Impact of comorbidity burden on renal cell carcinoma prognosis: A Danish nationwide cohort study.

Abstract

360 Background: The incidence of renal cell carcinoma is increasing worldwide and have a 5-year relative survival rates of around 75%. Comorbidity has been found to be associated with complications and mortality after renal cancer surgery. No studies have focused on comorbidity as a prognostic factor in a nationwide cohort of patients with renal cell carcinoma with long-term follow-up. Purpose: The primary aim was to evaluate the prognostic impact of comorbidity on survival in older (≥70 years) and younger (<70 years) patients diagnosed with renal cell carcinoma. Methods: We established a nationwide register-based cohort of 7,894 patients aged 18 or more diagnosed with renal cell carcinoma in Denmark between 2006 and 2017, and followed their vital status for up to 13 years. We computed 1- and 5-year overall survival and hazard ratios (HRs) of death according to comorbidity status using Charlson Comorbidity Index (CCI) among patients aged < 70 years and ≥ 70 years. Results: In all, 36% of the patients had registered comorbidity at the time of diagnosis. Survival decreased with increasing CCI score. It did though increase for all groups of CCI scores (0, 1-2 and 3+) over time. For patients without comorbidity diagnosed in 2006-2008 and 2015-2017, 5-year survival rate increased from 57% to 69%. For patients with a CCI score of 1-2 vs 3, the 5-year survival rate increased from 46% to 62% vs 39% to 44%. In age- and gender-stratified analyses, patients with a CCI score of 1-2 and 3+ had increased mortality compared to patients without registered comorbidity (HR 1.15, 95 % CI 1.06-1.24) and (HR 1.56, 95 % CI 1.40-1.73). Patterns were similar for older (≥70 years) and younger (<70 years) patients. Particularly, diagnoses of congestive heart failure, peripheral vascular and cerebrovascular disease, dementia, chronic pulmonary disease, preexisting renal and liver disease, diabetes and lymphoma led to increased mortality. Conclusions: Comorbidity leads to inferior survival outcomes in patients with renal cell carcinoma, irrespective of age, despite an overall increasing survival. These data may guide patient counseling and prompt initiatives for controlling comorbidity.