Digital assessment of depth of invasion in melanoma using different immunohistochemical stains

Introduction. The most important histologic prognostic factors for melanoma remain depth of invasion and mitotic rate. In a digital era, precision (in terms of reproducibility and inter laboratories repeatability), as well as image evidence, are new qualitative parameters. The objective of the study was to evaluate in a retrospective analysis any significant difference among the Breslow digital assessments performed using two different immunohistochemical stains and the gold standard, hematoxylin eosin stain. Material and methods. We evaluated 130 primary cutaneous melanomas diagnosed in a two-year period (2016-2017) with known Breslow scale. Immunohistochemistry staining (SOX10 and Melan A) was perform followed by slide scanning. Aperio Imagescope and StataCorp software were used for data acquisition and statics. Results. No significantly statistic differences were recorded between groups in terms of Breslow values (p=0.98, Kruskal-Wallis test). Conclusions. All three stains perform similar in evaluating depth of invasion regardless of the method used to quantify it. The pathologist should consider using an accurate and precise method like a digital measurement technique for daily reports.