A new study from Fox Chase Cancer Center finds that higher doses of 74 to 82 Gray (Gy) greatly reduce the risk that the cancer will spread later--even 8-10 years after treatment. The results of the study were presented today at the 48th Annual Meeting of the American Society for Therapeutic Radiology and Oncology in Philadelphia.
"There is a comprehensive body of evidence demonstrating that prostate cancer treated with higher doses of radiation is less likely to grow back in the prostate or cause a rising PSA, and now, we know it is also less likely to spread later to other parts of the body," explained Peter Morgan, M.D., a resident in the Radiation Oncology Department at Fox Chase Cancer Center.
Generally, treatment centers that offer 3D conformal radiation therapy or a newer system of radiation delivery called IMRT (intensity modulated radiation therapy) treat men with the higher levels of radiation shown in this study to prevent the cancer's spread.
Morgan said that no published data from prospective randomized trials have shown a significant reduction in distant metastasis with higher radiation dose, likely because patients have not been followed for long enough to see the reduced of late-wave of metastasis. The current study shows that the risk of cancer spreading 8-10 years after treatment is lower when doses >74 Gray of radiation are given.
When asked how more radiation to the prostate protects the rest of the body from the cancer, Dr. Morgan replied, "That's what is so important about this work. We believe that the late wave of distant metastasis is due to the persistence of cancer in the prostate itself, which subsequently seeds tumor cells to other parts of the body. Because higher dose radiation more effectively kills cancer in the prostate, the source for future metastases is eliminated."
From 1989 to 1999, 667 men with intermediate- to high-risk prostate cancer were treated consecutively with 3D conformal radiation therapy. The outcomes of men who received less than 74 Gy, 74-75.9 Gy and greater than 76 Gy were compared. These groups had a median follow-up of 84, 84 and 65 months, respectively. The 10-year rate of the cancer spreading outside of the prostate (distant metastasis) was 16 percent for radiation doses less than 74 Gy, 7 percent for 74-75.9 Gy, and 3 percent for greater than 76 Gy.
Morgan said, "At our institution the policy for several years has been to treat prostate cancer to a dose of 76 to 80 Gy using IMRT. This study confirms that we are doing the right thing."
Karen Mallet | EurekAlert!
Advanced analysis of brain structure shape may track progression to Alzheimer's disease
26.10.2016 | Massachusetts General Hospital
Indian roadside refuse fires produce toxic rainbow
26.10.2016 | Duke University
Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.
So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
28.10.2016 | Power and Electrical Engineering
28.10.2016 | Physics and Astronomy
28.10.2016 | Life Sciences