An overview of molecular testing in malignancies of the female genital tract

Abstract

Management of cancers in the twenty-first century has been defined by personalization. This has involved making more fine-grained distinctions between otherwise similar cancers on the basis of their genomic alterations, and providing more personalized therapies based on the presence or absence of particular biomarkers. This precision testing came relatively late to gynecological cancers, but we are now seeing an explosion in the number and variety of these tests. This review provides a practical overview of molecular and biomarker testing in solid cancers generally. It lays out the different types of alteration and the techniques used to test for them, comparing their strengths and weaknesses. It then explores how pathologists can ensure that the material which they submit for testing is optimized to provide the best results possible, including issues of ischemia, formalin fixation, decalcification and sample assessment. Finally, it explains how a genomic report should be interpreted with a particular focus on potential causes of misleading results. The second part of this review applies the general principles of molecular and biomarker testing to the specific cases of lower gynecological tract neoplasms: specifically PD-L1 immunohistochemical testing in cervical cancer and genomic testing of gynecological melanomas.