Cardiovascular outcomes in kidney cancer patients

Abstract

Introduction: In the surgical management of small renal tumours, current guidelines recommend that partial nephrectomy should be the preferred option wherever possible. This is based on evidence suggesting improved quality of life outcomes, morbidity and mortality and equivalent oncological outcomes when compared with radical nephrectomy. Chronic kidney disease is a significant risk factor for cardiovascular disease and subsequent mortality. This study explored differences in cardiac-related events and co-morbidity, using linked registry data for patients undergoing radical or partial nephrectomy for T1 renal tumours. Methods: Data from the National Cancer Registration Service was searched to identify T1 renal cancer diagnoses between 1999 and 2012. This data was matched against hospital episode statistics to identify those patients who had undergone radical or partial nephrectomy between 1999 and 2013 using OPCS codes. Data was collected on cardiac-related admissions and deaths in nephrectomy patients. Equivalent data was also collected for the general population to allow age-standardized comparison. Charlson score was used as a proxy for pre-operative co-morbidity. Results: Radical/partial nephrectomy patients had a greater risk of cardiac-related admissions compared with the general population (relative risk (RR) 3.32, 95% confidence interval (CI) 3.24–3.40), but with no increase in cardiac-related deaths (RR 0.84, 95% CI 0.70–1.01). There was no difference in the admission risk, or death, comparing radical or partial nephrectomy for T1 renal tumours (RR 1.02, 95% CI 0.88–1.17) using ‘time to event’ analysis. There was no difference in the comorbidity index between radical nephrectomy and partial nephrectomy patients. Conclusion: The higher incidence of cardiac-related admissions seen for radical/partial nephrectomy patients may be explained by a higher proportion of patients with medical illnesses including cardiovascular risk factors (hypertension, diabetes) undergoing renal imaging. The absence of a difference between the radical nephrectomy and partial nephrectomy groups supports the phenomenon of surgically-induced chronic kidney disease, which may not have the same morbidity implications as medically-induced chronic kidney disease.