Growth Kinetics in Von Hippel-Lindau-Associated Renal Cell Carcinoma

Abstract

Objective: To evaluate the growth kinetics of renal cell carcinoma (RCC) in von Hippel-Lindau (VHL) disease in a large trial by CT/MRI scan. VHL disease is a multisystemic disorder predisposing to renal cysts and cancer. There is a general assumption that VHL-associated RCC presents slower growth rates than sporadic RCC. Patients and Methods: We describe growth kinetics of 96 renal tumours in 64 VHL patients with analysed germline mutation (54/64 treated, 10/64 active surveillance) over a mean follow-up of 54.9 months. We calculated tumour volume, growth rate, multiplication of tumour volume per year and overall, as well as tumour volume doubling time. Results: The mean growth rate of 96 tumours was 4.4 mm/year (SD 3.2, median 4.1 mm/year), mean volume doubling time was 25.7 months (SD 20.2, median 22.2 months). We saw a median 1.4-fold increase in tumour volume per year. At treatment time point, VHL kidneys comprised 39% tumour and 15.7% cyst volume fraction. We saw no correlation between tumour size and growth parameters. Conclusion: VHL-associated RCC show large variances in tumour growth behaviour. Compared to the literature, in our study the growth rates (mm/year) of RCC in VHL disease did not differ from those of sporadic RCC. Fast tumour growth increases the risk for metastases.