519 Paranuclear cytokeratin aggregates help Merkel cell carcinoma evade extrinsic apoptosis

Abstract

Anti-PD1 therapy (pembrolizumab and nivolumab) is one of the treatment options for metastatic melanoma. According to literature there are predictors such as the neutrophillymphocyte ratio, the level of which at the time of initiation of the therapy indicates well the probability of biological therapy effectiveness. In our study stage IV melanoma patients treated with biological therapy were followed from the beginning of therapy to the week 12 at the Department of Dermatology of the University of Debrecen. We analysed the correlations between laboratory values at the time of the beginning of biological therapy or later on, the likelihood that the outcome of the disease will be determined by a laboratory parameter or by an early change in laboratory parameters, and the influencing factors of the progressive disease outcome. Totally 70 patients with stage IV melanoma who were treated with biological therapy were followed from the beginning of therapy to the twelfth week. Based on the radiological imaging methods on the twelfth week the outcome of disease was divided into three categories: progressive disease, stable disease and partial or complete response. The investigated biomarkers were S100B, LDH and neutrophil-lymphocyte ratio. Repeated measures variance analysis were performed, which was supplemented with a Newman-Keuls post hoc test, furthermore, correlation, ROC analysis and multivariate logistic regression were used. The results showed that none of the biomarkers can be used to determine the outcome of the therapy at the beginning. According to our results, based on the baseline laboratory parameters, we can not predict the outcome of the treatment, so we can not rely solely on laboratory values in deciding whether or not biological therapy should be started.