What the LDH.
The Study: Because what doesn’t elevate LDH, really. If you can’t tell yet, it’s officially GU Malignancy Biomarker Week, and today we focus on testicular cancer. Most men with a suspicious testicular mass have alpha fetoprotein (AFP), β-HCG, and LDH drawn before and after orchiectomy. These tests are foundational in determining both the stage and optimal treatment approach for GCT. But just how useful are these markers? By definition, they tell you almost nothing about pure seminoma, and only half of any GCT express even one of these markers. Enter this prospective, multicenter study that describes the utility of the novel biomarker M371 in the diagnosis, treatment, and surveillance of GCT. M371, short for miR-371a-3p but not short enough to fit the strict three-character requirement for GCT biomarkers, is a microRNA cluster that is strongly associated with GCT. Among a broad cohort of patients with testicular masses at initial presentation, M371 had a 90% sensitivity and 84% specificity for GCT. It was widely expressed among almost all the GCT histologies, with the exception of low expression in teratoma, and outperformed the three classic serum biomarkers. M371 also strongly correlated with tumor bulk, stage, and response to treatment. Finally, the test had a >80% sensitivity for recurrent disease.
Bottom Line: M371 is a much-needed highly-sensitive and specific biomarker for testicular GCT. | Dieckmann, J Clin Oncol 2019