Prostate news article, February 2005
| ACTIVE SURVEILLANCE
FOR EARLY PROSTATE CANCER
Mr Majid Shabbir BSc(Hons) MBBS (Hons) MRCS(Eng) Urology Research Fellow, Royal Free Hospital, London |
Prostate Cancer is the most common cancer to affect men in the western world. With a high media profile and increased public awareness, it has come to the fore in the last few years. A constant source of debate in the management of prostate cancer has been the potential role of the PSA (Prostate Specific Antigen) blood test in screening the population to aid the early detection of the disease, and previous news articles on this website have explored this further. Part of the problem with picking up prostate cancer early is that we are still somewhat in the dark about its natural history - meaning we don't quite fully know how in develops, and in whom it is likely to be a serious problem, although certain factors have been shown to be indicative of a good outcome (for example the Gleason, or histological, grade of the cancer).
Studies have a shown that up to 80% of men with PSA screen detected prostate cancer may never develop any symptoms or complications from their disease (1). However radical 'curative' treatment with either radiotherapy or surgery, may lead to the development of complications associated with the treatment, which may affect an individual's quality of life. This finding has lead to the proposition of 'Active Surveillance' programs to closely monitor patients with evidence of less aggressive early prostate cancer to see if they develop any features of disease progression before offering radical treatment. This approach should allow a more individualized method of managing early detected prostate cancer.
In its essence, Active Surveillance differs from the traditional concept of 'Watchful Waiting', which has a more lax observation program and a view to start palliative hormonal therapy if there is evidence of disease progression. The concept of Active Surveillance was first formally described in 2001 by Choo et al. (2). In their study, they followed 206 men with clinical stage T1/T2 disease, Gleason score < 7 and a presenting PSA < 15ng/ml. After 29 months, 48 men had clinical progression and went on to have curative treatment (23%), 4 died of unrelated causes and the other 157 men remained on the Active Surveillance program with no evidence of disease progression (76%). A similar study at the Royal Marsden Hospital followed up 80 men with early prostate cancer between 1993 and 2001. Of the group, 10 required curative treatment (13%), 3 died from unrelated causes, while the remaining 67 men remained on the surveillance program (84%). No patients in this study developed metastases and no patient died from prostate cancer (3).
Dr. Chris Parker is currently still enrolling patients into the Active Surveillance Study at the Royal Marsden Hospital. Patients in this study have their PSA checked every 3 months for the first year, then every 4 months for the second year, and 6 monthly thereafter. Patients will need to have repeat prostate biopsies after every 2 years to ensure there has been no disease progression. Any man found to have a PSA doubling time of <3 years, or evidence of aggressive disease on repeat biopsy will immediately be offered curative radical treatment. In addition, any patient wishing to change their mind and have curative treatment may do so. At present, there are over 200 men in the program, but they are still recruiting more, which will help get a better outcome from their study.
Patients suitable for Active Surveillance include;
o Men aged 50-80 years
o Clinical Stage T1/T2 disease
o Biopsy proven prostate cancer
o Gleason Grade < 7
o PSA < 20
o No previous treatment for prostate cancer
Active Surveillance offers a different approach to the management of early prostate cancer, and may help reduce the number of patients requiring radical treatment, thereby reducing the potential complications of these procedures. Final publication of the results of this trial will have a significant impact on the way early prostate cancer is treated in the future and will be of substantial benefit to all men with asymptomatic PSA detected disease.
References:
(1) Yao SL et al. J Natl Cancer Inst (2002) 94(13):958
(2) Choo R et al. J Urol (2002) 167 (4):1664
(3) Parker C. Lancet Oncol (2004) 5(2):101