Renal medullary carcinoma: molecular, pathological and clinical evidence for treatment with topoisomerase‐inhibiting therapy

STUDY TYPE: Aetiology (case series) Level of Evidence 4. OBJECTIVE: To present the molecular rationale and potential clinical benefit of topoisomerase II (TopoII)-inhibiting therapy for renal medullary carcinoma (RMC), a rare but extremely lethal form of kidney cancer that classically afflicts young men with sickle-cell trait. The current therapeutic approach with these aggressive tumours is radical nephrectomy followed by systemic chemotherapy, but the prognosis remains dismal. MATERIALS AND METHODS: The whole-genome expression was analysed in four RMC tumours. We also report a case of metastatic RMC in which a complete response was achieved for 9 months using a TopoII-inhibiting therapy. RESULTS: Expanded whole-genome expression analysis showed increases of TopoII in all cases. There was also overall deregulation of DNA remodelling and repair, and an ontological association between RMC and urothelial carcinoma. Using a TopoII-inhibiting agent, there was a complete response for 9 months in a patient with metastatic RMC. CONCLUSION: This report provides molecular evidence for the rational use of TopoII inhibitors in the treatment of RMC.