FIVE RISK FACTORS PREDICT PROGRESSION OF RENAL CELL CARCINOMA AFTER SURGERY

NEW YORK (Reuters Health) Apr 22 - Five factors can predict progression of localized renal cell carcinoma after surgery, according to new research.

These factors are stage pT2 tumors (7 cm or larger), male gender, symptomatic presentation, sarcomatoid de-differentiation, and macroscopic necrosis on pathology.

The findings are drawn from a cohort study of 925 patients followed for a median of 48.2 months. In an April 15th online paper in BJU International, the researchers report that of 618 patients who had one or two risk factors, 20 (3.2%) progressed to metastatic disease at a median of 37.1 months. Of 130 patients with three or more risk factors, 33 (25.4%) progressed at a median of 25.2 months. Meanwhile, there was no progression in any of the 177 patients with none of the risk factors.

"This risk stratification can be used to follow up patients," senior author Dr. Christopher Wood of the University of Texas M. D. Anderson Cancer Center in Houston told Reuters Health by e-mail.

He continued, "In theory, if a patient has no risk factors, they would not need any followup after definitive surgery. Furthermore, those with three or more risk factors need to be followed very closely for evidence of recurrence. (These are) very timely data in light of the issues surrounding radiation exposure from imaging studies and risk of secondary malignancy."

Dr. Wood and his colleagues identified their subjects through a review of their hospital's records from 1994-2007. The patients had undergone partial or radical nephrectomy for renal cell carcinoma. The researchers excluded patients with multi-focal tumors, bilateral disease, inadequate follow-up, or local disease recurrence after surgery.

There was progression to metastatic disease in 53 patients, representing 5.7% of the group. Progression occurred in 20 (2.6%) of 774 patients with pT1 cancer and 33 (21.9%) of 151 with pT2.

The researchers identified 11 risk factors and whittled them down to five through multivariable stepwise logistic regression analysis and construction of a receiver operating characteristic curve.

"Male gender and macroscopic necrosis were two that hadn't been reported before and therefore were a bit surprising," Dr. Wood said. "Microscopic histologic necrosis has been reported by Mayo, but not macroscopic in this population."

BJU Int 2010.