title: Dose painting by numbers based on retrospectively determined recurrence probabilities.
abstract: The aim of this study is to derive "dose painting by numbers" prescriptions from retrospectively observed recurrence volumes in a patient group treated with conventional radiotherapy for head and neck squamous cell carcinoma.
  
  
  
  The spatial relation between retrospectively observed recurrence volumes and pre-treatment standardized uptake values (SUV) from fluorodeoxyglucose positron emission tomography (FDG-PET) imaging was determined. Based on this information we derived SUV driven dose-response functions and used these to optimize ideal dose redistributions under the constraint of equal average dose to the tumor volumes as for a conventional treatment. The response functions were also implemented into a treatment planning system for realistic dose optimization.
  
  
  
  The calculated tumor control probabilities (TCP) increased between 0.1-14.6% by the ideal dose redistributions for all included patients, where patients with larger and more heterogeneous tumors got greater increases than smaller and more homogeneous tumors.
  
  
  
  Dose painting prescriptions can be derived from retrospectively observed recurrence volumes spatial relation to pre-treatment FDG-PET image data. The ideal dose redistributions could significantly increase the TCP for patients with large tumor volumes and large spread in SUV from FDG-PET. The results yield a basis for prospective studies to determine the clinical value for dose painting of head and neck squamous cell carcinomas.
authors.affiliation: Medical Radiation Sciences, Department of Immunology, Genetics and Pathology, Uppsala University, Sweden. Electronic address: eric.gronlund@igp.uu.se.
authors.forename: Eric
authors.initials: E
authors.lastname: Grönlund
authors.affiliation: Experimental and Clinical Oncology, Department of Immunology, Genetics and Pathology, Uppsala University, Sweden; Uppsala University Hospital, Sweden.
authors.forename: Silvia
authors.initials: S
authors.lastname: Johansson
authors.affiliation: Medical Radiation Sciences, Department of Immunology, Genetics and Pathology, Uppsala University, Sweden; Uppsala University Hospital, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Montelius
authors.affiliation: Medical Radiation Sciences, Department of Immunology, Genetics and Pathology, Uppsala University, Sweden; Uppsala University Hospital, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Ahnesjö
mesh_terms: D000328:Adult; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D049268:Positron-Emission Tomography; D011336:Probability; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D000077195:Squamous Cell Carcinoma of Head and Neck; D014057:Tomography, X-Ray Computed / Q000379:methods; D047368:Tumor Burden
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: Dose painting; Dose painting by numbers; Dose painting optimization; FDG-PET/CT; Head and neck cancer