled. The univariate analysis identified the following significant risk factors: gender, age, site of the tumor, clinical and histologic subtype, Breslow thickness, histologic ulceration and mitotic index. Multivariate analysis included 244 patients and detected four significant prognostic factors: male gender, nodular clinical and histologic subtype, Breslow thickness > 4mm, and histologic ulceration. The mitotic index was not included in this analysis.

Study limitations: Small number of patients in multivariate analysis.

Conclusions: The following prognostic factors to the development of melanoma metastasis were identified in the study: male gender, nodular histologic subtype, Breslow thickness > 4mm and ulceration.

Figure 1

Number of patients diagnosed with cutaneous melanoma with time, seen at the services of dermatology and surgical oncology (1995-2012)

Figure 2

Kaplan-Meier curves showing the interval for the occurrence of metastasis in patients with primary cutaneous melanoma according to gender (1995-2012)

Figure 5

Kaplan-Meier curves illustrating the time for the occurrence of metastasis in patients with primary cutaneous melanoma according to the presence of ulceration (1995-2012)

Figure 3

Kaplan-Meier curves illustrating the time for the occurrence of the metastasis in patients with primary cutaneous melanoma according to the clinicopathological type (1995-2012)

Figure 4

Kaplan-Meier curves illustrating the time for the occurrence of metastasis in patients with primary cutaneous melanoma according to Breslow thickness (1995-2012)