"The primary finding and perhaps most exciting aspect to this prospective study was the high rate of primary tumor control (97.6 percent at 3 years). Primary tumor control is an essential requirement for the cure of lung cancer. Stereotactic body radiation therapy as delivered in RTOG 0236 provided more than double the rate of primary tumor control previous reported for conventional radiotherapy suggesting that this technique could provide a significant step forward in the battle against this type of lung cancer," said Robert Timmerman, MD, of the University of Texas Southwestern Medical Center, Dallas, principal investigator on the RTOG study.
Currently, patients with inoperable early stage lung cancer are generally offered conventional radiation treatment (most commonly given during 20-30 outpatient treatments) or observed without specific cancer therapy. However, study authors indicate that neither of these approaches achieves ideal outcomes.
"Conventional radiotherapy fails to provide long-term control of the primary lung tumor in approximately two-thirds (60 percent to 70 percent) of patients. Most ultimately die specifically from progressive lung cancer with observation, and 2-year survival is less than 40 percent with either approach. Our study suggests that stereotactic body radiation therapy is a new option that produces better outcomes and may represent an updated, and ultimately more successful, approach to the treatment of patients with early stage inoperable lung cancer," said Timmerman.
This is the first North American multicenter, cooperative group study to test SBRT in treating medically inoperable patients with early stage non-small cell lung cancer. Dr. Timmerman and RTOG member investigators enrolled 59 patients to this phase II study that included patients 18 years or older with biopsy-proven peripheral T1-T2N0M0 non-small cell tumors (measuring less than 5 cm. in diameter) and medical conditions that would not allow surgical treatment. Radiation treatment lasted between 1.5 and 2 weeks. The study opened May 2004 and closed October 2006, with data analyzed through August 2009. The final study population included 55 evaluable patients (44 with T1 tumors and 11 patients with T2 tumors), with a median (midpoint) follow-up of 33.4 months.
The primary outcome measured for the study was 2-year actuarial primary tumor control; secondary end points were disease-free survival (i.e., primary tumor, involved lobe, regional, and disseminated recurrence [the reappearance or return of a cancer in multiple areas of the body]), treatment-related toxicity, and overall survival.
Of all the patients in the study, only one experienced a documented tumor recurrence or progression at the primary site. The 3-year primary tumor control rate was 97.6 percent. Three patients had recurrence within the involved lobe; the 3-year primary tumor and involved lobe (local) control rate was 90.6 percent. Combining local and regional failures, the 3-year local-regional control rate was 87.2 percent. Disseminated recurrence as some component of recurrence was reported in 11 patients. The 3-year rate of disseminated failure was 22.1 percent with 8 such failures occurring prior to 24 months.
Disease-free survival and overall survival at 3 years were 48.3 percent and 55.8 percent, respectively. Median disease-free survival and overall survival for all patients were 34.4 months and 48.1 months, respectively. Seven patients (12.7 percent) and two patients (3.6 percent) were reported to experience protocol-specified treatment-related grade 3 and 4 adverse events, respectively. No grade 5 treatment-related adverse events were reported. Higher grades indicate greater severity of adverse event, with grade 5 indicating death.
"While this is a phase II study involving a relatively small patient sample, these results suggest that this technique could greatly improve survival rates for patients with inoperable non-small cell lung cancer. For this group of patients there simply has not been significant advance in survival rates in some time. These results certainly dictate that further study of SBRT is warranted. We are optimistic that the technique holds promise for these patients," said Timmerman
According to Walter J. Curran, Jr., MD, the RTOG Group Chair, and the Executive Director of the Winship Cancer Institute of Emory University, "RTOG 0236 demonstrated that technologically intensive treatments like SBRT can be performed in the cooperative group setting so long as effective quality control measures are in place to assure patient safety. As the preeminent group conducting multi-institutional clinical trials of novel radiation therapy techniques, RTOG is building on these results to improve patient outcomes and quality of life with trials designed to address the rather high rate of disseminated failure observed after treatment, determine a safe and effective dose for central lung tumors, and refine the dose of SBRT for peripheral tumors."
RTOG is a National Cancer Institute-funded national clinical trials group and is administered by the American College of Radiology.
The Radiation Therapy Oncology Group (RTOG) is administered by the American College of Radiology (ACR), and located in the ACR Center for Clinical Research in Philadelphia, PA. RTOG is a multi-institutional international clinical cooperative group funded primarily by National Cancer Institute grants CA21661, CA32115 and CA37422. RTOG has 40 years of experience in conducting clinical trials and is comprised of over 300 major research institutions in the United States, Canada, and internationally. The group currently is currently accruing to 40 studies that involve radiation therapy alone or in conjunction with surgery and/or chemotherapeutic drugs or which investigate quality of life issues and their effects on the cancer patient.
The American College of Radiology (ACR) is a national professional organization serving more than 32,000 radiologists, radiation oncologists, interventional radiologists and medical physicists with programs focusing on the practice of radiology and the delivery of comprehensive health care services.
Shawn Farley | EurekAlert!
UCLA engineers use deep learning to reconstruct holograms and improve optical microscopy
22.11.2017 | University of California - Los Angeles
First transcatheter implant for diastolic heart failure successful
16.11.2017 | The Ohio State University Wexner Medical Center
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
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...
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...
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....
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,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
22.11.2017 | Medical Engineering
22.11.2017 | Materials Sciences
22.11.2017 | Health and Medicine