A new article in the Scandinavian Journal of Urology provides us with some insight — from relatively recent data — into the survival times of men with metastatic, castration-resistant prostate cancer (mCRPC) after prior treatment with androgen deprivation therapy (ADT) but who either decline or do not receive any further form of life-prolonging therapy.
The paper by Löffeler et al. is based on a retrospective analysis of data from an unselected cohort of consecutive patients with mCRPC, all seen at the urological unit of a single Swedish hospital from 2000 to 2005. All the patients had received prior treatment with ADT of various types and then had a rising PSA level while still on ADT.
The authors report the following data:
- Average (median) overall survival after diagnosis with mCRPC was 12.3 months (but the range was from 0.2 months to 9 years).
- Two patients were still alive at the end of the study follow-up period.
- 16.9 percent of the patients were alive at 3 years of follow-up.
- During the study follow-up period
- Men with a PSA nadir of < 1 ng/ml while on ADT were 71 percent less likely to die than men whose PSA nadir was > 11 ng/ml while on ADT.
- Men with a PSA doubling time of < 1.6 months during the early phase of mCRCP were almost three times more likely to die than men with a PSA doubling time > 3 months.
- Serum levels of alkaline phosphatase and hemoglobin levels within the normal range suggested a more favorable prognosis.
It is clear from these data that there remains a very wide range of survival times for men with mCRPC even when they receive no further life-extending form of treatment (e.g., abiraterone acetate, ezalutamide, docetaxel-based chemotherapy, etc.). This fact is important in the evaluation of data from the clinical trials of products that are hoped to demonstrate improvements in overall and prostate cancer-specific survival, and potentially in our understanding of why individual patients with specific disease characteristics may or may not benefit from such life-extending benefits.
What is also clear from these data is that it is the minority of patients who are going to have significant long-term survival after they become castration-resistant. The majority will die within about 12 months of the onset of castration-resistance unless they receive some form of life-extending treatment.
Filed under: Living with Prostate Cancer, Management, Treatment | Tagged: castration-resistant, mCRPC, metastatic, overall, survival, untreated |
THE "NEW" PROSTATE CANCER INFOLINK 
This is a tragic situation for those men and their loved ones. When hope is gone, we still have faith.
It seems to me that the wide range of survival times may be largely explained by the wide range of patient histories. This study evidently lumps patients diagnosed by PSA screening whose post-treatment PSA never exceeded 2 ng/ml with patients diagnosed with PSA of 400 ng/ml. It is no surprise that there is a wide range of survival times!
The abstract does not say how many patients were involved in this study. One would hope, if the number is large enough, that they could have stratified the results according to how advanced the cancer was at time of initiation of ADT.
Dear Tom:
Like you, I can only see the abstract of the original paper, not the full text. However, I would make a couple of observations.
(1) It is unlikely that anyone would have done a study like this if they couldn’t base it on at least 150+ patients.
(2) The authors clearly did investigate all sort of potential factors that might affect survival. They specifically mention two that did impact risk (as identified below). It actually seems unlikely to me that the patient’s absolute PSA level at time of diagnosis with mCRPC would be relevant by comparison with these two factors.
(3) Men whose PSA level was never lower than 11 ng/ml while they were initially on ADT (and before they became castration-resistant) had a 71% higher death rate than the men whose PSA dropped to < 1 ng/ml while they were on ADT.
(4) Men with a PSA doubling time of less than 1.6 months during the earliest phase of mCRCP had a risk of death almost three times higher than men with a PSA doubling time longer than 3 months during the same early phase of mCRPC.