Management and outcomes of patients with renal medullary carcinoma: a multicentre collaborative study.

Objective: To describe the management strategies and outcomes of patients with renal medullary carcinoma (RMC) and characterise predictors of overall survival (OS).

Patients And Methods: RMC is a rare and aggressive malignancy that afflicts young patients with sickle cell trait; there are limited data on management to date. This is a study of patients with RMC who were treated in 2000-2015 at eight academic institutions in North America and France. The Kaplan-Meier method was used to estimate OS, measured from initial RMC diagnosis to date of death. Cox regression analysis was used to determine predictors of OS.

Results: In all, 52 patients (37 males) were identified. The median (range) age at diagnosis was 28 (9-48) years and 49 patients (94%) had stage III/IV. The median OS for all patients was 13.0 months and 38 patients (75%) had nephrectomy. Patients who underwent nephrectomy had superior OS compared to patients who were treated with systemic therapy only (median OS 16.4 vs 7.0 months, P < 0.001). In all, 45 patients received chemotherapy and 13 (29%) had an objective response; 28 patients received targeted therapies, with 8-week median therapy duration and no objective responses. Only seven patients (13%) survived for >24 months.

Conclusions: RMC carries a poor prognosis. Chemotherapy provides palliation and remains the mainstay of therapy, but <20% of patients survive for >24 months, underscoring the need to develop more effective therapy for this rare tumour. In this study, nephrectomy was associated with improved OS.