A. P. Woods1, 2, M. V. Papageorge1, S. W. De Geus1, S. Ng1, M. H. Katz3, D. McAneny1, J. F. Tseng1, T. E. Sachs1, K. M. Kenzik1, 4, F. T. Drake1 1Boston University, School Of Medicine, Department Of Surgery, Boston, MA, USA 2Johns Hopkins University School Of Medicine, Department Of Surgery, Division Of Surgical Oncology, Baltimore, MD, USA 3Boston University, School Of Medicine, Department Of Urology, Boston, MA, USA 4University Of Alabama at Birmingham, Division Of Hematology And Oncology, Birmingham, Alabama, USA
Introduction: Adrenalectomy is often performed in an effort to improve survival for patients who have developed adrenal metastasis from renal, pulmonary, or other malignancies. However, no multicenter comparative studies have examined the effect of adrenalectomy on survival. We investigated the impact of adrenalectomy upon survival after the development of adrenal metastasis from renal cell carcinoma (RCC).
Methods: Patients diagnosed with stage I-III RCC from 2008-2015 who underwent nephrectomy and developed metachronous adrenal metastases were identified from the SEER-Medicare linked database. Propensity scores were created for the probability of undergoing adrenalectomy using the following variables: age, stage at diagnosis, Elixhauser comorbidity index, and time interval between nephrectomy and development of adrenal metastasis. Patients were matched 1:1 using greedy nearest neighbor matching. The primary outcome was overall survival (OS) after development of adrenal metastasis, evaluated using the Kaplan-Meier method and log-rank test.
Results: We identified 243 patients with RCC and metachronous adrenal metastasis, of whom 65 (26.7%) underwent adrenalectomy and 178 (73.3%) did not undergo adrenalectomy. Median age at development of adrenal metastases between the groups was similar (median 73 years in the adrenalectomy group vs. 76 years in the non-adrenalectomy group, p=0.842). Stage of RCC at diagnosis was comparable between groups (p=0.193). Categorized Elixhauser comorbidity index was lower in the adrenalectomy group compared to the non-adrenalectomy group (p=0.002). The median time from nephrectomy to development of adrenal metastasis was similar across groups (24 months in the adrenalectomy group vs. 28 months in the non-adrenalectomy group, p=0.145). Prior to matching, patients who underwent adrenalectomy demonstrated longer OS after the development of adrenal metastasis (median 48 months vs. 10 months, p<0.001) and from initial RCC diagnosis (median 82 months vs. 57 months, p<0.001). After matching, patients who underwent adrenalectomy continued to demonstrate longer OS after the development of adrenal metastasis (median 47 months vs. 16 months, p<0.001) and from initial RCC diagnosis (median 73 months vs. 57 months, p=0.007).
Conclusion: Adrenalectomy was associated with substantially longer survival after development of RCC adrenal metastasis in the Medicare population. Larger scale investigations are needed to allow for more detailed adjustments for receipt of non-surgical treatments and presence of additional sites of metastasis. Ensuring access to adrenalectomy may enhance survival for appropriately selected patients with metastatic RCC.
