The present study was conducted as part of the Scandinavian Prostate Cancer Group collaboration (project SPCG-4). The conclusion drawn by the research team is that the PSA value for the period after the diagnosis is insufficient as a method of distinguishing with any certainty the men who will develop a fatal cancer from those with a slower tumour growth. In general, men with localised prostate cancer have a good chance of surviving the disease, even without treatment. Yet many still undergo major surgery or radiotherapy, which carries the risk of impaired sexual function and urine incontinence.
“We have to find better methods of separating the patients who will develop malignant prostate cancer from those with a more benign disease,” says PhD Katja Fall at Karolinska Institutet, one of the scientists behind the study. “This is important, not only to avoid unnecessary suffering, but also to make sure that hospital resources are directed towards the patients who need it most.”
Previous research has shown that there is a link between how quickly the tumour will grow and the speed with which blood levels of PSA increase in the first stages of the cancer. To examine how accurately PSA development can predict the patient’s prognosis, Dr Fall and her colleagues in the Scandinavian Prostate Cancer Group monitored 267 men from Sweden, Finland and Iceland diagnosed with prostate cancer between 1989 and 1999.
The PSA values measured in the first two years after diagnosis were used to describe the appearance of the early PSA curve for each patient. On follow-up at the end of 2003, 34 patients had died of prostate cancer and 18 had developed metastases but were still alive. Despite the fact that the PSA reading and the speed with which it increased during these first two years correlated with the development of aggressive prostate cancer, neither of these values was able to screen out with any certainty which patients would have needed intensive treatment from amongst those who would have managed just as well without.
“Prostate-Specific Antigen Levels as a Predictor of Lethal Prostate Cancer”
Katja Fall, Hans Garmo, Ove Andrén, Anna Bill Axelson, Jan Adolfsson, Hans-Olov Adami, Jan-Erik Johansson, Lars Holmberg
Journal of the National Cancer Institute, Vol. 99, nr 7. 4 April 2007