title: Principal component, Varimax rotation and cost analysis of volume effects in rectal bleeding in patients treated with 3D-CRT for prostate cancer.
abstract: We investigate the utility of principal component analysis as a tool for obtaining dose-volume combinations related to rectal bleeding after radiotherapy for prostate cancer. A direct implementation of principal component analysis reduces the number of degrees of freedom from the patient's dose-volume histograms that are associated with bleeding. However, when low-variance principal components are strongly correlated to outcome, their interpretation is problematic. A Varimax rotation is employed to aid in interpretability of the low-variance principal components. This procedure brings us closer to finding unique dose-volume combinations related to outcome but reintroduces correlation, requiring analysis of the overlap of information contained in such modes. Finally, we present examples of cost-benefit analyses for candidate dose-volume constraints for use in treatment planning.
authors.affiliation: Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Bauer
authors.forename: Andrew
authors.initials: A
authors.lastname: Jackson
authors.forename: Mark
authors.initials: M
authors.lastname: Skwarchuk
authors.forename: Michael
authors.initials: M
authors.lastname: Zelefsky
mesh_terms: D006471:Gastrointestinal Hemorrhage / Q000209:etiology* / Q000517:prevention & control*; D006801:Humans; D008297:Male; D025341:Principal Component Analysis; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000209:etiology / Q000517:prevention & control*; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000009:adverse effects*; D012007:Rectum / Q000528:radiation effects; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors