title: High-LET radiotherapy for adenoid cystic carcinoma of the head and neck: 15 years' experience with raster-scanned carbon ion therapy.
abstract: OBJECTIVE
  Locoregional control (LC) in malignant salivary gland tumors is dose-dependent, initial results with particle therapy were promising. We report our experience with raster-scanned, intensity-controlled carbon ion therapy (C12) and IMRT in 309 patients with pathologically confirmed adenoid cystic carcinoma (ACC) of the head and neck.
  
  
  METHODS
  Treatment records of patients treated with C12 between 08/1998 and 05/2013 were evaluated regarding tumor stage, treatment, toxicity (CTCAE v3), LC, progression-free survival (PFS) and overall survival (OS). Response assessment was carried out according to RECIST1.1.
  
  
  RESULTS
  Tumor stages were mostly advanced (T4a/b: 60%, macroscopic disease: 71%), most common sites of origin were the paranasal sinus (37%). At a median follow-up at 33.9 months, LC, PFS, and OS at 3 and 5 year estimates are 83.7%/58.5%, 67.8%/56.1%, and 88.9%/74.6%. LC correlates with T-stage but neither nodal stage, age, relapse state, nor margin status. RECIST did not correlate with LC or survival rates.
  
  
  CONCLUSIONS
  IMRT plus C12 boost results in good control and survival rates at moderate toxicity. Margin status did not correlate with LC in T4 tumors, extensive and potentially mutilating surgical procedures may have to be re-evaluated. RECIST assessment did not correlate with either LC or survival rates; potentially more meaningful radiological parameters need to be developed.
authors.affiliation: Dept of Radiation Oncology, University of Heidelberg, Germany. Electronic address: alexdjensen@gmx.de.
authors.forename: Alexandra D
authors.initials: AD
authors.lastname: Jensen
authors.affiliation: Dept of Radiation Oncology, University of Heidelberg, Germany. Electronic address: Melaniepoulakis@aol.com.
authors.forename: Melanie
authors.initials: M
authors.lastname: Poulakis
authors.affiliation: Dept of Radiation Oncology, University of Heidelberg, Germany. Electronic address: Anna.nikoghosyan@helios-kliniken.de.
authors.forename: Anna V
authors.initials: AV
authors.lastname: Nikoghosyan
authors.affiliation: Dept of Radiation Oncology, University of Heidelberg, Germany. Electronic address: thomas.welzel@med.uni-heidelberg.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Welzel
authors.affiliation: Dept of Radiation Oncology, University of Heidelberg, Germany. Electronic address: matthias.uhl@med.uni-heidelberg.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Uhl
authors.affiliation: Dept of Otorhinolaryngology, University of Heidelberg, Germany. Electronic address: philippe.federspil@med.uni-heidelberg.de.
authors.forename: Philippe A
authors.initials: PA
authors.lastname: Federspil
authors.affiliation: Dept of Dental and Oro-maxillofacial Surgery, University of Heidelberg, Germany. Electronic address: kolja.freier@med.uni-heidelberg.de.
authors.forename: Kolja
authors.initials: K
authors.lastname: Freier
authors.affiliation: Dept of Medical Oncology, National Center for Tumor Disease (NCT), Heidelberg, Germany. Electronic address: juergen.krauss@med.uni-heidelberg.de.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Krauss
authors.affiliation: Medical Informatics and Regulatory Affairs, Heidelberg Ion Beam Therapy Centre, Germany. Electronic address: angelika.hoess@med.uni-heidelberg.de.
authors.forename: Angelika
authors.initials: A
authors.lastname: Höss
authors.affiliation: Heidelberg Ion Beam Therapy Centre, Germany. Electronic address: Thomas.haberer@med.uni-heidelberg.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Haberer
authors.affiliation: Heidelberg Ion Beam Therapy Centre, Germany. Electronic address: Oliver.jaekel@med.uni-heidelberg.de.
authors.forename: Oliver
authors.initials: O
authors.lastname: Jäkel
authors.affiliation: Dept of Radiation Oncology, University of Heidelberg, Germany. Electronic address: m.muenter@klinikum-stuttgart.de.
authors.forename: Marc W
authors.initials: MW
authors.lastname: Münter
authors.affiliation: Dept of Radiation Oncology, University of Heidelberg, Germany. Electronic address: daniela.ertner@fdk.info.
authors.forename: Daniela
authors.initials: D
authors.lastname: Schulz-Ertner
authors.affiliation: Molecular Radiation Oncology (E055), German Cancer Research Centre (DKFZ), Heidelberg, Germany. Electronic address: p.huber@dkfz-heidelberg.de.
authors.forename: Peter E
authors.initials: PE
authors.lastname: Huber
authors.affiliation: Dept of Radiation Oncology, University of Heidelberg, Germany. Electronic address: juergen.debus@med.uni-heidelberg.de.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Debus
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003528:Carcinoma, Adenoid Cystic / Q000532:radiotherapy*; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D063193:Heavy Ion Radiotherapy / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012468:Salivary Gland Neoplasms / Q000532:radiotherapy*; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult
keywords: ACC; Adenoid cystic carcinoma; Carbon ion therapy; Carbon ions; IMRT; MSGTs; Malignant salivary gland tumors; Raster-scanning