Investigation of the Attila Deterministic Solver for Out-of-Field Organ Dose Calculations for Radiotherapy Patients

Journal Article · Wed Jun 15 04:00:00 EDT 2016 · Transactions of the American Nuclear Society

OSTI ID:22991819

Mille, Matthew; Lee, Choonsik ^[1]

---

1. Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20850 (United States)

An undeniable paradox in the current practice of radiation oncology is that the therapeutic radiation often used to treat cancer is also a known carcinogen. Indeed, the potential for inducing second cancers in patients receiving radiotherapy has been well established. Retrospective epidemiological studies are an important way to assess the risks of late effects in radiotherapy patients. Such investigations attempt to correlate organ dose with the incidence of secondary cancers in a cohort of patients. Individualized patient dosimetry is a critical component of these studies and is challenging for two reasons. First, medical images describing the patient's anatomy are either non-existent or, if they exist, often only cover a portion of the body. This means that whole body computational human phantoms must be used as a surrogate for the patient's true anatomy in order to perform dose calculations far from the treatment site. Second, the gold standard dosimetry approach calls for the use of Monte Carlo radiation transport simulations which are far too slow for studies involving large-scale patient cohorts. This paper describes a preliminary effort at the National Cancer Institute aimed at addressing these dosimetry challenges. The Attila software (Varian Medical Systems, Palo Alto, CA) is investigated as an alternative to Monte Carlo for performing out-of-field organ dose calculations for radiotherapy patients. Whereas as Monte Carlo uses stochastic methods, Attila can deterministically solve the linear Boltzmann equation throughout the entire solution space. It is hypothesized that dose calculations with Attila will offer comparable accuracy to Monte Carlo, but with significant faster computation times. At least one study has demonstrated this for in-field dose calculations [3]. To our knowledge Attila has not yet been used to perform out-of-field organ dosimetry. (authors)

• OSTI ID: 22991819
• Journal Information: Transactions of the American Nuclear Society, Journal Name: Transactions of the American Nuclear Society Journal Issue: 1 Vol. 114; ISSN 0003-018X
• Country of Publication: United States
• Language: English

Related Subjects

61 RADIATION PROTECTION AND DOSIMETRY
62 RADIOLOGY AND NUCLEAR MEDICINE
ANATOMY
BOLTZMANN EQUATION
DOSIMETRY
MONTE CARLO METHOD
NEOPLASMS
ORGANS
PHANTOMS
RADIATION TRANSPORT
RADIOTHERAPY
SIMULATION
STOCHASTIC PROCESSES
THERAPEUTIC DOSES