Active Surveillance for low risk prostate cancer
Active surveillance is a prostate cancer treatment strategy for where patients with small low risk cancer defer curative treatment until evidence of actual tumour growth is detected.
Studies have shown that the prostate cancer mortality associated with low risk prostate cancer is around 0.9% over 8 years in men on active surveillance. This has been shown to be only slightly higher than the 0.7% mortality who underwent immediate treatment for similarly low risk diseases.
(Holmstrom B, Holmberg E, Egevad L et al. Outcome of primary versus deferred radical prostatectomy in the National Prostate Cancer Register of
Sweden Follow-Up Study. J Urol 2010;184(4):1322-1327.)
The objective is to avoid unnecessary treatment of men with indolent or quiet cancer and thus avoid treatment-related side effects that may reduce quality of life for these men. Essentially, we are trying to avoid any impact on the urinary continence and sexual function of these men.
This strategy is only suitable for men who are motivated and are able to comply with a close follow up regime. They also need to be psychologically suited to watching their cancers.
The selection criteria of patients for active surveillance is broad and depends partly on patient factors such as the strength of the patient’s preference for active surveillance.
The evidence based review of the Prostate Cancer Foundation of Australia and Cancer Council Australia suggest that patients with the following criteria may be suitable:
- PSA≤20ng/mL
- Clinical stage T1–2 (disease may be palpable)
- Gleason score 6
Men with small amounts of Gleason score 7 cancer may also be eligible if they strongly prefer active surveillance.
Prostate Cancer Foundation of Australia and Cancer Council Australia PSA Testing Guidelines Expert Advisory Panel. Draft clinical practice guidelines for PSA testing and early management of test-detected prostate cancer. Prostate Cancer Foundation of Australia and Cancer Council Australia, Sydney (2016).
Although the exact protocols for active surveillance follow up are still the subject of study, we can say that monitoring needs to be very close
Currently, 3 monthly PSA and digital rectal examination every 6 months is recommended.
Repeat biopsy is usually recommended 12 months and then every 2-3 years. The need for these longer biopsies is under review with the role of prostate MRI in this regime being studied carefully at this time.
During active surveillance, definitive treatment should be offered if there is evidence of pathological progression such as an increase in the Gleason score of the cancer on follow up biopsies or of the proportion of higher grade disease increases. Changes such as a rapid rise in the PSA my be the trigger for repeat biopsy in addition to the routine or scheduled surveillance biopsies.
Patients themselves may request active treatment.
In a large Canadian study of men on active surveillance approximately 10% went on to active treatment due to progression of the grade of their cancers and 1.5% due to patient preference.
Long-Term Follow-Up of a Large Active Surveillance
Cohort of Patients With Prostate Cancer
Laurence Klotz, Danny Vesprini, Perakaa Sethukavalan, Vibhuti Jethava, Liying Zhang, Suneil Jain, Toshihiro Yamamoto, Alexandre Mamedov, and Andrew Loblaw J Clin Oncol 33:272-277 \
Active surveillance is a safe and feasible strategy for men with low risk prostate cancer that is becoming increasingly used.
All men with newly diagnosed low risk prostate cancer should carefully informed about the option of this treatment strategy.