The role of early hormone therapy: it’s not good news for patients
Posted Sep 28 2008 1:49pm
According to a large retrospective data analysis published today in the Journal of the American Medical Association, “Primary androgen deprivation therapy is not associated with improved survival among the majority of elderly men with localized prostate cancer when compared with conservative management.” In other words, early hormone therapy offers no survival benefit over hormone therapy that is delayed until symptoms of the disease are apparent.
In discussing this article, the lead author, Dr. Grace Lu-Yao, is quoted as saying, “The finding itself was a little surprising because we know that hormones are effective in men with advanced disease or disease that’s spread beyond the prostate.” She went on to state that more men with early-stage prostate cancer are being given hormone therapy, despite the fact that there are no studies to show that it is beneficial for this patient population. The full study report is available on line.
The study looked at data from 19,271 men aged 66 years or older receiving Medicare who did not receive definitive local therapy for clinical stage T1-2 prostate cancer. The patients were all diagnosed between 1992 and 2002 in predefined US geographical areas, and were followed through December 31, 2006, for all-cause mortality and through December 31, 2004, for prostate cancer–specific mortality.
The results of the study are as follows:
Among patients initially diagnosed with localized prostate cancer (median age, 77 years), 7,867 (41 percent) received primary androgen deprivation (PADT), and 11,404 were treated with conservative management, not including PADT.
During the follow-up period, there were 1,560 prostate cancer-specific deaths and 11,045 deaths from all causes.
Primary androgen deprivation therapy was associated with a lower 10-year prostate cancer–specific survival (80.1 vs 82.6 percent)
There was no increase in 10-year overall survival (30.2 vs 30.3 percent) compared with conservative management.
Use of PDAT in men with poorly differentiated cancer was associated with a small improvement in prostate cancer–specific survival (59.8 vs 54.3 percent) but not overall survival (17.3 vs 15.3 percent).
In contrast to Dr. Lu-Yao’s statement, The “New” Prostate Cancer InfoLink does not find these results surprising. Only one, very small study has ever shown a survival benefit associated with the early use of hormonal therapy, and this study has always been the subject of fierce debate. The population under treatment here was a population diagnosed with early stage disease who did not receive radical therapy for early stage disease. We have known for years that the most significant impact of androgen deprivation is palliative. It impacts the pain associated with metastases to the bones. A survival benefit has never been categorically demonstrated.
Having said that we are not surprised by this result, we should add that we are disappointed. The implication is that the value of early hormone therapy is truly limited to men with progressive, high-grade cancer and men who combine radiotherapy with hormone therapy to delay progression of regionally progressive prostate cancer. It is highly likely that (at least in the USA) these data will be interpreted by Medicare and commercial payers as a justification to refuse coverage for androgen deprivation therapy until there is clear documentation of bone metastases.
We know that a rising PSA is a key issue of concern for many men with progressive prostate cancer. It is a clear sign that the disease is not well controlled. By managing their PSA levels with androgen deprivation therapy patients have, over the past two decades, been able to give themselves the sense that they might be impacting their survival. Now there are data to tell us that this may not be the case. However, and it is a BIG however, this trial is a retrospective analysis as opposed to a prospective trial. Regardless of how well this analysis was conducted, it cannot substitute for a large, well-designed, randomized, double-blind study in a well-controlled patient population. Whether such a trial can be justified is a different question.
We should note, as an aside, that this study shows an additional result not featured prominently by the authors in their conclusion. As indicated above:
There were 1,560 prostate cancer-specific deaths and 11,045 deaths from all causes.
The implication of these data is that only 8 percent of the patients in this study actually died of prostate cancer, whereas 57 percent died of other causes within the study follow-up period. The remaining 35 percent of patients were still alive at the last date of follow-up. Someone is certainly going to suggest that delaying the use of hormone therapy may have had a significant positive impact on the quality of life of many patients in this study because they were able to avoid all of the adverse effects of hormone therapy, from impotence and weight gain to gynecomastia. The “New” Prostate Cancer InfoLink would only note that (at least for some men) that particular benefit may be vastly outweighed by the knowledge that one has a serious progressive disease.