The relationship of clinical and morphological parameters with the BRAF status of the tumor in patients with stage I skin melanoma

Aim : to study the relationship between clinical and morphological parameters of skin melanoma and the BRAF status of the tumor in patients with stage I of the disease. Materials and methods . The study was retrospective and included 200 patients with stage I skin melanoma (pT1-2aN0M0), of which BRAF status was assessed in 88 patients. All patients underwent clinical data analysis, an extended morphological study and a molecular genetic study to determine the BRAF V600E mutation in the primary tumor. Results . The median age of patients in the total sample was 61.5 years. Mutation in the BRAF V600E gene was detected in 25 patients (28.4%). Patient age, tumor location and Breslow thickness were recognized as independent predictors of BRAF status of stage I skin melanoma. With an increase in the patient's age by 1 year, the chance of having a BRAF V600E mutation decreased by 3.4% or 1.04 times (OR = 0.966; 95% CI = 0.935–0.999; p = 0.045). When melanoma was localized in the lumbar region, the chance of having a BRAF V600E mutation increased by 15.311 times (95% CI = 1.239–189.142; p = 0.033). With a tumor thickness according to Breslow of more than 0.7 mm, the chance of having a BRAF V600E mutation increased by 2.939 times (95% CI = 1.031-8.376; p = 0.044). With a threshold value of the logistic function of 50%, the sensitivity and specificity of the proposed model were 28.0% and 93.7%, respectively. When the threshold function value is reduced to 25.3%, the sensitivity of the model increases to 68% with a simultaneous drop in specificity to 61.9%. Conclusion . Younger age, greater tumor thickness according to Breslow, and tumor localization in the lumbar region in patients with stage I skin melanoma increase the chance of having a BRAF V600E mutation, while other morphological parameters of the tumor are not associated with BRAF status. However, moderate sensitivity does not allow for a sufficiently accurate determination of the presence of a mutation, thereby strengthening the belief in the need for molecular genetic testing.