A large retrospective study of older patients diagnosed with small kidney tumours – less than 1.5 inches in diameter – showed that patients who undergo surgery to remove these tumours have the same risk of dying of kidney cancer over a five-year period as those who undergo surveillance.

Additionally, elderly patients treated with surgery for these small masses may be at greater risk for suffering a cardiovascular event and an earlier death from any cause.

The findings suggest that surveillance with imaging, such as MRI, ultrasound, and CT, is a safe option for the management of small renal masses in the elderly.

“Our analysis indicates that physicians can comfortably tell an elderly patient, especially a patient that is not healthy enough to tolerate general anesthesia and surgery, that the likelihood of dying of kidney cancer is low and that kidney surgery is unlikely to extend their lives,” said lead author William C. Huang, MD, Assistant Professor of Urologic Oncology at New York University Medical Center in New York.

“However, since it is difficult to identify which tumours will become lethal, elderly patients who are completely healthy and have an extended life expectancy, may opt for surgery.”

In 3 out of 4 cases, small renal tumours are detected incidentally – when a patient undergoes ultrasound, CT, or MRI imaging for an unrelated condition, such as gallstones, abdominal pain, or back pain.

Currently, the majority of patients diagnosed with a small renal mass receive surgery, which entails removal of either part of the kidney or the entire kidney.

However, emerging evidence has suggested that, for elderly patients or patients with co-morbid conditions and limited life expectancy, the risk of surgery may outweigh the benefit. 

In the study, researchers analyzed SEER registry data linked to Medicare claims for patients aged 66 years or older who were diagnosed with small renal masses. Out of 8,317 patients, 5,706 (70 percent) underwent surgery and 2,611 (31 percent) underwent surveillance. During a median follow up of 4.8 years, 2,078 (25 percent) patients died overall, 277 (3 percent) of kidney cancer. 

The rates of kidney cancer-related death were the same among patients who received surgery and those who underwent surveillance. Surveillance was also associated with a markedly lower risk of death from any cause as well as a lower risk of having a cardiovascular event, such as chronic heart failure, ischemic stroke, and vascular disease.

The study found that during the years 2000 through 2007, the percentage of patients managed with surveillance increased between 25 to 37 percent. It appears that doctors are beginning to realise that many small tumours do not pose a threat even if they are malignant. There is also increased awareness that removal of the kidney may lead to chronic kidney disease, which is associated with kidney failure, cardiovascular problems, and early death.

While 8 out of 10 small renal masses are malignant tumours, they generally don’t pose an immediate threat because they normally grow slowly and only a small number of them metastasize. Surveillance allows doctors to intervene if the tumour exhibits an aggressive growth rate or reaches a size that indicates a greater potential for spreading. “The risk of dying of kidney cancer in a person diagnosed with a small renal mass is small but real,” cautions Huang. “So, treatment considerations are different for healthy individuals, because they have a long life expectancy and a greater chance of having progression and spread of the disease.”

Source: ASCO