Oleg N Vassiliev, Ph.D.
Department of Radiation Physics, Division of Radiation Oncology
Present Title & Affiliation
Primary Appointment
Associate Professor, Department of Radiation Physics - Research, Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
Education & Training
Degree-Granting Education
2001 | The University of Western Ontario, London, Ontario, CAN, PHD, Theoretical Physics |
1989 | Tomsk Polytechnic Institute, Russia, RUS, PHD, Nuclear physics and physics of elementary particles |
Board Certifications
2009 | American Board of Radiology |
Honors & Awards
2014 | Featured article, Physics in Medicine and Biology |
2014 | Editor's choice paper, medicalphysicsweb.org |
2013 | Best 25 referees, Physics in Medicine and Biology |
2012 | Best 20 referees, Physics in Medicine and Biology |
2011 | Best 20 referees, Physics in Medicine and Biology |
2010 | Highlights of the year, paper 1, Physics in Medicine and Biology |
2010 | Editor's choice paper, medicalphysicsweb.org |
2010 | Highlights of the year, paper 2, Physics in Medicine and Biology |
2009 | Highlights of the year paper, Physics in Medicine and Biology |
2008 | Highlights of the year paper, Physics in Medicine and Biology |
2000 | Ontario Graduate Scholarship, The Government of Ontario |
1999 | Ontario Graduate Scholarship in Science and Technology, The Government of Ontario |
1998 | L. Margaret and W. D. Jackson Scholarship, The University of Western Ontario |
Selected Publications
Peer-Reviewed Articles
- Vassiliev ON, Peterson CB, Chang JY, Mohan R. Monte Carlo evaluation of target dose coverage in lung stereotactic body radiation therapy with flattening filter-free beams. J Radiother Pract 21(1):1-7, 2022. e-Pub 2020. PMID: 35401050.
- Vassiliev ON, Peterson CB, Chang JY, Mohan R. Using FFF beams to improve the therapeutic ratio of lung SBRT. J Radiother Pract 20(4):1-7, 2021. e-Pub 2020. PMID: 35330584.
- Chetvertkov MA, Vassiliev ON, Yang J, Wang HC, Liu AY, Liao Z, Mohan R. Impact of Intra-Fractional Motion on Dose Distributions in Lung IMRT. J Radiother Pract 20(1):12-16, 2021. e-Pub 2020. PMID: 34168519.
- Vassiliev ON, Peterson CB, Grosshans DR, Mohan R. A simple model for calculating relative biological effectiveness of X-rays and gamma radiation in cell survival. Br J Radiol 93(1112):20190949, 2020. e-Pub 2020. PMID: 32464080.
- Kry SF, Feygelman V, Balter P, Knöös T, Charlie Ma CM, Snyder M, Tonner B, Vassiliev ON. AAPM Task Group 329: Reference dose specification for dose calculations: dose-to-water or dose-to-muscle?. Med Phys 47(3):e52-e64, 2020. e-Pub 2020. PMID: 31883390.
- Vassiliev ON, Peterson CB, Cao W, Grosshans DR, Mohan R. Systematic microdosimetric data for protons of therapeutic energies calculated with Geant4-DNA. Phys Med Biol 64(21):215018, 2019. e-Pub 2019. PMID: 31553958.
- Vassiliev ON, Kry SF, Wang HC, Peterson CB, Chang JY, Mohan R. Radiotherapy of lung cancers: FFF beams improve dose coverage at tumor periphery compromised by electronic disequilibrium. Phys Med Biol 63(19):195007, 2018. e-Pub 2018. PMID: 30189421.
- Vassiliev ON, Kry SF, Grosshans DR, Mohan R. Average Stopping Powers For Electron And Photon Sources For Radiobiological Modeling and Microdosimetric Applications. Phys Med Biol 63(5):055007, 2018. e-Pub 2018. PMID: 29411712.
- Vassiliev ON, Grosshans DR, Mohan R. A new formalism for modelling parameters α and β of the linear quadratic model of cell survival for hadron therapy. Phys Med Biol 62(20):8041-8059, 2017. e-Pub 2017. PMID: 28832343.
- Wang H, Vassiliev ON. Radial dose distributions from carbon ions of therapeutic energies calculated with Geant4-DNA. Phys Med Biol 62(10):N219-N227, 2017. e-Pub 2017. PMID: 28362271.
- Vassiliev ON. Uncertainties in the relative biological effectiveness of therapeutic proton beams associated with bias towards high doses per fraction in radiobiological experiments. Int J Cancer Therapy Oncol 4(4):446, 2016.
- Newhauser WD, Zhang R, Jones TG, Giebeler A, Taddei PJ, Stewart RD, Lee A, Vassiliev O. Reducing the cost of proton radiation therapy: the feasibility of a streamlined treatment technique for prostate cancer. Cancers (Basel) 7(2):688-705, 2015. e-Pub 2015. PMID: 25920039.
- St Aubin J, Keyvanloo A, Vassiliev ON, Fallone BG. Inclusion of magnetic field effects in a deterministic solution to the first order linear Boltzmann transport equation. Med Phys 47:780-793, 2015.
- Wang H, Vassiliev ON. Radial dose distributions from protons of therapeutic energies calculated with Geant4-DNA. Phys Med Biol 59(14):3657-68, 2014. e-Pub 2014. PMID: 24925886.
- Wang H, Vassiliev ON. Microdosimetric characterization of radiation fields for modelling tissue response in radiotherapy. Int J Cancer Ther Oncol 2(1):020116, 2014.
- Vassiliev ON. A model of the radiation-induced bystander effect based on an analogy with ferromagnets. Application to modelling tissue response in a uniform field. Physica A 416:242-251, 2014.
- Wang X, Yang JN, Li X, Tailor R, Vassiliev O, Brown P, Rhines L, Chang E. Effect of spine hardware on small spinal stereotactic radiosurgery dosimetry. Phys Med Biol 58:6733-6747, 2013.
- Vassiliev ON, Kudchadker RJ, Kuban DA, Frank SJ, Choi S, Nguyen Q, Lee AK. Dosimetric impact of fiducial markers in patients undergoing photon beam radiation therapy. Phys Med 28(3):240-4, 2012. e-Pub 2011. PMID: 21875820.
- Vassiliev ON. Formulation of the multi-hit model with a non-Poisson distribution of hits. Int J Radiat Oncol Biol Phys 83(4):1311-6, 2012. e-Pub 2012. PMID: 22245202.
- Vassiliev ON. Electron slowing-down spectra in water for electron and photon sources calculated with the Geant4-DNA code. Phys Med Biol 57(4):1087-94, 2012. e-Pub 2012. PMID: 22297165.
- Vassiliev ON, Kudchadker RJ, Swanson DA, Bruno TL, van Vulpen M, Frank SJ. Displacement of periurethral stranded seeds and its dosimetric consequences in prostate brachytherapy. Brachytherapy 10(5):401-8, 2011. e-Pub 2011. PMID: 21306959.
- Kry SF, Vassiliev ON, Mohan R. Out-of-field photon dose following removal of the flattening filter from a medical accelerator. Phys Med Biol 55(8):2155-2166, 2010. e-Pub 2010. PMID: 20305334.
- Vassiliev ON, Wareing TA, McGhee J, Failla G, Salehpour MR, Mourtada F. Validation of a new grid based Boltzmann equation solver for dose calculation in radiotherapy with photon beams. Phys Med Biol 55(3):581-598, 2010. e-Pub 2010. PMID: 20057008.
- Kry SF, Howell RM, Polf J, Mohan R, Vassiliev ON. Treatment vault shielding for a flattening filter-free medical linear accelerator. Phys Med Biol 54(5):1265-1273, 2009. e-Pub 2009. PMID: 19190359.
- Vassiliev ON, Kry SF, Chang JY, Balter PA, Titt U, Mohan R. Stereotactic radiotherapy for lung cancer using a flattening filter free Clinac. J Appl Clin Med Phys 10(1):14-21, 2009. e-Pub 2009. PMID: 19223837.
- Vassiliev ON, Wareing TA, Davis IM, McGhee J, Barnett D, Horton JL, Gifford K, Failla G, Titt U, Mourtada F. Feasibility of a multigroup deterministic solution method for three-dimensional radiotherapy dose calculations. Int J Radiat Oncol Biol Phys 72(1):220-7, 2008. PMID: 18722273.
- Kry SF, Howell RM, Titt U, Salehpour M, Mohan R, Vassiliev ON. Energy spectra, sources, and shielding considerations for neutrons generated by a flattening filter-free Clinac. Med Phys 35(5):1906-1911, 2008. PMID: 18561666.
- Titt U, Zheng Y, Vassiliev ON, Newhauser WD. Monte Carlo investigation of collimator scatter of proton-therapy beams produced using the passive scattering method. Phys Med Biol 53(2):487-504, 2008. e-Pub 2007. PMID: 18185001.
- Kry SF, Titt U, Followill D, Poenisch F, Vassiliev ON, White RA, Stovall M, Salehpour M. A Monte Carlo model for out-of-field dose calculation from high-energy photon therapy. Med Phys 34(9):3489-99, 2007. PMID: 17926952.
- Vassiliev ON, Kry SF, Kuban DA, Salehpour M, Mohan R, Titt U. Treatment planning study of prostate cancer intensity-modulated radiotherapy with a Varian Clinac operated without a flattening filter. Int J Radiat Oncol Biol Phys 68(5):1567-1571, 2007. e-Pub 2007. PMID: 17544596.
- Kry SF, Titt U, Poenisch F, Vassiliev ON, Salehpour M, Gillin M, Mohan R. Reduced neutron production through use of a flattening-filter-free accelerator. Int J Radiat Oncol Biol Phys 68(4):1260-1264, 2007. PMID: 17637397.
- Cho SH, Vassiliev ON, Horton JL. Comparison between an event-by-event Monte Carlo code, NOREC, and ETRAN for electron scaled point kernels between 20 keV and 1 MeV. Radiat Environ Biophys 46(1):77-83, 2007. e-Pub 2007. PMID: 17219152.
- Vassiliev ON, Titt U, Kry SF, Mohan R, Gillin MT. Radiation safety survey on a flattening filter free medical accelerator. Radiat Prot Dosimetry 124(2):187-190, 2007. e-Pub 2007. PMID: 17681966.
- Jang SY, Liu HH, Wang X, Vassiliev ON, Siebers JV, Dong L, Mohan R. Dosimetric verification for intensity-modulated radiotherapy of thoracic cancers using experimental and Monte Carlo approaches. Int J Radiat Oncol Biol Phys 66(3):939-948, 2006. PMID: 17011466.
- Kry SF, Titt U, Poenisch F, Followill D, Vassiliev ON, White RA, Mohan R, Salehpour M. A Monte Carlo model for calculating out-of-field dose from a varian 6 MV beam. Med Phys 33(11):4405-13, 2006. PMID: 17153419.
- Titt U, Vassiliev ON, Poenisch F, Kry SF, Mohan R. Monte Carlo study of backscatter in a flattening filter free clinical accelerator. Med Phys 33(9):3270-3273, 2006. PMID: 17022221.
- Poenisch F, Titt U, Vassiliev ON, Kry SF, Mohan R. Properties of unflattened photon beams shaped by a multileaf collimator. Med Phys 33(6):1738-1746, 2006. PMID: 16872081.
- Titt U, Vassiliev ON, Poenisch F, Dong L, Liu H, Mohan R. A Flattening Filter Free Photon Treatment Concept Evaluation with Monte Carlo. Med Phys 33(6):1595-1602, 2006. PMID: 16872067.
- Vassiliev ON, Titt U, Kry SF, Poenisch F, Gillin MT, Mohan R. Monte Carlo study of photon fields from a flattening filter-free clinical accelerator. Med Phys 33(4):820-827, 2006. PMID: 16696457.
- Vassiliev ON, Titt U, Poenisch F, Kry SF, Mohan R, Gillin MT. Dosimetric Properties of Photon Beams from a Flattening Filter Free Clinical Accelerator. Phys Med Biol 51(7):1907-1917, 2006. e-Pub 2006. PMID: 16552113.
- Jang SY, Vassiliev ON, Liu HH, Mohan R, Siebers JV. Development and commissioning of a multileaf collimator model in monte carlo dose calculations for intensity-modulated radiation therapy. Med Phys 33(3):770-81, 2006. PMID: 16878579.
- Poenisch F, Titt U, Kry SF, Vassiliev ON, Mohan R. MCNPX Simulation of a Multi Leaf Collimator. Med Phys 33(2):402-404, 2006. PMID: 16532947.
- Matsen MW, Griffiths GH, Wickham RA, Vassiliev ON. Monte Carlo phase diagram for diblock copolymer melts. J Chem Phys 124(2):024904, 2006. PMID: 16422645.
- Beddar AS, Briere TM, Mourtada FA, Vassiliev ON, Liu HH, Mohan R. Monte Carlo calculations of the absorbed dose and energy dependence of plastic scintillators. Med Phys 32(5):1265-1269, 2005. PMID: 15984678.
- Cho SH, Vassiliev ON, Lee S, Liu HH, Ibbott GS, Mohan R. Reference photon dosimetry data and reference phase space data for the 6 MV photon beam from varian clinac 2100 series linear accelerators. Med Phys 32(1):137-48, 2005. PMID: 15719964.
- Vassiliev ON, Matsen M. Fluctuation effects in block copolymer melts. J Chem Phys 118:7700-7713, 2003.
- Vassiliev ON, Cottam M, Rojdestvenski I. Quantum Monte-Carlo study of phase transitions in Heisenberg chains with long-range interactions. J Magn Magn Mater 226:558-559, 2001.
- Vassiliev ON, Rojdestvenski I, Cottam M. Quantum Monte-Carlo study of the Heisenberg chain with long-range ferromagnetic interactions. Physica A 294:139-154, 2001.
- Vassiliev O, Cottam M, Rojdestvenski I. Quantum Monte-Carlo study of a Heisenberg spin system in two dimensions with long-range interactions. J Appl Phys 89:7329-7331, 2001.
- Argall PS, Vassiliev ON, Sica RJ, Mwangi MM. Lidar measurements taken with a large-aperture liquid mirror. 2. Sodium resonance-fluorescence system. Appl Opt 39(15):2393-400, 2000. PMID: 18345149.
- Vassiliev O, Cottam M. Optically nonlinear s-polarized electromagnetic waves in multilayered symmetric dielectrics. Surf Rev Lett 7:89-102, 2000.
- Vassiliev ON. The influence of short tracks on the biological effectiveness of radiations. Radiat Protect Dosim 62:179-182, 1995.
- Lappa A, Bigildeev E, Burmistrov D, Vassiliev ON. TRION code for radiation action calculations and its application in microdosimetry and radiobiology. Radiat Environ Biophys 70:48-55, 1991.
- Lappa A, Vassiliev ON,. Effects of radiation spectra on radiation effects yields, relative biological effectiveness and quality coefficients. Sov Atomic Energy 70:48-55, 1991.
- Lappa A, Burmistrov D, Vassiliev ON. Calculation of microdosimetric characteristics in electron and gamma-ray irradiated water. Sov Phys J 31:149-153, 1988.
- Lappa A, Burmistrov D, Vassiliev ON. Fluctuations of the energy absorption of electron-photon radiation in a model with collision-grouping elements. Sov Phys J 30:800-804, 1987.
- Kolchuzhkin A, Vassiliev ON. Using symmetry properties to modify estimates in calculations of radiation fields by the Monte Carlo method. Sov Atomic Energy 60:347-350, 1986.
Abstracts
- Vassiliev ON, Kry S, Peterson CB. A Model of the Relative Biological Effectiveness of X-Rays Based on a Survey of Experimental Data. Int J Radiat Oncol Biol Phys 102(3), 2018.
- Chetvertkov M, Vassiliev O, Yang J, Wang H, Liao Z, Mohan R. The Impact of Intra-Fractional Motion On Dose Distributions in Lung IMRT. Med Phys 45(6), 2018.
- Vassiliev O, Kry S, Wang H, Peterson C, Chang J, Mohan R. Radiotherapy of Lung Cancers: FFF Beams Enhance Dose to the GTV Surface and to Adjacent Regions of the CTV. Med Phys 45(6), 2018.
- Vassiliev ON, Mohan R, Grosshans DR. Derivation of LET-Dependence of LQ Model Beta Parameter From a Microdosimetric Cell Survival Model. Int J Radiat Oncol Biol Phys, 2017.
- Vassiliev O, Guan F, Bronk L, Grosshans D, Mohan R. SU-I-GPD-T-103: An LET-Based Model of Proton RBE Consistent with New High Accuracy RBE Data Measured Near Distal Fall-Off. Med Phys 44(6), 2017.
- Vassiliev O, Liao Z, Mohan R. SU-I-GPD-T-413: Accuracy Assurance of Computed Lung IMRT Dose Distributions for Treatment Response Analyses: Two Commercial Algorithms Vs Monte Carlo. Med Phys 44(6), 2017.
- Vassiliev O. SU-F-T-125: Radial Dose Distributions From Carbon Ions of Therapeutic Energies Calculated with Geant4-DNA. Med Phys 43(6):3490, 2016. PMID: 28046645.
- Vassiliev ON, Wang H. Microscopic Patterns of Radiation Damage in Tissue Generated With a Bystander Effect Model. Int J Radiat Oncol Biol Phys 93(35):S181, 2015.
Books (edited and written)
- Vassiliev O.N.. Monte Carlo Methods for Radiation Transport. Fundamentals and Advanced Topics. Springer International Publishing: Switzerland, 281, 2016.
Grant & Contract Support
Title: | Improving the Clinical Effectiveness and Understanding of the Biophysical Basis of Proton Therapy: Core B - Clinical & Research Support at MDACC |
Funding Source: | NIH/NCI |
Role: | Co-Investigator |
Title: | Improving dose coverage of tumor periphery in radiotherapy of lung cancer through the use of flattening filter free beams |
Funding Source: | NIH/NCI |
Role: | Principal Investigator |
Title: | Accounting for and harnessing RBE variability in proton therapy |
Funding Source: | NIH/NCI |
Role: | Principal Investigator |
Title: | Imaging and Radiation Oncology Core (IROC) Group Carbon Ion Therapy Supplement |
Funding Source: | American College of Radiology |
Role: | Co-Investigator |