Cancer surgery choice may affect kidney disease onset

New York-Partial nephrectomy for small renal cortical tumors, while perhaps a more challenging procedure than radical nephrectomy, significantly delays the onset of kidney disease when compared with the far more common radical procedure, according to a retrospective study from Memorial Sloan-Kettering Cancer Center, New York.

This finding challenges current practices. It is a challenge that the study's authors readily acknowledge.

"Radical nephrectomy is a significant risk factor for the development of chronic kidney disease, and might no longer be regarded as the gold standard for small, renal cortical tumors," the authors wrote in the abstract of the study, published recently in The Lancet Oncology (2006; 7:735-40).

"Although both groups showed a decline in kidney function over time, function was preserved to a greater extent in those undergoing partial nephrectomies. The time to renal insufficiency and chronic kidney disease was longer," senior author Paul Russo, MD, associate attending surgeon in the department of urology at Sloan-Kettering, told Urology Times.

Dr. Russo, a urologic oncology surgeon noted for conducting kidney procedures through "miniflank" incisions, emphasized that the study focused solely on partial versus radical outcomes and in no way reflected upon the methods or technology used to conduct the operations.

'Do the right operation'

Recognizing that the study could prompt a shift in current approaches to kidney cancer treatment, Dr. Russo told Urology Times, "The point that needs to be made is to do the right operation for patients with small tumors."

GFR was selected as an outcome by the authors, who stated that it is regarded as the best overall measure of kidney function. GFRs were estimated with the abbreviated Modification of Diet in Renal Disease equation.

Postoperative differences between the two groups were significant and striking. The median time to development of GFR <60 mL/min per 1.73 m² (GFR <60) was 18 months for patients undergoing a radical procedure, but the median was not reached in the partial nephrectomy cohort. Sixty-nine percent of the radical nephrectomy patients developed postoperative GFR <60 compared with 17.4% of those undergoing a partial procedure. The hazard ratio of radical nephrectomy patients progressing to GFR <60 was 3.82 (p<.0001).