title: Treatment planning systems dosimetry auditing project in Portugal.
abstract: OBJECTIVE
  The Medical Physics Division of the Portuguese Physics Society (DFM_SPF) in collaboration with the IAEA, carried out a national auditing project in radiotherapy, between September 2011 and April 2012. The objective of this audit was to ensure the optimal usage of treatment planning systems. The national results are presented in this paper.
  
  
  METHODS
  The audit methodology simulated all steps of external beam radiotherapy workflow, from image acquisition to treatment planning and dose delivery. A thorax CIRS phantom lend by IAEA was used in 8 planning test-cases for photon beams corresponding to 15 measuring points (33 point dose results, including individual fields in multi-field test cases and 5 sum results) in different phantom materials covering a set of typical clinical delivery techniques in 3D Conformal Radiotherapy.
  
  
  RESULTS
  All 24 radiotherapy centers in Portugal have participated. 50 photon beams with energies 4-18 MV have been audited using 25 linear accelerators and 32 calculation algorithms. In general a very good consistency was observed for the same type of algorithm in all centres and for each beam quality.
  
  
  CONCLUSIONS
  The overall results confirmed that the national status of TPS calculations and dose delivery for 3D conformal radiotherapy is generally acceptable with no major causes for concern. This project contributed to the strengthening of the cooperation between the centres and professionals, paving the way to further national collaborations.
authors.affiliation: Serviço de Física Médica, IPOCFG, E.P.E., Av. Bissaya Barreto, 3000-075 Coimbra, Portugal. Electronic address: mclopes@ipocoimbra.min-saude.pt.
authors.forename: M C
authors.initials: MC
authors.lastname: Lopes
authors.affiliation: CHUC, Coimbra, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Cavaco
authors.affiliation: Hospital CUF Descobertas, Lisboa, Portugal.
authors.forename: K
authors.initials: K
authors.lastname: Jacob
authors.affiliation: Hospital de Santa Maria, CHLN, E.P.E., Lisboa, Portugal.
authors.forename: L
authors.initials: L
authors.lastname: Madureira
authors.affiliation: IRIO, Lisboa, Portugal.
authors.forename: S
authors.initials: S
authors.lastname: Germano
authors.affiliation: Hospital da Luz, Lisboa, Portugal.
authors.forename: S
authors.initials: S
authors.lastname: Faustino
authors.affiliation: IPOPFG, E.P.E., Porto, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Lencart
authors.affiliation: CHTMAD, E.P.E., Vila Real, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Trindade
authors.affiliation: CRP, Porto, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Vale
authors.affiliation: Centro Hospitalar S. Joao, E.P.E., Porto, Portugal.
authors.forename: V
authors.initials: V
authors.lastname: Batel
authors.affiliation: Clinica Quadrantes, Porto, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Sousa
authors.affiliation: Centro Oncologico Dra. Natalia Chaves, Carnaxide, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Bernardo
authors.affiliation: Unidade Radioterapia do Algarve (Quadrantes_Faro), Faro, Portugal.
authors.forename: S
authors.initials: S
authors.lastname: Brás
authors.affiliation: CLISA, Amadora, Portugal.
authors.forename: S
authors.initials: S
authors.lastname: Macedo
authors.affiliation: Hospital de Braga, Braga, Portugal.
authors.forename: D
authors.initials: D
authors.lastname: Pimparel
authors.affiliation: Dep. de Radioterapia e Oncologia Clinica, Porto, Portugal.
authors.forename: F
authors.initials: F
authors.lastname: Ponte
authors.affiliation: Clinica Quadrantes, Unidade Radioterapia do Funchal, Funchal, Portugal.
authors.forename: E
authors.initials: E
authors.lastname: Diaz
authors.affiliation: Lenicare/Hospital do Espírito Santo, Évora, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Martins
authors.affiliation: CHBM, E.P.E., Barreiro, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Pinheiro
authors.affiliation: Hospital de Santiago, Setúbal, Portugal.
authors.forename: F
authors.initials: F
authors.lastname: Marques
authors.affiliation: Quadrantes Santarém, Hospital de Santarém, Santarém, Portugal.
authors.forename: C
authors.initials: C
authors.lastname: Batista
authors.affiliation: Centro Clinico do SAMS, Lisboa, Portugal.
authors.forename: L
authors.initials: L
authors.lastname: Silva
authors.affiliation: Fundação Champalimaud, Lisboa, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Rodrigues
authors.affiliation: IPOLFG, E.P.E., Lisboa, Portugal.
authors.forename: L
authors.initials: L
authors.lastname: Carita
authors.affiliation: North Estonia Regional Hospital, Tallinn, Estonia.
authors.forename: E
authors.initials: E
authors.lastname: Gershkevitsh
authors.affiliation: International Atomic Energy Agency, Vienna, Austria.
authors.forename: J
authors.initials: J
authors.lastname: Izewska
mesh_terms: D054869:Clinical Audit; D019047:Phantoms, Imaging; D011174:Portugal; D011874:Radiometry / Q000592:standards*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000592:standards*
keywords: Dose calculation algorithms; Dosimetry audit; Treatment planning systems