(ChemotherapyAdvisor) – Surveillance is an option for older patients with small renal masses for whom surgery is unacceptable, results of a retrospective analysis reported in advance of being presented during the 4th annual Genitourinary Cancers Symposium on February 16, 2013 in Orlando, FL.
“For older patients with small renal masses, surveillance does not appear to adversely affect kidney cancer–specific survival, while surgery may be associated with cardiovascular complications and an increased risk of death from any cause,” stated William C. Huang, MD, Assistant Professor of Urologic Oncology at New York University Medical Center, New York, NY, and colleagues.
In three of four cases, small renal tumors are detected incidentally, when a patient undergoes ultrasound, CT, or MRI imaging for an unrelated condition, such as gallstones, abdominal pain, or back pain. Nearly two thirds of newly diagnosed kidney tumors are small—less than 4 cm—and represent a heterogeneous group of tumors with varying malignant potential, Dr. Huang said.
He added that although surgery is the standard treatment for small renal masses, “emerging evidence suggests that surgical intervention in older or morbidly ill patients may be unnecessary and may also adversely affect non-oncologic outcomes.”
Using the Surveillance Epidemiology and End Results (SEER) cancer registry data linked with Medicare claims, the investigators performed a cohort study of patients 66 years of age or older who received surgery or surveillance for small renal masses diagnosed between 2000 and 2007. Surveillance was defined by the absence of a claim for surgery within the first 6 months following a diagnosis. The main outcome measures were to identify predictors of surveillance and assess its effect on overall survival, cancer-specific survival, and cardiovascular (CV) events when compared with surgery.
Of 8,317 patients identified, 7,148 with a diagnosis of kidney cancer either underwent surgery (78%) or surveillance (22%). Between 2000 and 2007, use of surveillance varied from 25% to 37%. During a median follow-up of 59 months, 24% of patients had at least one CV event and 21% died, including 3% who died of kidney cancer.
Compared with surgery, surveillance was associated with a significantly lower risk of a CV event (hazard ratio [HR] 0.51; CI: 0.44–0.60; P<0.00001) and with a significantly lower risk of death from any cause (6-month , 1.27; 7-36 month HR, 0.70; >36 month HR, 0.37). Kidney cancer–specific survival was not observed to differ by treatment approach (HR, 0.89; CI: 0.66-1.21).
Surgical treatment, particularly radical nephrectomy, was associated with cardiovascular complications and poorer survival over time, Dr. Huang said. Partial nephrectomies and laparoscopies are now more commonly performed to minimize the potential for kidney dysfunction, he added.
These 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 Dr. Huang. “However, since it is difficult to identify which tumors will become lethal, elderly patients who are completely healthy and have an extended life expectancy, may opt for surgery.”
The 2013 Genitourinary Cancers Symposium is co-sponsored by the American Society of Clinical Oncology (ASCO), the American Society for Radiation Oncology (ASTRO) and the Society of Urologic Oncology (SUO).