Srivastava reports radiology study
Shiv Srivastava, a Diplomate of the American Board of Radiology and a radiological physicist
at Reid Hospital & Health Care Services, has co-authored a study that has been presented
to the American Society for Therapeutic Radiology and Oncology (ASTRO) in the Boston Convention
and Exhibition Center in Massachusetts.
Srivastava's study, "Dosimetric Variability in Lung Cancer IMRT/SBRT among Institutions with Identical Treatment Planning Systems," was scheduled for presentation at the society's 50th annual meeting in Boston on Sept. 21-25, 2008.
"Lung cancer represents nearly a third of the cancer burden in the country, and treatment outcomes need to be improved," Srivastava said. "To improve outcomes, dose escalation is being proposed; however, clinical data lack dosimetric uniformity due to differences in treatment planning systems (TPS) and algorithms such as equivalent path length, pencil beam, collapsed cone and analytical anisotropic algorithm (AAA)."
According to Srivastava, the study compared the results obtained with similar treatment planning systems (TPS) at different institutions. Intra-TPS dosimetric variability proved to be extremely large and cannot justify comparison of outcome data among centers in a clinical trial.
The study concludes that AAA should be the algorithm of choice in Eclipse TPS and used over PB and EPL in lung treatment planning for IMRT/SBRT. The large intra-TPS variations could be reduced with proper CT to electron density table, smaller grid size and proper bench marking in small fields during TPS commissioning.
ASTRO's Annual Meeting is a premier scientific meeting in radiation oncology and is designed around the educational needs of radiation oncologists, physicists, biologists, nurses and other health care professionals in the field of radiation oncology, as well as oncologists in related specialties.
The research is published in the International Journal of Radiation Oncology and Biology/Physics and is available on-line at www.redjournal.org.