The ERSPC study indicates that over-diagnosis of prostate cancer, defined as the diagnosis of prostate cancer cases that might never surface clinically during life time, has been estimated to be as high as half of the cases diagnosed in the screening group.
Consistent estimates (a third of the screen-detected cancers) have also been obtained by identifying potentially indolent prostate cancer based on clinical and pathological characteristics. Overdiagnosis and unavoidable overtreatment are probably the most important adverse effects of prostate cancer screening.
Active Surveillance – potential alternative to surgery
In the case of prostate cancer, a new, more conservative form of monitoring called ‘Active Surveillance’ is emerging which might be an important method to help avoid early invasive treatment with some men with PSA levels under 10ng/ml.
Separate ERSPC findings also confirm that approximately 30% of detected cancers actually have non-aggressive features and are indolent or slow growing.
As Prof Chris Bangma, an ERSPC director and chairman of the urology department at Erasmus Medical Center, Rotterdam, explained: “Over an eight-year follow up, our studies indicate that 98 percent of patients offered active surveillance would not progress towards metastatic disease. This compares with other research showing at least 15 percent of men will still face a return of cancer, 10 years after standard surgical treatment or radiotherapy.”
The PRIAS Project (Prostate Cancer Research International Active Surveillance) was launched in March 2007 by Prof Bangma’s department. It takes the form of an online protocol for doctors to follow with their patients. It is a European initiative but open to all.
Prias is designed to help preserve quality of life during the management of a patient’s condition after cancer has been detected following screening.
Typical patient to be included in the PRIAS study
- Histologically proven cancer of the prostate
- Patient is fit for curative treatment
- Clinical Stage T1C or T2
- Adequate biopsy sampling
- One or two biopsy cores invaded with prostate cancer
- Gleason score of 3+3=6 or less
- PSA density of less than 0.2
- PSA-level at diagnosis of < 10ng/ml
- Participants must be willing to attend the follow up visits
Preserving quality of life in screened patients
”Under the Prias Project, carrying out ’active surveillance’ means that patients and their doctors work as a team – they monitor their PSA levels, symptoms and other markers and commit to doing this until – and only until – these markers change. Only if this happens and it indicates the cancer is developing will they need further treatment. We believe that we can save the quality of life of 30% more men in this way,” added Prof Bangma.