Invasive early prostate cancer treatments not always needed

Thursday September 15 2016

In some cases prostate cancer doesn’t spread

“Closely monitoring prostate cancer offers just as good a chance of survival as harsh and invasive treatments,” The Daily Telegraph reports.

Researchers found invasive treatments for early stage prostate cancer, such as surgery, didn’t help people live any longer when compared to active surveillance.

Active surveillance means a patient receives no immediate treatment, but instead, is given regular tests to check for signs of cancer progression. Some cases of prostate cancer can spread quickly. Many others never actually spread out of the prostate.

The headlines are actually based on two studies. The first looked at whether there were differences between survival outcomes if men received active surveillance, surgery or chemotherapy.

Survival rates were the same for all three groups; a 1% mortality rate during a 10 year follow up period. That said, men who had active monitoring of their cancer were more likely to see the cancer spread to other parts of the body, and half of them went on to have surgery or radiotherapy during the 10-year follow up.

However, a second study of the same patients showed they were much less likely to have side effects of treatment, especially sexual problems and urinary incontinence, than men who had surgery or radiotherapy at the study’s start.

These results don’t apply to men who are diagnosed with advanced prostate cancer.

It is important to discuss all possible care options with the doctor or team in charge of your care. Sometimes choosing not to treat a condition immediately is the best option.

 

Where did the story come from?

The research was carried out by researchers from 13 UK universities and hospitals, led by the Universities of Oxford and Bristol, and was funded by the National Institute for Health Research. The studies were published in the peer-reviewed New England Journal of Medicine.

Most of the media reports focused on survival rates of the different treatments, although The Guardian and BBC News also included information about the chances of side effects with surgery or radiotherapy.

The general tone of the reporting was accurate in pointing out that active surveillance could well be the best initial option for men with early stage prostate cancer.

 

What kind of research was this?

These two studies were randomised controlled trials, which is the best type of study for comparing the results of different treatments.

However, in a study of such different treatments, it would not be possible to “blind” people to whether they had surgery, radiotherapy or active monitoring of the disease, so it’s not a double blind study.

Researchers wanted to know how the type of treatment affected people’s chances of dying from prostate cancer, the chances of cancer spreading, and the effects on sexual function, urinary and bowel function and their overall quality of life.

 

What did the research involve?

Researchers invited 82,429 men to have screening with a prostate-specific antigen (PSA) test. The test can check to see if the prostate is enlarged, but as the prostate usually grows larger as men grow older, a diagnosis of prostate cancer usually needs to be confirmed with a biopsy.

Of the 2,664 men who were subsequently diagnosed with localised prostate cancer, 1,643 agreed to take part in the study. These men were randomly divided into three groups:

• active surveillance (also known as active monitoring) of their cancer
• surgery to remove the prostate gland (prostatectomy)
• radiotherapy and hormone therapy intended to destroy the cancer and prevent it growing

They were followed up for an average of 10 years, during which time they were sent questionnaires about their symptoms and quality of life. The researchers then compared what had happened to men in each treatment group, reporting separately on the mortality results and the quality of life results.

Men who had active monitoring had their PSA level checked every three months in the first year, then every six to 12 months after that. If the PSA level increased by more than half, they and their doctors considered whether to continue with active surveillance or have surgery or radiotherapy.

The two studies of treatment are part of a larger study looking at the effects of PSA screening. The 2,664 men diagnosed with localised prostate cancer had all had PSA tests, without showing any signs of cancer, as part of this bigger study.

At present, men can ask their GP for a PSA test, but it’s not offered routinely, because there’s no good evidence that PSA screening reduces the number of men who die from prostate cancer.

 

What were the basic results?

The main finding was that about 1 in 100 men died of prostate cancer during the 10 years of follow-up, regardless of the type of treatment they’d been assigned to. Deaths from other causes were the same in all three groups, at 9%.

However, 53% of the men who’d started with active monitoring had switched to surgery or radiotherapy by the end of the study, and 20.5% had showed signs of cancer progression. Only about 8% of men who had surgery or radiotherapy showed signs of cancer progression, although it’s difficult to compare this between the groups.

Men who had a prostatectomy were much more likely to have had problems with sexual function (including inability to get an erection firm enough for sex) or to have had urinary incontinence.

Only 12% of men who’d had prostatectomy were able to have penetrative sex six months after the start of the study, compared to 22% who’d had radiotherapy and 52% who’d had active monitoring. Almost half (46%) of men who’d had surgery needed to use absorbent pads for urinary incontinence at six months, compared to 5% and 4% of men who’d had radiotherapy or active surveillance.

Although these figures improved over time, men in the surgery group continued to have worse outcomes in these areas than the other groups throughout the study. Bowel function deteriorated somewhat among men who’d had radiotherapy, but recovered later.

Men’s overall quality of life was roughly the same across the three treatment groups, and no group had more anxiety or depression than another.

 

How did the researchers interpret the results?

The researchers say their findings give men useful information to consider their options: “Men with newly diagnosed, localised prostate cancer need to consider the critical trade-off between the short-term and long-term effects of radical treatments on urinary, bowel and sexual function and the higher risks of disease progression with active monitoring.”

Importantly, they warn that “longer term survival data will be crucial” to find out whether the higher rates of cancer progression for men having active monitoring translate into shorter length of life beyond the first 10 years after diagnosis.

 

Conclusion

Decisions about treatment for prostate cancer are fraught with difficulty, especially in the early stages. Because many prostate cancers grow very slowly, some men don’t need treatment and will never be bothered by their cancer.

However, some cancers grow and spread around the body, and can be fatal if not treated. Until now, there’s been insufficient good information to help men decide whether to choose surgery, radiotherapy or active monitoring.

These studies give us the best evidence yet to compare the results of the three most commonly-used treatments. The results don’t tell us that one treatment is better for everyone, but mean that men can compare and discuss their options with doctors and their families, before making a choice that reflects their own priorities and values.

Some men will want to have surgery or radiotherapy straight away to avoid the risk of the cancer progressing, and will accept the chance of side effects. Others will prefer to wait and have their disease monitored, in the hope of avoiding side effects.

Men may find it reassuring that few men died of prostate cancer during the study, and that choice of treatment didn’t affect their survival chances 10 years after diagnosis.

There are some points to be aware of, however:

• 10 years may be too short a time to properly assess the effects of treatment on length of life.
• Men who had treatment later, after initial active monitoring, may do worse over the long term.
• This research is ongoing so we will have more information in future.
• Treatments for prostate cancer are changing all the time, and these studies represent treatments carried out 10 years ago. Newer treatments, such as implanting radioactive seeds into the prostate, were not included in the study.
• A proportion of each group did not have the treatment allocated to them.
• Few men in the studies were from African Caribbean backgrounds, which may mean the results don’t apply to that group.

However, these studies were large, randomised controlled trials, carefully designed and carried out, with a high level of successful follow-up. They represent an important advance in doctors’ understanding of the comparative effects of common treatment options for this common cancer.