Small kidney masses: Active surveillance could be an alternative to surgery
OXFORD, UK: Active surveillance of small kidney masses could be a safe and effective alternative to immediate surgery, with similar overall and cancer-specific survival rates, a new study has found. According to researchers at the Department of Urology at Churchill Hospital in Oxford, the technique, which is primarily used to treat elderly patients who have complex health issues or have declined surgery, could safely be extended to other selected patients.
“The incidence of kidney cancer has been increasing in Europe and the US since the 1980s and the use of more sophisticated imaging techniques means that smaller masses (of less than 4 cm) are being picked up at earlier stages,” said lead author Dr Nilay Patel.
“This has led to an increased rate of surgery for small kidney masses, but the benefits of this remain unclear. Conflicting reports on improvements in death rates for kidney cancer over the last few years suggest that increased detection may not necessarily be improving survival rates for patients with smaller tumours inside their kidney.”
In the study, 202 patients with 234 small renal masses of less than 4 cm—classified as T1a according to the TNM Classification of Malignant Tumours—were identified. Ninety were managed with partial nephrectomy (where only the diseased part of the kidney is removed), 41 with radical nephrectomy (where the entire kidney is removed) and 71 with active surveillance (where patients are monitored for disease progression).
The researchers found that over a median follow-up period of 34 months, the mean growth rate of the kidney masses in patients who were under active surveillance was 0.21 cm. However, 53 per cent of the small renal masses in these patients showed negative or zero growth.
No statistically significant differences were observed in overall and cancer-specific survival rates for patients who were under active surveillance or received partial or radical nephrectomy.
The overall survival rates were 83 per cent for active surveillance, 90 per cent for partial nephrectomy and 80 per cent for radical nephrectomy.
The cancer-specific survival rates were 99 per cent for active surveillance, 97 per cent for partial nephrectomy and 93 per cent for radical nephrectomy.
“Our research suggests that active surveillance of small kidney masses offers similar cancer outcomes to radical or partial surgery in the short and intermediate term,” Patel said. “The results of this study support the need for a multicentre, prospective randomised trial to compare how active surveillance and surgery compare when it comes to managing such patients.”
The study was published in the November issue of the BJUI urology journal.