G Sherouse | PubMed Health

PubMed1994

Portable software tools for 3D radiation therapy planning.

PURPOSE: Produce a collection of software tools (computer programs) that support three-dimensional (3D) radiation therapy planning. The tools are not a complete 3D planning system. Instead, they work with any 3D planning system that meets certain minimal specifications. The tools assist in deriving anatomic data from images, generating target volume contours, evaluating treatment plans, and verifying accurate treatment delivery. The tools are portable: they can run without source code changes in any computing environment that provides a library of functions and data definitions called the Foundation. The Foundation couples the portable tools to the (usually nonportable) file system and dose calculation associated with a particular 3D planning system. METHODS AND MATERIALS: Tools were written at three different (geographically separated) institutions. Software developers from all three sites specified the Foundation. The programmers' interface to the Foundation is portable, but a Foundation implementation need not be portable. Each group implemented a Foundation adapted to the (different) 3D planning system used at their site. RESULTS: All tools run at all three sites without source code changes. Each Foundation was implemented in a few person-months of programming effort. The program text and documentation for the tools have been placed in the public domain. CONCLUSIONS: It is practical and economical to produce portable radiotherapy treatment planning tools. Providers of 3D planning programs should offer Foundations for their systems, so they can be used with tools. Researchers considering new computer programs should write them as tools, so they can work with any 3D planning system.

Costs and Cost Analysis↗

PubMed1994

Changes in plasma TGF beta levels during pulmonary radiotherapy as a predictor of the risk of developing radiation pneumonitis.

PURPOSE: To determine whether plasma transforming growth factor-beta (TGF-beta) levels measured before and during radical radiotherapy for lung cancer could be used to predict patients at risk for the development of radiation pneumonitis. METHODS AND MATERIALS: The first eight patients with lung cancer (nonsmall cell: seven, small cell: one) enrolled in a prospective study designed to evaluate physiological and molecular biologic correlates of radiation induced normal tissue injury are described. The study began in June 1991. All patients were treated with radiotherapy with curative intent. Plasma transforming growth factor-beta levels were obtained before, weekly during, and at each follow-up after treatment. Pretreatment pulmonary function tests and single photon emission computed tomography scans were obtained to assess baseline lung function and were repeated at follow-up visits. Dose-volume histogram analyses were performed to determine the volume of lung which received > or = 30 Gy. Patients were assessed at each follow-up visit for signs and symptoms of pneumonitis. RESULTS: Five patients developed signs and/or symptoms of pulmonary injury consistent with pneumonitis and three patients did not. In all three patients not developing pneumonitis, plasma TGF-beta levels normalized by the end of radiotherapy. In contrast, four out of five patients who suffered pneumonitis had persistently elevated plasma TGF-beta levels by the end of therapy. This finding appeared to be independent of the volume of irradiated lung. CONCLUSIONS: These results suggest that plasma TGF-beta levels during treatment may be useful to determine which patients are at high risk of developing symptomatic pneumonitis following thoracic radiotherapy. This finding may have implications when planning additional therapy (either chemotherapy or radiotherapy) which may have potentially adverse consequences on the lung.

Adult↗