|
Molecular Therapeutics Advance Fight Against Brain
Cancer
New imaging and genetic techniques available only at Penn for state-of-the-art
approaches
to brain tumor treatment
(Philadelphia, PA) -- An estimated 41,000 new cases of primary brain
tumors are expected to be diagnosed in 2004, according to the American
Brain Tumor Association. To further narrow the gap between diagnosis and
effective therapy, physicians at the Hospital of the University
of Pennsylvania now offer several promising -- and unique to
the Philadelphia region -- approaches to brain tumor treatment, including
novel imaging for oncologic neurosurgery and refined genetic testing for
tumors to better target treatment.
Through enhanced magnetic resonance imaging (MRI), newer and broader information
is helping to better guide tumor removal. MRI is used to measure the anatomy
and metabolism of tumors. This informs surgeons pre- and post-operatively
with a three-dimensional map of tumor-associated blood flow to more precisely
assess the full extent of tumor growth versus conventional imaging methods.
“This novel approach helps guide surgery and assessment of treatment
response,” says Donald M. O’Rourke, M.D.,
Associate Professor of Neurosurgery. These novel imaging methods are leading
to increased patient survival by allowing for greater tumor removal in
a safe manner.
Neuroscientists are also ushering in a new era in which genetics will
dictate treatment. In the 1990s researchers noted that a more favorable
prognosis in patients with certain brain tumors, primarily oligodendrogliomas,
was associated with a deletion of genes on chromosomes 1 and 19. This
genetic loss translates into a significant life-expectancy gain for some
patients and is therefore a robust predictor that post-surgery chemotherapy
should be given to such patients.
Patients with the genetic deletion on chromosome 1 have a median survival
in certain cases of about 10 years and respond particularly well to chemotherapy
given immediately after surgery. Patients with the deletion have slower-growing
tumors and show a better response to chemotherapy; whereas, those without
the deletion have relatively faster-growing tumors and are less responsive
to chemotherapy, so radiation therapy is required sooner. “Given
the expected increase in the life-span of patients with this deletion,
there is no need to give radiation therapy early in their treatment,”
explains O’Rourke.
The deletion can only be detected by genetic analysis. “Under the
microscope these tumors can look identical, so there’s no way of
knowing the difference unless a genetic analysis is performed,”
explains O’Rourke.
Having the ability to provide such genetic testing to determine treatment
is of benefit to patients. “The idea of using a genetic test to
predict prognosis and select therapy, thereby deferring potentially deleterious
treatment is tremendously attractive,” says O’Rourke. “Penn’s
genetic testing is done in-house, so patients don’t have to wait
for the results.” Further, there is no cost to the patient at this
point since the tests are performed by the Neuro-oncology Program and
supported by the Abramson Cancer Center at Penn. In addition, there is
no requirement for additional blood samples, so results will be given
more quickly with no need for follow-up visits.
Penn colleagues J. Carl Oberholtzer, MD, PhD, Department
of Neuropathology and Myrna Rosenfeld, MD, PhD, Department
of Neurology and Director of the Division of Neuro-oncology as well as
Jaclyn Biegel, PhD, Director of Cytogenetics, Children’s
Hospital of Philadelphia, collaborated with O’Rourke on developing
the genetic testing program. Dr. Biegel’s laboratory performs the
genetic test and has significant experience with genetic testing of brain
tumors.
O’Rourke is also Director of the Human Brain Tumor Tissue Bank at
Penn, a unique resource to the region and one of only a few such dedicated
banks in the United States. Tissue banks allow for the direct evaluation
of human tumors and are one of the best ways to advance treatment options
for gliomas and other human cancers. O’Rourke’s basic research
interests include finding new treatments for gliomas based on genetic
alterations detected in tumors. He is currently investigating a variant
of the epidermal growth factor receptor that is present in many primary
glioblastomas to better understand the development of malignancy in the
brain and how it relates to cancer cell division, survival, and movement.
O’Rourke and colleagues are now prepared to discuss potential surgical
and clinical treatments and genetic evaluation of brain tumor patients.
Contact Dr. O’Rourke at 215-662-3490 for more information.
###
PENN Medicine is a $2.5 billion enterprise dedicated
to the related missions of medical education, biomedical research, and
high-quality patient care. PENN Medicine consists of the University of
Pennsylvania School of Medicine (founded in 1765 as the nation’s
first medical school) and the University of Pennsylvania Health System
(created in 1993 as the nation’s first integrated academic health
system).
Penn’s School of Medicine is ranked #3 in the nation for receipt
of NIH research funds; and ranked #4 in the nation in U.S. News &
World Report’s most recent ranking of top research-oriented medical
schools. Supporting 1,400 fulltime faculty and 700 students, the School
of Medicine is recognized worldwide for its superior education and training
of the next generation of physician-scientists and leaders of academic
medicine.
Penn Health System is comprised of: its flagship hospital, the Hospital
of the University of Pennsylvania, consistently rated one of the nation’s
“Honor Roll” hospitals by U.S. News & World Report; Pennsylvania
Hospital, the nation's first hospital; Presbyterian Medical Center; a
faculty practice plan; a primary-care provider network; two multispecialty
satellite facilities; and home health care and hospice. |