Expression rate of ALK tyrosine kinase and TAG-72 oncoprotein in primary skin melanoma

Abstract

Objective.Determine the frequency of occurrence of tyrosine kinase expression of the mutated ALK and TAG-72 gene among patients with primary melanoma of the skin, to identify their association with a number of histological parameters, and to assess the diagnostic value of the determination of ALK and TAG-72.Materials and methods.Paraffin blocks with surgical material from 40 patients with primary skin melanoma. For routine histological examination, the material was fixed with 10 % neutral formalin for 24 h, poured into paraffin, sections were prepared with a thickness of 4–5 μm, stained with hematoxylin and eosin. IHC study with monoclonal antibodies D57.3 to ALK was performed on an immunostender – Ventana, with antibodies B72.3 to TAG-72 – on Thermo Fischer. As a detection system used: Envision – for TAG-72 and Ventana – for ALK.Results.ALK mutation was detected in 7 (12 %), TAG-72 – 4 (10 %) cases. Evaluation of the correlation force between the presence of ALK and TAG-72 showed a direct average coupling strength (correlation coefficient was 0.31). A direct correlation of the mean force between the presence of TAG-72 oncoprotein, ALK mutation and ulceration in the patient was found – the correlation coefficient was 0.53 and 0.68, respectively. There was a statistically significant association between the presence of ALK and lymphoid infiltration, which in most cases (57 %) was pronounced (p <0.05).Conclusion.Comparing the positive sign of the expression of ALK – 17.5 % and TAG-72 – 10 %, and the positive of their simultaneous detection – 7.5 %, it can be concluded that further studies to determine their diagnostic value are promising. The presence of severe lymphoid infiltration in ALK-positive patients claims a diagnostic value in primary skin melanoma.