A Comparison of Dose-Response Models for the Parotid Gland in a Large Group of Head-and-Neck Cancer Patients

Journal Article · Mon Mar 15 04:00:00 EDT 2010 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2009.07.1685· OSTI ID:21372188

Philippens, Marielle E.P.; Dijkema, Tim; Roesink, Judith M ^[1]; Terhaard, Chris H.J. ^[2]; Schilstra, Cornelis; Ten Haken, Randall K; Eisbruch, Avraham ^[3]; Raaijmakers, Cornelis P.J. ^[1]

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1. Department of Radiotherapy, University Medical Center Utrecht, Utrecht (Netherlands)
2. Department of Radiation Oncology, University Medical Center Groningen, Croningen (Netherlands)
3. Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)

Purpose: The dose-response relationship of the parotid gland has been described most frequently using the Lyman-Kutcher-Burman model. However, various other normal tissue complication probability (NTCP) models exist. We evaluated in a large group of patients the value of six NTCP models that describe the parotid gland dose response 1 year after radiotherapy. Methods and Materials: A total of 347 patients with head-and-neck tumors were included in this prospective parotid gland dose-response study. The patients were treated with either conventional radiotherapy or intensity-modulated radiotherapy. Dose-volume histograms for the parotid glands were derived from three-dimensional dose calculations using computed tomography scans. Stimulated salivary flow rates were measured before and 1 year after radiotherapy. A threshold of 25% of the pretreatment flow rate was used to define a complication. The evaluated models included the Lyman-Kutcher-Burman model, the mean dose model, the relative seriality model, the critical volume model, the parallel functional subunit model, and the dose-threshold model. The goodness of fit (GOF) was determined by the deviance and a Monte Carlo hypothesis test. Ranking of the models was based on Akaike's information criterion (AIC). Results: None of the models was rejected based on the evaluation of the GOF. The mean dose model was ranked as the best model based on the AIC. The TD{sub 50} in these models was approximately 39 Gy. Conclusions: The mean dose model was preferred for describing the dose-response relationship of the parotid gland.

• OSTI ID: 21372188
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 4 Vol. 76; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BODY
CALCULATION METHODS
COMPUTERIZED TOMOGRAPHY
DIAGNOSTIC TECHNIQUES
DISEASES
DOSE-RESPONSE RELATIONSHIPS
GLANDS
HEAD
MEDICINE
MONTE CARLO METHOD
NECK
NEOPLASMS
NUCLEAR MEDICINE
ORGANS
RADIOLOGY
RADIOTHERAPY
SALIVARY GLANDS
THERAPY
TOMOGRAPHY