The PRIAS (Prostate Cancer Research International: Active Surveillance) study has been ongoing observational study since December 2006 focusing on early prostate cancer (cT1c-T2N0M0). It has now accrued over 7500 patients in 22 countries!
- Inclusion criteria (is relatively strict compared to other AS studies):
- PSA <= 10 ng/mL
- PSAD < 0.2
- cT-stage T1c or T2
- Gleason score 3+3=6 only
- Only 1-2 biopsy cores involving cancer
- Patients are following, and have repeat biopsies at 1, 4, 7 and 10 years (and then every 5 years after)
He highlighted other large AS results as well, including:
1. Johns Hopkins (Tosoian et al JCO 2015) – 10 and 15-year CSS was 99%. 10 and 15-year OS was 93 and 69%, respectively.
2. ProtecT study (Hamdy et al. NEJM 2016) – 20% of the active monitoring arm had Gleason 7-10 prostate cancer. Despite this, over a 10-year period, there was very little prostate cancer death! Patients do well on active monitoring.
3. Sunnybrook (Klotz et al. JU 2016) – patients with Gleason 6 disease did very well. However, patients with Gleason 7 disease (especially Gleason 4+3=7 or PSA >20) did poorly with unacceptable metastases rates.
The PRIAS-Japan study includes 39 institutions in Japan since initiation in 2010. It has accrued 841 men so far, ~100/year. Median PSA at enrollment 5.28, 90% cT1, 97% Gleason 6 (1% Gleason 5 and 1% Gleason 7), 75% were just 1 core positive.
First, he looked at the re-biopsy data at 1 year and 4-years. Both flowsheets are listed below:
1 year:
- Of 658 men who continued on AS at 1 year, 82.5% agreed to repeat biopsy
- Of these, 26.8% were reclassified. Some based on volume alone, some due to grade progression, and most due to both!
- Of 185 men who continued on AS at 4 year, only 60.5% agreed to repeat biopsy at 4 years
- Of these, 22.3% were reclassified. Some based on volume alone, some due to grade progression, and some due to both
- Interestingly, reclassification rate was similar to the one at 1 year
1. Positive core rate was the strongest predictor of reclassification
2. PSA doubling time was not associated with reclassification and cannot predict pathologic findings accurately
In the PRIAS-Japan study, the retention rate on AS is 69% at 2-years and 49% at 5-years. For those men who do move onto secondary treatment after AS, radical prostatectomy is the most common treatment (~36%), followed by LDR (20%), EBRT (19%), ADT (12%). 9% go on to watchful waiting!
Lastly, they also assessed quality of life results while on AS. This data was a little less concrete. Basic take-home – the QOL of men on AS was better than the general population at enrollment, and was maintained over follow-up (especially mental component). There was a deterioration in the physical component at around year 3. But, more work is required!
Presented by: Mikio Sugimoto, Japan
References:
1. Tosoian et al JCO 2015
2. Hamdy et al. NEJM 2016
3. Klotz et al. JU 2016
4. Sugimoto et al. World J. Urol 2015
Written By: Thenappan Chandrasekar, MD, Clinical Instructor, Thomas Jefferson University Twitter: @tchandra_uromd, @TjuUrology at the 38th Congress of the Society of International Urology - October 4- 7, 2018 - Seoul, South Korea