title: Contouring of the Pharyngeal Superior Constrictor Muscle (PSCM). A cooperative study of the Italian Association of Radiation Oncology (AIRO) Head and Neck Group.
abstract: OBJECTIVE
  Irradiation of the Pharyngeal Superior Constrictor Muscle (PSCM) seems to play a crucial role in radiation-related swallowing dysfunctions. Purpose of our study was to quantify operator-related variability in the contouring of PSCM on Computed Tomography (CT) scans and adherence with contours derived from MR images.
  
  
  METHODS
  Three sets of treatment planning CT and their corresponding MR images were selected. Contouring of the PSCM was performed using both a literature-based method, derived from literature review, and an optimized method, derived from Magnetic Resonance (MR) images thus obtaining "literature-based" and "optimized" contours. Each operator contoured the PSCM on CT scans according to both methods for three times in three different days. Inter- and intra-operator variability and adherence to a contour obtained from MR images (named "MR-derived" contour) were analyzed.
  
  
  RESULTS
  Thirty-four operators participated and 612 contours were obtained. Both intra- and inter-operator variability and adherence to the "MR-derived" contour were significantly different between the two methods (p⩽0.05). The "optimized" method showed a lower intra- and inter-operator variability and a higher adherence to the "MR-derived" contour.
  
  
  CONCLUSIONS
  The "optimized" method ameliorates both operator-related variability and adherence with MR images.
authors.affiliation: Advanced Radiotherapy Center, European Institute of Oncology, Milan, Italy. Electronic address: daniela.alterio@ieo.it.
authors.forename: Daniela
authors.initials: D
authors.lastname: Alterio
authors.affiliation: Advanced Radiotherapy Center, European Institute of Oncology, Milan, Italy.
authors.forename: Delia
authors.initials: D
authors.lastname: Ciardo
authors.affiliation: Division of Radiology, Istituto Europeo di Oncologia, Milano, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Preda
authors.affiliation: Istituto Nazionale per lo studio e la cura dei tumori, Fondazione G.Pascale IRCCS Napoli, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Argenone
authors.affiliation: Ospedale Fatebenefratelli Isola Tiberina, Roma, Italy.
authors.forename: Orietta
authors.initials: O
authors.lastname: Caspiani
authors.affiliation: Ospedale S. Maria Nuova, Reggio Emilia, Italy.
authors.forename: Renato
authors.initials: R
authors.lastname: Micera
authors.affiliation: Azienda Ospedaliera - Universitaria "San Luigi Gonzaga" di Orbassano, Università di Torino, Italy.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Ruo Redda
authors.affiliation: Ospedale S. Croce e Carle, Cuneo, Italy.
authors.forename: Elvio G
authors.initials: EG
authors.lastname: Russi
authors.affiliation: Ospedale S. Anna, Como, Italy.
authors.forename: Ernestina
authors.initials: E
authors.lastname: Bianchi
authors.affiliation: Fondazione IRCSS Istituto Nazionale dei Tumori, Milano, Italy.
authors.forename: Ester
authors.initials: E
authors.lastname: Orlandi
authors.affiliation: IRCSS AOU San Martino IST, Genova, Italy.
authors.forename: Almalina
authors.initials: A
authors.lastname: Bacigalupo
authors.affiliation: Ospedale dell'Angelo, Mestre, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Busetto
authors.affiliation: Ospedale di Ivrea, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Cante
authors.affiliation: S.C. Radioterapia AOU Maggiore della Carità, Università degli Studi del Piemonte Orientale, Novara, Italy.
authors.forename: Letizia
authors.initials: L
authors.lastname: Deantonio
authors.affiliation: Dipartimento di scienze medico-chirurgiche e medicina traslazionale, "Sapienza" Università di Roma, Università La Sapienza, Italy.
authors.forename: Vitaliana
authors.initials: V
authors.lastname: De Sanctis
authors.affiliation: Radiation Oncology Department - TomoTherapy Unit, AUSL Valle d'Aosta, Aosta, Italy.
authors.forename: Pierfrancesco
authors.initials: P
authors.lastname: Franco
authors.affiliation: U.O.C. Radioterapia, Ospedale S. Donato Arezzo, Italy.
authors.forename: Luciana
authors.initials: L
authors.lastname: Lastrucci
authors.affiliation: Istituto Nazionale Tumori Regina Elena, Roma, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Marucci
authors.affiliation: Azienda Ospedaliera di Busto Arsizio, Varese, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Merlotti
authors.affiliation: Ospedale di Circolo, Varese, Italy.
authors.forename: Marinella
authors.initials: M
authors.lastname: Molteni
authors.affiliation: Azienda Ospedaliera Universitaria Careggi, Università di Firenze, Italy.
authors.forename: Fabiola
authors.initials: F
authors.lastname: Pajar
authors.affiliation: Ospedale S. Giovanni Battista, Università di Torino, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Rampino
authors.affiliation: Division of Epidemiology and Biostatistics, Istituto Europeo di Oncologia, Milano, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Santoro
authors.affiliation: Advanced Radiotherapy Center, European Institute of Oncology, Milan, Italy.
authors.forename: Annamaria
authors.initials: A
authors.lastname: Ferrari
authors.affiliation: Advanced Radiotherapy Center, European Institute of Oncology, Milan, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Bazzani
authors.affiliation: Advanced Radiotherapy Center, European Institute of Oncology, Milan, Italy.
authors.forename: Mariangela
authors.initials: M
authors.lastname: Caputo
authors.affiliation: Ospedale S. Anna, Como, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Laudati
authors.affiliation: Istituto Nazionale per lo studio e la cura dei tumori, Fondazione G.Pascale IRCCS Napoli, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Borzillo
authors.affiliation: Seconda Università degli Studi di Napoli, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Falivene
authors.affiliation: Ospedale S. Maria Nuova, Reggio Emilia, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Simoni
authors.affiliation: Ospedale S. Maria Nuova, Reggio Emilia, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Vigo
authors.affiliation: Fondazione IRCSS Istituto Nazionale dei Tumori, Milano, Italy.
authors.forename: Eva
authors.initials: E
authors.lastname: Iannacone
authors.affiliation: Ospedale S. Croce e Carle, Cuneo, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Reali
authors.affiliation: Ospedale Fatebenefratelli Isola Tiberina, Roma, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Bonanni
authors.affiliation: Ospedale Fatebenefratelli Isola Tiberina, Roma, Italy.
authors.forename: Mariavittoria
authors.initials: M
authors.lastname: Leone
authors.affiliation: Ospedale S. Croce e Carle, Cuneo, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Giannello
authors.affiliation: Ospedale S. Croce e Carle, Cuneo, Italy.
authors.forename: Riccardo Vigna
authors.initials: RV
authors.lastname: Taglianti
authors.affiliation: Advanced Radiotherapy Center, European Institute of Oncology, Milan, Italy; Università di Milano, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Orecchia
mesh_terms: D000704:Analysis of Variance; D006801:Humans; D007558:Italy; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015588:Observer Variation; D010609:Pharyngeal Muscles / Q000033:anatomy & histology*; D017410:Practice Guidelines as Topic; D011446:Prospective Studies; D018787:Radiation Oncology / Q000379:methods*; D015203:Reproducibility of Results; D012955:Societies, Medical; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Dysphagia; Head and neck cancer; IMRT; Pharyngeal constrictor muscles; Toxicity