Measurement and verification of positron emitter nuclei generated at each treatment site by target nuclear fragment reactions in proton therapy.

PURPOSE The purpose of this study is to verify the characteristics of the positron emitter nuclei generated at each treatment site by proton irradiation. METHODS Proton therapy using a beam on-line PET system mounted on a rotating gantry port (BOLPs-RGp), which the authors developed, is provided at the National Cancer Center Kashiwa, Japan. BOLPs-RGp is a monitoring system that can confirm the activity distribution of the proton irradiated volume by detection of a pair of annihilation gamma rays coincidentally from positron emitter nuclei generated by the target nuclear fragment reactions between irradiated proton nuclei and nuclei in the human body. Activity is measured from a start of proton irradiation to a period of 200 s after the end of the irradiation. The characteristics of the positron emitter nuclei generated in a patient's body were verified by the measurement of the activity distribution at each treatment site using BOLPs-RGp. RESULTS The decay curves for measured activity were able to be approximated using two or three half-life values regardless of the treatment site. The activity of half-life value of about 2 min was important for a confirmation of the proton irradiated volume. CONCLUSIONS In each proton treatment site, verification of the characteristics of the generated positron emitter nuclei was performed by using BOLPs-RGp. For the monitoring of the proton irradiated volume, the detection of (15)O generated in a human body was important.

[1]  Katia Parodi,et al.  Patient study of in vivo verification of beam delivery and range, using positron emission tomography and computed tomography imaging after proton therapy. , 2007, International journal of radiation oncology, biology, physics.

[2]  Mitsuyuki Abe,et al.  Usefulness of positron-emission tomographic images after proton therapy. , 2002, International journal of radiation oncology, biology, physics.

[3]  Katia Parodi,et al.  In-beam PET measurements of β+ radioactivity induced by proton beams , 2002 .

[4]  Koji Murakami,et al.  Distributions of beta+ decayed nuclei generated in the CH2 and H2O targets by the target nuclear fragment reaction using therapeutic MONO and SOBP proton beam. , 2005, Medical physics.

[5]  B. Emami,et al.  Tissue perfusion rate determined from the decay of oxygen-15 activity after photon activation in situ. , 1979, Science.

[6]  K. Parodi,et al.  Experimental study on the feasibility of in-beam PET for accurate monitoring of proton therapy , 2005, IEEE Transactions on Nuclear Science.

[7]  K Parodi,et al.  Potential application of PET in quality assurance of proton therapy. , 2000, Physics in medicine and biology.

[8]  Katia Parodi,et al.  In-beam PET measurements of biological half-lives of 12C irradiation induced β+-activity , 2008, Acta oncologica.

[9]  T Kanai,et al.  Washout measurement of radioisotope implanted by radioactive beams in the rabbit. , 2003, Physics in medicine and biology.

[10]  Wolfgang Enghardt,et al.  In-beam PET imaging for the control of heavy-ion tumour therapy , 1996 .

[11]  U Oelfke,et al.  Proton dose monitoring with PET: quantitative studies in Lucite. , 1996, Physics in medicine and biology.

[12]  K. Yoshida,et al.  Washout studies of 11C in rabbit thigh muscle implanted by secondary beams of HIMAC. , 2003, Physics in medicine and biology.

[13]  T. Yamashita,et al.  A compact planar positron imaging system , 2004 .

[14]  K Parodi,et al.  Dose quantification from in-beam positron emission tomography. , 2004, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[15]  Keiichi Nakagawa,et al.  Experimental verification of proton beam monitoring in a human body by use of activity image of positron-emitting nuclei generated by nuclear fragmentation reaction , 2008, Radiological physics and technology.

[16]  D W Litzenberg,et al.  On-line monitoring of radiotherapy beams: experimental results with proton beams. , 1999, Medical physics.

[17]  Katia Parodi,et al.  Charged hadron tumour therapy monitoring by means of PET , 2004 .

[18]  Keiichi Nakagawa,et al.  The development and clinical use of a beam ON-LINE PET system mounted on a rotating gantry port in proton therapy. , 2008, International journal of radiation oncology, biology, physics.

[19]  Hiroshi Uchida,et al.  Dose-volume delivery guided proton therapy using beam on-line PET system. , 2006, Medical physics.

[20]  James A. Scott.  Photon, Electron, Proton and Neutron Interaction Data for Body Tissues ICRU Report 46. International Commission on Radiation Units and Measurements, Bethesda, 1992, $40.00 , 1993 .

[21]  Katia Parodi,et al.  PET/CT imaging for treatment verification after proton therapy: a study with plastic phantoms and metallic implants. , 2007, Medical physics.

[22]  R. T. Ten Haken,et al.  Photon activation-15O decay studies of tumor blood flow. , 1981, Medical physics.