Older Prostate Cancer Patients' Chances Improved in 1990s
Treatments - Active Surveillance
Tuesday, 15 September 2009 00:00
In Screening Era, More Elderly Men Have Survived Prostate Cancer on "Watchful Waiting"
Older men who were diagnosed with prostate cancer after early 1990 and were treated with conservative management ("Watchful Waiting") lived significantly longer than men in similar situation ten or twenty years previous to that.
This is the finding of a large new study based on Medicare patients' records. The study is published in September 15 issue of the Journal of the American Medical Association (JAMA) by a team at The Cancer Institute of New Jersey (CINJ).
Most newly diagnosed prostate cancers today have clinically localized disease, detected by the PSA test (Prostate Specific Antigen blood test) and digital rectal exam in the doctor's office.
For men with localized disease major treatment options include surgery, radiation, or conservative management (popularly known as "Watchful Waiting," also called Active Surveillance).
Especially for older men with competing health conditions such as diabetes or cardiovascular disease, conservative management can be a reasonable choice. Between 56 and 60 percent of men in this study (depending on tumor grade) had a risk of dying of causes other than prostate cancer within ten years following diagnosis.
The early 1990s saw the start of significant changes and improvements in methods of diagnosing, classifying and treating prostate cancer. Some of these changes have remained controversial to this day.
Dr. Grace L. Lu-Yao and colleagues say outcomes for conservative management in the era since the prostate-specific antigen (PSA) became available had not been fully assessed. s Dr. Lau-Yao's study is one of the largest and most reliable studies to affirm that overall, changes overall had a positive impact. She says the team's findings may lead to reassessment of treatment options for localized prostate cancer.
A Medicare records database was used to find out what happened to 14,516 men aged 66 or older who were diagnosed with with stage T1 or T2 prostate cancer cancer from 1992 through 2002 and who did not receive surgery or radiation within six months of diagnosis.
The study found that for patients in this category the risk of dying from prostate cancer over a ten-year period after diagnosis declined by more than 60 percent compared with patients diagnosed in the 1970s and 1980s. A prostate cancer patient's risk of dying from prostate cancer over a ten-year period following diagnosis declined by more than 60 percent compared with patients diagnosed in the two previous decades, the study found.
For example, among patients with medium-risk cancer, men aged 66 to 74 had between a 2 and 6 percent chance of dying from prostate cancer within ten years compared to 15 to 23 percent in the earlier period.
"Improved survival was also observed in poorly differentiated disease. The use of chemotherapy (1.6%) or major interventions for spinal cord compression (0.9%) was uncommon."
The authors say the improvement in survival rates since the early 1990's could relate to such factors as:
- earlier diagnosis due to the increased use of the PSA blood test
- changes in how disease is classified
- and advances in medical care
The study also showed that men aged 66 and older with low- to intermediate-risk cancer without initial surgery or radiation have a low risk of needing palliative therapy. Only 4 to 11 percent of men in this group used palliative surgery, radiation, or chemotherapy to alleviate pain or cancer symptoms over a ten-year period following diagnosis.
Grace Lu-Yao, PhD, the lead author, notes that previously the survival outlook for prostate cancer, especially disease detected through the PSA test, has not been well described. The study by her team represents the most comprehensive look at this subject to date, she says.
"The lack of solid data has often made it difficult for medical professionals to determine the most appropriate treatment and to predict patient outcomes for this population. These latest findings depict a more accurate survival outcome for the contemporary prostate patient," she noted.
The improved survival reported in JAMA is in line with findings of another study, to be published September 16 by some of the same authors in the Journal of the National Cancer Institute (JNCI) (Volume 101, Issue 18), which documents significant changes in the risk profile of prostate cancer patients diagnosed and treated today.
One unique feature of Dr. Lu-Yao's study is that more than half of the patients were over age 78. Men of this age merit special study because of their particular situation. The rate of prostate cancer rises in men of 75 years and older, but by this age men often have other health conditions to contend with also. This makes age 75 and older prime candidates for conservative management (or intelligent "Watch and Wait").
According to Dr. Lu-Yao, not enough information has been collected on this group of patients because in previous studies they have often been excluded or under-represented.
Lu-Yao cautions that because the men in the study were older than 65, the data may not apply to younger patients. She also notes that longer follow-up data are needed for prostate patients who are expected to live for more than ten years.
For this study the researchers made use of stored information from cancer registries and healthcare visit data collected by Medicare and known as SEER -- Surveillance, Epidemiology and End Results. All of the SEER registries hold the highest level of certification of data quality.
Prostate cancer is the second leading cause of cancer death in men and strikes one in six men. In New Jersey alone, 6,000 new cases of the disease are expected this year with 192,000 new cases nationally.
The study, Outcomes of Localized Prostate Cancer Following Conservative Management, appears in Journal of the American Medical Association (JAMA) (Vol. 302, No. 11). Authors are: Grace L. Lu-Yao, MPH, PhD; Peter C. Albertsen, MD; Dirk F. Moore, PhD; Weichung Shih, PhD; Yong Lin, PhD; Robert S. DiPaola, MD; Michael J. Barry, MD; Anthony Zietman, MD; Michael O’Leary, MD, MPH; Elizabeth Walker-Corkery, MPH; Siu-Long Yao, MD.Grace Lu-Yao, PhD, MPH is both the lead author of the JAMA study and the senior author of another study on this topic published in Journal of the National Cancer Institute (JNCI study. Dr. Lu-Yao is cancer epidemiologist at CINJ, a Center of Excellence of UMDNJ-Robert Wood Johnson Medical School. Dr. Lu-Yao is also associate professor of medicine at UMDNJ-Robert Wood Johnson Medical School and of epidemiology at UMDNJ-School of Public Health
The study was paid for in part by the U.S. Army Medical Research team at Department of Defense, by Ohl Foundation, National Cancer Institute (R01 CA 116399), and by The Cancer Institute of New Jersey Core Grant (NCI-CA-72720-10).
