Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Intermittent hormone therapy for prostate cancer inferior to continuous therapy

04.06.2012
Overall survival times shorter for many patients

Many men with metastatic, hormone-sensitive prostate cancer live longer on continuous androgen-deprivation therapy (also known as hormone therapy) than on intermittent therapy, according to a seventeen-year study led by SWOG, a cancer research cooperative group funded by the National Cancer Institute (NCI).

Men with newly diagnosed metastatic prostate cancer are usually either surgically castrated or given medications to suppress the production of male hormones that drive their cancer. The treatment can help keep the disease at bay temporarily, but in the majority of patients the cancer will relapse and contribute to the patient's death.

Surgical castration is permanent but "medical castration" provides men the potential advantage of receiving therapy intermittently. A halt in this therapy is followed in time by a rise in testosterone levels. Scientific data suggested that intermittent treatment may delay the cancer relapse, and that the rise in testosterone may result in an improvement in the patient's quality of life.

These data provided the rationale for the phase III clinical trial SWOG-9346, the largest such study to date in men with metastatic, hormone-sensitive disease. Results of this study demonstrate that intermittent androgen-deprivation (AD) therapy is not as good as continuous hormone therapy with regard to patient longevity.

The findings are to be presented today at the plenary session of the American Society for Clinical Oncology's (ASCO's) annual meeting by the study's principal investigator, Maha Hussain, M.D., F.A.C.P., of the University of Michigan Comprehensive Cancer Center.

"Based on these results," Hussain says, "we can conclude that intermittent AD is not as effective as continuous AD in men with metastatic prostate cancer."

Clinical researchers from the SWOG network, with funding from the NCI, led an international team in conducting the study at more than 500 sites, enrolling 3,040 men with hormone-sensitive, metastatic prostate cancer between 1995 and 2008.

All men got an initial course of androgen-deprivation treatment for seven months. The 1,535 eligible men whose prostate-specific antigen (PSA) level dropped to 4 ng/mL or less by the end of those seven months were then assigned at random to stop therapy (the intermittent therapy group) or continue therapy (the continuous therapy group).

Those randomized to the intermittent therapy arm had their treatment suspended until their PSA rose to a predetermined level, at which time they started another seven-month course of androgen-deprivation therapy, cycling on and off therapy in this way as long as their PSA levels continued to respond appropriately during the "on" cycle.

Men on continuous therapy had a median overall survival time of 5.8 years from the time of randomization, with 29 percent of these men surviving at least 10 years. Those on intermittent therapy had a median overall survival time of 5.1 years, with 23 percent surviving at least 10 years from the time they were randomly assigned to a treatment arm.

The researchers found, in additional analyses, that men with "minimal disease" (disease that had not spread beyond the lymph nodes or the bones of the spine or pelvis) did significantly better on continuous therapy, while men with "extensive disease" (disease that had spread beyond the spine, pelvis, and lymph nodes or to the lungs or liver) seemed to do about as well using either treatment approach.

Additional analyses indicated that the median overall survival time for those with minimal disease was 7.1 years on continuous androgen-deprivation therapy compared to only 5.2 years on intermittent treatment. Patients with extensive disease had median overall survival times of 4.4 years on continuous therapy and 5.0 years on intermittent therapy.

"In the past when it came to using hormone therapy in this disease, doctors viewed the disease as one entity and adopted a 'one size fits all' approach," Hussain says. "Based on this study's findings, it seems that one size does not necessarily fit all."

Trial researchers also compared quality-of-life measures across the two study arms during the first 15 months following patient randomization, including measures of sexual function (impotence and libido), physical and emotional function, and energy level. They found improved sexual function in men who received intermittent therapy as compared to those on continuous therapy. A second presentation at an ASCO Poster Discussion session (morning of June 4th, Poster #25) reports on these preliminary quality-of-life findings from SWOG-9346 (Abstract #4571, CM Moinpour, DL Berry, et al).

"Though we see potential quality-of-life benefits with IAD," Hussain says, "from a medical perspective, the primary findings of the study demonstrating that IAD is inferior with regard to overall survival should be the primary consideration in counseling all patients who are interested in intermittent therapy and particularly those with minimal disease."

In brief: 1,535 men with metastatic, hormone-sensitive prostate cancer were randomized to intermittent androgen-deprivation (AD) therapy or continuous AD therapy after seven months of androgen deprivation.
When overall survival times were compared, intermittent AD was inferior to continuous AD.
For the subset of patients with minimal disease, continuous AD was superior to intermittent AD.
For patients with extensive disease, overall survival was comparable between intermittent and continuous AD.

A number of quality-of-life measures got higher scores in the intermittent AD arm than the continuous AD arm.

Prostate cancer statistics: More than 240,000 men in the United States will be diagnosed with prostate cancer in 2012, according to the American Cancer Society, and more than 28,000 will die of the disease.

Additional authors: CM Tangen, CS Higano, ED Crawford, G Liu, G Wilding, S Prescott, A Akdas, EJ Small, NA Dawson, BJ Donnelly, PM Venner, UN Vaishampayan, PF Schellhammer, DI Quinn, D Raghavan, N Vogelzang, IM Thompson, Jr.

Funding: National Cancer Institute; AstraZeneca Pharmaceuticals

Disclosure: None

Reference: Hussain, M et al, "Intermittent (IAD) vs Continuous Androgen Deprivation (CAD) in Hormone Sensitive Metastatic Prostate Cancer (HSM1PC) Patients (pts): Results of S9346 (INT-0162) an International Phase III Trial." American Society of Clinical Oncology Annual Meeting, June 1-5, 2012, Chicago, abstract No. 4.

ClinicalTrials.gov identifier: NCT00002651

About the SWOG clinical trials network:

SWOG is one of the five cooperative groups that together comprise the National Cancer Institute's (NCI's) National Clinical Trials Network. The group designs and conducts multidisciplinary clinical trials to improve the practice of medicine in preventing, detecting, and treating cancer, and to enhance the quality of life for cancer survivors. The more than 4,000 researchers in the group's network practice at more than 500 institutions, including 22 of the NCI-designated cancer centers as well as cancer centers in almost a dozen other countries. Formerly the Southwest Oncology Group, SWOG is headquartered at the University of Michigan in Ann Arbor (734-998-7140) and has an operations office in San Antonio and a statistical center in Seattle. Learn more at swog.org.

SWOG – Leading cancer research. Together.

Frank DeSanto | EurekAlert!
Further information:
http://www.umich.edu

More articles from Health and Medicine:

nachricht NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures
17.11.2017 | National Institute of Standards and Technology (NIST)

nachricht High speed video recording precisely measures blood cell velocity
15.11.2017 | ITMO University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Antarctic landscape insights keep ice loss forecasts on the radar

20.11.2017 | Earth Sciences

Filling the gap: High-latitude volcanic eruptions also have global impact

20.11.2017 | Earth Sciences

Water world

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>