Variation in the management of cT1 renal cancer by surgical hospital volume: A nationwide study.

Objectives: To analyse variation in clinical management of cT1 renal cell carcinoma (RCC) in the Netherlands related to surgical hospital volume (HV). Materials and methods: Patients diagnosed with cT1 RCC during 2014-2020 were identified in the Netherlands Cancer Registry. Patient and tumour characteristics were retrieved. Hospitals performing kidney cancer surgery were categorised by annual HV as low (HV < 25), medium (HV = 25-49) and high (HV > 50). Trends over time in nephron-sparing strategies for cT1a and cT1b were evaluated. Patient, tumour and treatment characteristics of (partial) nephrectomies were compared by HV. Variation in applied treatment was studied by HV. Results: Between 2014 and 2020, 10 964 patients were diagnosed with cT1 RCC. Over time, a clear increase in nephron-sparing management was observed. The majority of cT1a underwent a partial nephrectomy (PN), although less PNs were applied over time (from 48% in 2014 to 41% in 2020). Active surveillance (AS) was increasingly applied (from 18% to 32%). For cT1a, 85% received nephron-sparing management in all HV categories, either with AS, PN or focal therapy (FT). For T1b, radical nephrectomy (RN) remained the most common treatment (from 57% to 50%). Patients in high-volume hospitals underwent more often PN (35%) for T1b compared with medium HV (28%) and low HV (19%). Conclusion: HV is related to variation in the management of cT1 RCC in the Netherlands. The EAU guidelines have recommended PN as preferred treatment for cT1 RCC. In most patients with cT1a, nephron-sparing management was applied in all HV categories, although differences in applied strategy were found and PN was more frequently used in high HV. For T1b, high HV was associated with less appliance of RN, whereas PN was increasingly used. Therefore, closer guideline adherence was found in high-volume hospitals.