Adding to evidence that men with early prostate cancer can safely put off surgery, a new study finds that patients who delayed surgery by over a year had similar outcomes as those who opted for immediate treatment.

Using a national cancer database, Swedish researchers found that among 2,566 men with cancer confined to the prostate gland, there was no evidence that men who delayed surgery were in worse shape once they did have the procedure.

Their tumors, on average, were no more likely to have extended beyond the prostate or have abnormalities that indicate a more aggressive cancer than men who had surgery soon after diagnosis.

Moreover, their long-term survival was nearly the same, according to the study findings published in the Journal of Urology.

After eight years, 0.9 percent of men in the delayed-surgery group had died, versus 0.7 percent of those who’d had prompt surgery.

“Our findings show that if a man is diagnosed with a localized low-risk prostate cancer, there is no rush to decide which treatment choice (is) best,” lead researcher Dr. Benny Holmstrom, of Gavle Hospital in Sweden, told Reuters Health in an email.

He said the results add to evidence that some men can safely opt for what is called “active surveillance” - where prostate cancer treatment is deferred and the disease is instead monitored with regular PSA blood tests, digital rectal exams and possibly prostate biopsies.

The issue is important because increasingly, experts are calling for expanded use of active surveillance in managing prostate cancer.

Since the introduction of widespread prostate cancer screening with PSA tests, a growing number of men have been diagnosed with early-stage tumors. The problem with this is that prostate cancer is often slow-growing and non-aggressive, so many men may be diagnosed with tumors that would never have caused them problems had they gone undetected.

This means that for some men, prostate cancer treatment can do more harm than good, as treatment carries a risk of side effects - including long-term urinary incontinence and erectile dysfunction.

In general, active surveillance (also known as “watchful waiting”) is an option for men with cancer confined to the prostate gland that has a low risk of rapid progression; “low risk” is determined by factors such as a relatively low PSA level and an absence of abnormalities in the prostate tumor that indicate a more aggressive cancer. According to the National Cancer Institute, about half of the more than 190,000 U.S. men diagnosed with prostate cancer in 2009 would fall into this low-risk group.

For the current study, Holmstrom’s team used the Swedish Cancer Register to identify 2,344 men who underwent prompt surgery for low-risk cancer between 1997 and 2002, and 222 men who underwent surgery after a period of active surveillance. All had a radical prostatectomy, where the entire prostate gland and some surrounding tissue are removed.

Men in the former group typically had surgery three months after their diagnosis, while those in the latter group had the procedure 19 months after diagnosis - most often prompted by a rise in their PSA levels or other signs of progression.

Overall, the researchers found no significant differences between the two groups as far as adverse tumor features at the time of surgery that could affect their long-term prognosis. And over a typical follow-up of eight years, there was no significant difference in their survival.

Holmstrom pointed out, however, that longer term studies are still needed to see whether choosing active surveillance does have an impact years down the road.

“Whether active surveillance represents an equally safe treatment approach as radical prostatectomy or radiation therapy in the aspects of prostate-cancer-specific mortality remains to be elucidated,” he said.

A limitation of this study, according to Holmstrom, is that during the study period, Sweden had no widely used criteria regarding active surveillance - so the findings reflect the typical clinical practice in Sweden. Since clinical practice varies by country, it is not clear how well the results might translate to other nations, like the U.S., according to the researchers.

A key difference between Europe and the U.S., Holmstrom said, is that active surveillance appears to be less commonly used in the U.S.

A study published last year in the Journal of the National Cancer Institute estimated that since 1986, as many as 1 million U.S. men have received treatment for prostate tumors that would have never threatened their lives.

SOURCE:  Journal of Urology, online August 18, 2010.