Patient-Specific Quality Assurance for Prostate Cancer Patients Receiving Spot Scanning Proton Therapy Using Single-Field Uniform Dose

Journal Article · Sat Oct 01 00:00:00 EDT 2011 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2010.11.071· OSTI ID:21587743

Poenisch, Falk; Song, Xiaofei; Johnson, Jennifer L; Ciangaru, George; Taylor, M Brad; Lii, Ming Fwu; Martin, Craig; Arjomandy, Bijan ^[1]; Lee, Andrew K; Choi, Seungtaek; Nguyen, Quynh nhu ^[2]; Gillin, Michael T; Sahoo, Narayan ^[1]

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1. Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)
2. Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)

Purpose: To describe our experiences with patient-specific quality assurance (QA) for patients with prostate cancer receiving spot scanning proton therapy (SSPT) using single-field uniform dose (SFUD). Methods and Materials: The first group of 249 patients with prostate cancer treated with SSPT using SFUD was included in this work. The scanning-beam planning target volume and number of monitor units were recorded and checked for consistency. Patient-specific dosimetric measurements were performed, including the point dose for each plan, depth doses, and two-dimensional (2D) dose distribution in the planes perpendicular to the incident beam direction for each field at multiple depths. The {gamma}-index with 3% dose or 3-mm distance agreement criteria was used to evaluate the 2D dose distributions. Results: We observed a linear relationship between the number of monitor units and scanning-beam planning target volume. The difference between the measured and calculated point doses (mean {+-} SD) was 0.0% {+-} 0.7% (range, -2.9% to 1.8%). In general, the depth doses exhibited good agreement except at the distal end of the spread-out Bragg peak. The pass rate of {gamma}-index (mean {+-} SD) for 2D dose comparison was 96.2% {+-} 2.6% (range, 90-100%). Discrepancies between the measured and calculated dose distributions primarily resulted from the limitation of the model used by the treatment planning system. Conclusions: We have established a patient-specific QA program for prostate cancer patients receiving SSPT using SFUD.

• OSTI ID: 21587743
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Vol. 81, Issue 2; Other Information: DOI: 10.1016/j.ijrobp.2010.11.071; PII: S0360-3016(10)03702-8; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BRAGG CURVE
DEPTH DOSE DISTRIBUTIONS
NEOPLASMS
PROSTATE
QUALITY ASSURANCE
RADIATION DOSES
RADIOTHERAPY
BODY
DIAGRAMS
DISEASES
DOSES
GLANDS
INFORMATION
MALE GENITALS
MEDICINE
NUCLEAR MEDICINE
ORGANS
RADIATION DOSE DISTRIBUTIONS
RADIOLOGY
SPATIAL DOSE DISTRIBUTIONS
THERAPY