Low-risk prostate cancer: monitor, irradiate, operate?

Photo of a man lost in thought (PantherMedia / Jean-Paul CHASSENET)

Men who have prostate cancer that isn’t aggressive and hasn’t spread to other parts of the body have three treatment options: radiotherapy, surgery, and an approach known as active surveillance. A large study compared the three approaches with each other.

In order to be able to find out more about the tumor, tissue samples are taken and looked at under a microscope. The tumor is then classified based on certain fixed criteria. Tumors that are discovered following a PSA screening test are often low-risk prostate cancer. Because this type of prostate cancer often grows very slowly, there is an alternative to surgery or radiotherapy: “active surveillance.” In this approach, the cancer is monitored regularly. Treatment with radiotherapy or surgery is only considered if it grows, becomes more aggressive or causes problems.

This has the advantage of avoiding surgery or radiotherapy, as well as the possible side effects, in men whose cancer doesn’t progress (grow). The disadvantage is that if the cancer progresses it may be discovered too late.  Active surveillance also involves a lot of check-up appointments, and knowing that you have cancer in your body can be distressing.

A study known as the ProtecT trial is the most conclusive study on treatments for low-risk prostate cancer so far. It looked into how active surveillance compared with surgery and radiotherapy. “ProtecT” comes from the longer name “prostate testing for cancer and treatment.”

The ProtecT trial

The ProtecT trial included men between the ages of 50 and 69 whose prostate cancer was discovered because they had high PSA levels. They were all asked whether they could be randomly assigned to one of the three treatment groups:

  • Active surveillance: The men in this group didn’t have treatment, or at least not straight away. They had a PSA test every three months in the first year of the study, and every six to twelve months after that.  If the PSA levels were too high or if the men developed symptoms such as problems urinating, they had further tests and, for instance, were advised to have a biopsy (tissue samples taken). If there were signs that the cancer had grown, the treatment approach was reconsidered.
  • Radiotherapy: The men in this group had radiotherapy from outside of their body (external radiotherapy) to destroy the cancer cells.
  • Surgery to remove the prostate: The men in this group had surgery to remove their whole prostate, as well as the seminal vesicles.

A total of 1,643 men with low-risk prostate cancer agreed to be assigned to one of the three treatment groups. There were about 550 men in each group.

The treatment outcomes were recorded over an average of ten years, and then compared with each other at the end of the trial. The following table shows what men can expect from the three treatment options regarding aspects that are important to them: survival, the need for treatments, and the likelihood of side effects.

Comparison of treatment options for low-risk prostate cancer Comparison of treatments

When looking at the results of the study, it’s important to remember that they have only been collected over a time period of ten years so far. It will only be possible to draw any reliable conclusions about the advantages and disadvantages of the treatments after 15 or 20 years. What’s more, the check-up examinations in the study are a little different to those that are usually done in everyday clinical practice. In Germany, men who follow the active surveillance approach are also offered regular biopsies to check for changes in the tumor tissue, even if their PSA levels are normal and they don’t have any symptoms. This is meant to increase the likelihood of finding out soon enough if the cancer progresses, but it can also be more distressing.

Carefully considering the pros and cons

Men who have low-risk prostate cancer, for whom the active surveillance approach is an option, can take their time to weigh the pros and cons of the different treatments. Active surveillance may make it possible to completely avoid – or at least delay – surgery or radiotherapy and the possible side effects. On the other hand, this approach is associated with a greater risk of the cancer growing and a somewhat higher risk of it spreading to other parts of the body (metastasis). So it’s important to have regular check-ups.

Other factors, such as the man’s age and how healthy he is overall, will play an important role in the treatment decision too. A young and otherwise healthy man who is still expected to live for a long time will probably weigh the pros and cons of the treatment options differently than an older man who may have other medical problems and a shorter life expectancy.

It is best to discuss the pros and cons of the possible treatments with your doctors.