The Perils of 'Nephron-Wasting' Surgery
The broad application of cross-sectional imaging has led to the incidental discovery of small renal masses (SRM) as the most common presentation for localized kidney cancer.
As this stage migration unfolded, technological efforts at nephron preservation via open, laparoscopic, and robotic assisted techniques have evolved. Moreover, excision by partial nephrectomy is associated with excellent long term oncologic success.
Unfortunately, partial nephrectomy remains grossly underutilized. In a recently published Surveillance Epidemiology and End Results (SEER) review of national practice patterns, only 9.6% of patients diagnosed with SRM underwent partial nephrectomy (Miller et al. J Urol. 2006;175:853-857).
The long-term implications for the widespread use of “nephron-wasting” surgery for the SRM have only recently been described. In a study of 662 patients with two kidneys and a SRM, the three-year risk of CKD stage III was 65% after radical nephrectomy and only 20% after partial nephrectomy (Huang et al. Lancet Oncol. 2006;7:735-740).
Moreover, in a large population study of more than one million community-based patients, decreases in glomerular filtration rate were associated with significantly higher risks for cardiovascular events, hospitalizations and death (Go et al. N Engl J Med. 2004;351:1296-1305). In 2007, there were 33,875 additions to the kidney transplantation waiting list, with 55% of these individuals older than 50 years.
In the same year, 40% of the patients waited more than two years and 20% of those listed were removed due to death or medical unfitness, according to data reports on the United Network for Organ Sharing Web site.
Targeted surgical approaches to localized renal cancer must consider oncological as well as “nephrological” endpoints. The perils of “nephron-wasting” surgery cannot be overlooked. While “radical” minimally invasive approaches may shorten convalescence and improve cosmesis, the physiologic trade-off must be considered. In 2008, it is incumbent on referring and managing physicians to consider nephron-sparing surgery the gold standard for treatment of most localized renal malignancies.
