Trends in kidney cancer: Exploring the impact of sex and age on stage of disease, and prognosis during the past three decades in Denmark—A DaRenCa study.

Abstract

485 Background: Over the past 30 years, renal cell carcinoma (RCC) management has undergone significant advancements, driven by increased diagnosis through imaging scans and the development of more effective systemic therapies for metastatic disease. Understanding the impact of early detection and evolving treatment strategies on patient outcomes is crucial for guiding future advancements in RCC care. This nationwide registry-based cohort study investigates how the number of RCC cases, stage at diagnosis, and prognosis have changed during the past 30 years in Denmark, and how these are associated with sex and age. Methods: A population-based cohort was established, including all Danish patients aged 18 and older diagnosed with RCC from 1992 to 2021, excluding individuals with a prior cancer history. Patients were identified and followed from the date of diagnosis until death or end of follow-up using nationwide register data. Comorbidities prior to RCC diagnosis were assessed using nationwide hospital admittance records. Results: A total of 17,423 RCC patients were diagnosed during the past 30 years in Denmark. The male-to-female ratio changed significantly from 0.59:0.41 in 1992-1996 to 0.72:0.28 in 2017-2021 (P < 0.001). The age distribution of patients at diagnosis remained relatively constant (ranging from 65-67 years). The number of RCC cases increased from 2,244 in 1992-1996 to 3,947 in 2017-2021. We observed stage migration over time, with Stage I cases increasing from 30% in 2002-2006 to 55% in 2017-2021, and Stage IV cases decreasing from 45% in 2002-2006 to 20% in 2017-2021, while the absolute number of metastatic cases remained relatively unchanged. The median survival of patients with metastatic disease steadily increased by 314% from 4.1 months in 1992-1996 to 12.9 months in 2017-2021. Additionally, married patients showed better survival than divorced and unmarried patients. Conclusions: During the past 30 years, the number of RCC cases in Denmark has increased, primarily driven by early-stage tumors, while the number of metastatic cases has remained stable. Additionally, the proportion of female patients has decreased across all stages of RCC during the observation period. Overall survival has significantly improved over time, highlighting the impact of early detection and treatment advancements. Despite only studying Danish patients, this study serves as a reference for how patient dynamics have evolved with the advancements in the diagnosis and treatment of RCC.