Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Improved diagnostic test benefits children with acute myeloid leukemia

11.09.2012
St. Jude Children’s Research Hospital study identifies the best test for determining treatment response in young leukemia patients, which could help guide therapy toward higher cure rate

Early treatment response is a powerful predictor of long-term outcome for young patients with acute myeloid leukemia (AML). The information can help physicians decide whether a more intensive approach is needed. Research led by St. Jude Children’s Research Hospital investigators has identified the best test for measuring that response and guiding therapy.

The method uses a laboratory technique called flow cytometry, which makes it possible to identify a single cancer cell in 1,000 normal cells that remain in patient bone marrow after the initial intensive weeks of chemotherapy. St. Jude investigators were instrumental in developing the test for identifying very low levels of cancer called minimal residual disease.

An analysis published in the September 10 online edition of the Journal of Clinical Oncology showed that checking for minimal residual disease by flow cytometry was better than two other widely used methods for predicting patient survival. The results help identify who might benefit from more intensive therapy, including bone marrow transplantation.

“These results will help establish flow cytometry testing for minimal residual disease as a routine tool for guiding therapy of acute myeloid leukemia and identifying patients early who are at risk of treatment failure,” said Hiroto Inaba, M.D., Ph.D., an associate member of the Department of Oncology at St. Jude. He is the study’s first and corresponding author.

Flow cytometry uses a laser to help distinguish cancer cells from normal cells based on different cell surface markers and other molecules. Dario Campana, M.D., Ph.D., led the successful St. Jude effort to develop the test about 15 years ago. Campana, now at the National University of Singapore, is the paper’s senior author.

Such testing is widely used to guide treatment of the most common childhood cancer, acute lymphoblastic leukemia (ALL). AML targets different white blood cells than ALL does. AML also affects fewer children and adolescents, about 500 annually in the U.S., and has a lower survival rate. Although 94 percent of St. Jude ALL patients can now look forward to becoming long-term survivors, the figure is 71 percent for young AML patients.

AML treatment response is evaluated on day 22 of therapy as well as at the end of each treatment phase and serves as a powerful predictor of patient survival. The results are used to guide ongoing therapy and identify patients who are candidates for more intense treatment.

For decades, physicians have relied on the microscope to evaluate patient response to therapy. Patients are considered to be in remission if a bone marrow examination finds cancer cells account for fewer than five in 100 cells. Flow cytometry and another laboratory technique called polymerase chain reaction (PCR) were also developed to help gauge treatment response. PCR is used to monitor genes created when chromosomes break and swap pieces. The genes are found in about half of all pediatric AML cases.

This study is the most comprehensive effort yet comparing the power of the three approaches to predict the AML treatment outcome. The work involved 203 AML patients enrolled in a clinical trial called AML02. St. Jude led the multi-institution study of young AML patients whose disease was diagnosed between 2002 and 2008. The project marked the first time minimal residual disease was used to guide therapy. During the study researchers examined 1,514 patient bone marrow samples by flow cytometry. Of those samples, 1,382 also had information regarding microscopic evaluation and 508 of PCR testing.

The analysis showed that minimal residual disease measured by flow cytometry was an independent predictor of patient outcome. Finding even one leukemia cell in 1,000 normal cells in bone marrow after the first or second round of therapy was associated with a worse prognosis and a greater risk of relapse or treatment failure.

Researchers concluded microscopic examination had limited value for gauging treatment response. Problems ranged from an inability to distinguish between cells destined to become leukemia cells and normal blood cells to classifying about 10 percent of patients as being in remission when flow cytometry identified leukemia cells in the same bone marrow.

Investigators also concluded that flow cytometry rendered PCR testing unnecessary for most AML patients. The analysis found PCR testing generally overestimated the presence of leukemia cells. In this study, PCR identified 197 of 311 patient samples as containing leukemia cells. Flow cytometry of the same samples showed just 19 actually harbored detectible minimal residual disease. Researchers did find PCR testing valuable in predicting outcome and guiding therapy for a subgroup of AML patients with mixed lineage leukemia (MLL) gene changes.

The other authors are Elaine Coustan-Smith, National University of Singapore; Xueyuan Cao, Stanley Pounds, Sheila Shurtleff, Susana Raimondi, Jeffrey Jacobsen, Raul Ribeiro, Wing Leung, James Downing, Ching-Hon Pui and Jeffrey Rubnitz, all of St. Jude; Kathleen Wang and Mihaela Onciu, both formerly of St. Jude; Gary Dahl, Lucile Packard Children’s Hospital and Stanford Cancer Center, Palo Alto, CA.; W. Paul Bowman, Cook Children’s Medical Center, Fort Worth; Jeffrey Taub, Children’s Hospital of Michigan, Detroit; and Barbara Degar, Dana-Farber Cancer Institute, Boston.

The research was supported in part by grants (CA115422, CA023944 and CA021765) from the National Cancer Institute at the National Institutes of Health and ALSAC.

St. Jude Children’s Research Hospital
Since opening 50 years ago, St. Jude Children’s Research Hospital has played a pivotal role in pushing overall U.S. pediatric cancer survival rates from 20 to 80 percent. Founded by the late entertainer Danny Thomas, St. Jude is the first and only National Cancer Institute-designated Comprehensive Cancer Center devoted solely to children. St. Jude is also a leader in research and treatment of life-threatening blood disorders and infectious diseases in children. No family ever pays St. Jude for the care their child receives. To learn more, visit www.stjude.org. Follow us on Twitter @StJudeResearch.

St. Jude Media Relations Contacts

Summer Freeman
(desk) 901-595-3061
(cell) 901-297-9861
summer.freeman@stjude.org
Carrie Strehlau
(desk) 901-595-2295
(cell) 901-297-9875
carrie.strehlau@stjude.org

Carrie Strehlau | EurekAlert!
Further information:
http://www.stjude.org

More articles from Health and Medicine:

nachricht A promising target for kidney fibrosis
21.04.2017 | Brigham and Women's Hospital

nachricht Stem cell transplants: activating signal paths may protect from graft-versus-host disease
20.04.2017 | Technische Universität München

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: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>