Hospital variation in the treatment of cT1a renal cancer

Objectives: To evaluate treatment patterns and inter-hospital variation of cT1a renal cell carcinoma (RCC) in seven Dutch teaching hospitals. Patients and methods: In this historical multicenter cohort study, adults diagnosed with cT1a renal cancer (2019–2022) were identified through the Netherlands Cancer Registry. Clinical data were extracted from electronic records. Primary outcome was initial treatment. Descriptive statistics and subgroup analyses assessed variation. Logistic regression analyses identified factors associated with active treatment. Results: We included 501 patients with 544 cT1a renal cancer tumours. Mean age was 66 years, 40% were overweight (BMI 25–29.9), and 40% had severe comorbidity (CCI ≥ 5). Active treatment was initiated for 65% of tumours, ranging from 44% to 85% between hospitals (p < 0.001). The types of treatment modalities used differed significantly between hospitals. This variation persisted after stratifying for comorbidity and tumour complexity. Independent factors associated with active treatment were Charlson comorbidity index (CCI) (OR = 0.77 95%CI [0.72–0.83], p < 0.001) RENAL Nephrometry score (OR = 1.16 95%CI [1.04–1.28], p = 0.006), and hospital of diagnosis (p < 0.001). After adjustment for case mix, hospital of diagnosis remained a significant predictive factor (p < 0.001). Study limitations include potential selection bias and limited generalizability. Conclusions: Substantial inter-hospital variation exists in cT1a RCC management, which is not fully explained by patient- or tumour characteristics. To reduce unwarranted variation and improve care, transparent care pathways, routine outcome measurement, shared decision-making and inter-hospital benchmarking are needed.