"Active surveillance", involving annual biopsy, may be a better treatment option than tumor removal through surgery or
radiation therapy for older men with slow-growing prostate cancer that does not dramatically worsen over time, said US
The Johns Hopkins study of 769 men across the US found that close monitoring with biopsy did not raise risk of death and discouraged overtreatment in this group of older men with low-risk, very non-aggressive form of prostate cancer.
You can read how senior author Dr H. Ballentine Carter, a urologist at The Johns Hopkins Hospital and a professor at the Johns Hopkins University School of Medicine and its Brady Urological Institute, and colleagues, came to their conclusions in a paper published online this week in the Journal of Clinical Oncology.
Every year in the US about 217,000 men find out they have prostate cancer. Most of them are in their mid-60s or older and have a low risk of dying from the disease if they defer treatment. But more than 90% with low-risk cancer, including 80% of those aged 75 and over, opt for treatment rather than surveillance.
Carter told the press that their study showed the "most conclusive evidence" so far that active surveillance may work better for most older men diagnosed with a very low grade or small prostate cancer tumor.
"Our findings really underscore the need to address excessive treatment of this milder stage of the disease in older men, especially seniors," said Carter.
"These are men with a favorable risk disease profile to begin with," he added.
Although he acknowledges that some men just can't bear the thought of living with prostate cancer and just want it removed, Carter said active surveillance may be a better option for the vast majority of older men with this type of prostate cancer because it avoids the risks and complications of surgery and radiation, which can include incontinence, and other problems with bowel, urinary and sexual function.
However, he also cautioned that active surveillance is more suited to men who can be relied on to keep to their surveillance schedule and turn up for appointments. They make the best candidates for active surveillance, he said.
The prospective study started in 1995, when most of the recruited men were already past their 65th birthday, and followed them for a median period of 2.7 years (ranging up to 15 years, through to 2010). The surveillance comprised checkups every 6 months and biopsy every year.
The study is thought to be the largest and longest running study of men with slow growing non-aggressive prostate cancer.
Slow-growing, non-aggressive prostate cancer means the patient has a small chance of dying from the disease.
To take part in the study, the participants (90% white and 6% black) had to have very low risk cancers with a tumor at clinical stage T1c.
All of them met the key criteria that the cancer had to have a Gleason severity score of 6 or less (a score of 7 to 10 means the cancer is more aggressive and probably needs treatment).
80% of the participants involved in the latest analysis also met at least one of the other criteria for small-volume tumors. These included having a PSA density under 0.15 ng/mL, and biopsy findings with up to only two biopsy cores with cancer, and disease present in only up to 50% of any core.
The results showed that:
- The median period of treatment-free survival after diagnosis was 6.5 years (range was 0.0 to 15.0 years).
- The proportion of men who did not have treatment after 2 years was 81%, after 5 years it was 59% and after 10 years it was 41%.
- 255 men (33.2% of the total participants) had treatment at a median of 2.2 years (range was 0.6 to 10.2 years) after diagnosis.
- Of these 255 men, 188 (73.7%) had treatment because of reclassification of the tumor after biopsy.
- The proportions of men that had curative treatment or biopsy reclassification were significantly lower in those who met the full enrollment criteria than those who did not.
- The men who met the full enrollment criteria were 30% less likely to be reclassfied to a high-risk category during surveillance and thus require treatment compared to the men who did not meet them.
- None of the participants died from prostate cancer.
"For carefully selected men, active surveillance with curative intent appears to be a safe alternative to immediate intervention."
"Limiting surveillance to very-low-risk patients may reduce the frequency of adverse outcomes," they added.
The researchers are now planning to expand the surveillance to include other medical centers, such as the Cedars Sinai Medical Center in Los Angeles.
Current guidelines, endorsed by the National Comprehensive Cancer Network, already suggest active surveillance as a preferred option for many older men, said Carter.
To help men newly diagnosed with prostate cancer to find out more about active surveillance as an option, the study sponsors, the Prostate Cancer Foundation, and the team at Johns Hopkins are going to publish a web-based education program, and they also hope to develop improved screening tests to identify prostate cancer patients who would be best suited to active surveillance.
"Active Surveillance Program for Prostate Cancer: An Update of the Johns Hopkins Experience."
Jeffrey J. Tosoian, Bruce J. Trock, Patricia Landis, Zhaoyong Feng, Jonathan I. Epstein, Alan W. Partin, Patrick C. Walsh, and H. Ballentine Carter.
Journal of Clinical Oncology, published online on 4 April 2011.
Additional source: Johns Hopkins Medical Institutions (12 April 2011).
Written by: Catharine Paddock, PhD