Background: The incidence of melanoma cutaneous and the mortalities rates are rising in most countries worldwide.
Objective: to describe the histopathological characteristics of cutaneous melanoma, according to the criteria established by the Brazilian Group of Melanoma, and to evaluate early diagnosis in a cancer treatment referral center.
Methods: we performed a cross-sectional descriptive study of cases of primary cutaneous melanoma identified after excisional biopsy and processed at the pathology laboratory of Complexo Hospitalar Santa Casa between Jan 1st 2000 and Jan 15th 2005. The following variables were analyzed: age, gender, topography, histopathologic subtype, Breslow thickness, growth phase, Clark level, mitotic index, peritumoral and intratumoral lymphocytic inflammatory infiltrate, angiolymphatic invasion, ulceration, regression, type of regression, microscopic satellitosis, and surgical margins.
Results: 328 cases, 57% female and 43% male, were analyzed. Mean age was 55.6 years. For women, the most common tumor location was in inferior(29.26%) and superior limbs(23.94%), while for men melanoma was mainly found in the back(35%), followed by anterior chest/abdomen(14.29%) (p<0.05). Prevalence of histologic subtypes was the following: superficial spreading melanoma(62.8%), lentigo maligna(14.9%), nodular(14.6%), acral(7.3%), and desmoplastic(0.3%) types. Regarding Breslow, 26.2% were in situ, 36.9% had <1 mm, and only 15.9% were ? 4mm in depth.
Conclusion: the distribution of histopathologic subtypes, as well as Breslow thickness, was in accordance with previous studies in outpatient populations. The profile of cases of cutaneous melanoma diagnosed in a tertiary hospital seems to be experiencing some changes over the last two decades, with a current trend for earlier diagnosis.