Carcinoma basocelular em áreas incomuns : aspectos epidemiológicos, clínicos e terapêuticos em hospital universitário de Vitória-Espírito Santo-Brasil

Abstract

Introduction: Basal cell carcinoma (BCC) is the commonest type of cancer among humans. About 85% are located on the face and trunk and 10-15% in usually photoprotected areas. Objective: To compare epidemiological, clinical and histopathological aspects of BCCs from non-photoexposed areas with those of photoexposed areas. Patients and methods: Observational, retrospective and casecontrol study of patients with clinical and histopathological diagnosis of BCC by the Dermatology Service of Vitória-ES, from 2008 to 2015. A total of 107 BCCs were assessed, from which 32 (29 , 9%) were located in non-photoexposed areas and 75 (71.1%) in photoexposed areas (nose). Results: The median age was 70 years; 62% of the patients were women as for the BCCs in the non-photoexposed regions; The commonest histological subtype in the two groups was the nodular one, followed by the superficial one in the non-photoexposed area, with 10 (31.3%) cases (OR = 2,051-5,267; p = 0,0001). Micronodular and baso-squamous subtypes were not observed in this group. Twelve (37.5%) cases in the non-photoexposed areas presented mild or absent elastosis (OR = 1,789-4,919; p = 0,0001). There was a predominance of a large number of mononuclears in the group of non-photoexposed areas: 12 (37.5%) cases, compared to eight (10.7%) cases in the photoexposed areas group (OR: 1,543-4,414; p = 0.002). Regarding the pattern of growth of BCCs, in the group of cases of the non-photoexposed areas, there was a predominance of the low risk pattern in 23 (71.9%) cases of nonphotoexposed areas versus 42 (56%) cases in the group of photoexposed areas (P = 0.137). Discussion: Despite the higher frequency of the nodular subtype in the two analyzed regions, the superficial subtype was more frequent in the non-photoexposed area, with a statistical difference, validating the literature. There was a higher frequency of moderate / severe elastosis in both regions, similar to the literature, but its absence was three times more likely to occur in the non-exposed area. The predominance of mononuclear cells in the non-photoexposed areas, possibly prevented the tumor from spreading. Regarding the pathological condition, the BCCs of the non-photoexposed areas were categorized as low risk in 65.5% of the cases. Conclusion: In the study, the BCCs in the non-photoexposed regions showed a better prognosis than the photoexposed areas, assessed through the histological factors.