Department of Urology, Odense University Hospital, Odense, Denmark, Denmark
Background: Previous studies that investigated the relationship between diabetes mellitus (DM) and survival in patients undergoing nephrectomy for renal cell carcinoma (RCC) have reported inconsistent findings. This study aimed to investigate the impact of DM on overall survival (OS) in patients with RCC who had undergone nephrectomy.
Methods: Individuals with RCC who had a nephrectomy performed between 2000 and 2018 in Danish hospitals were included in this observational, retrospective register-based cohort study. Patients were identified from the Danish Cancer Registry and were divided into two groups according to their pre-surgical DM status. OS was investigated with Cox regression analysis.
Results: The study population consisted of 6,198 patients with RCC, of whom 5,424 (87.5%) did not have DM, while 774 (12.5%) had a presurgical diagnosis of DM. DM patients had lower OS rates with hazard ratios (HR) of 1.36 (p < 0.001). Other significant variables were found, including being male (HR 1.11 (p=0.015), and age groups compared to those under 60 years (HR60-69 years 1.44 (p < 0.001)., HR70-80 years 1.98 (p < 0.001), HR>80 years 2.86 (p < 0.001). The tumor, node, and metastasis (TNM) stages were also found to be statistically significant, indicating poorer OS.
Conclusions: This study indicates that DM has a significant impact on OS in patients with RCC who undergo nephrectomy, suggesting the need for differentiated treatment and monitoring. Future studies should investigate both the combined and separate impact of DM and nephrectomy on OS, and explore alternative surgical techniques, conservative treatments, and additional outcome measures to optimize care for DM patients.
