Oleg N Vassiliev, Ph.D.
Department of Radiation Physics, Division of Radiation Oncology Rsch Div.
Present Title & Affiliation
Primary Appointment
Associate Professor - Modified Service Appointment, Radiation Physics - Research, Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
Education & Training
Degree-Granting Education
| 2001 | The University of Western Ontario, London, Ontario, CA, Ph.D. in Theoretical Physics |
| 1989 | Tomsk Polytechnic Institute, Russia, RU, Ph.D. in Nuclear physics and physics of elementary particles |
Postgraduate Training
| 2003-2004 | Postdoctoral Fellowship, Physics, St. Francis Xavier University, Antigonish, Nova Scotia |
| 2002-2003 | Postdoctoral Fellowship, Medical physics, The University of Texas MD Anderson Cancer Center, Houston, Texas |
| 2001-2002 | Research Fellowship, Physics, The University of Reading, Reading |
Licenses & Certifications
| 2009 | American Board of Radiology |
| 2006 | Medical Physicist License awarded by the Texas Medical Board |
Experience & Service
Faculty Academic Appointments
Associate Professor, Radiation Physics - Research, Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, 2015 - 2025
Academic Medical Physicist, Mary Bird Perkins Cancer Center, Baton Rouge, LA, 2012 - 2015
Associate Professor, Louisiana State University, Baton Rouge, LA, 2012 - 2015
Academic Medical Physicist, Tom Baker Cancer Center, Calgary, 2010 - 2012
Assistant Professor, University of Calgary, Calgary, 2010 - 2012
Assistant Professor, Radiation Physics - Research, The University of Texas MD Anderson Cancer Center, Houston, TX, 2007 - 2010
Senior Research Scientist, Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, 2004 - 2006
Faculty, Theoretical Physics, Chelyabinsk State University, Chelyabinsk, 1989 - 1995
Honors & Awards
| 2014 | Featured article, Physics in Medicine and Biology |
| 2013 | Best 25 referees, Physics in Medicine and Biology |
| 2011 - 2012 | Best 20 referees, Physics in Medicine and Biology |
| 2010 | Editor's choice paper, medicalphysicsweb.org |
| 2010 | Highlights of the year, paper 1, Physics in Medicine and Biology |
| 2010 | Highlights of the year, paper 2, Physics in Medicine and Biology |
| 2008 - 2009 | 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 |
Professional Memberships
Selected Presentations & Talks
National Presentations
- Using FFF Beams Improves Tumor Control in Radiotherapy of Lung Cancer. Conference. AAPM. Anaheim, California, US.
- . Microscopic patterns of radiation damage in tissue generated with a bystander effect model. Conference. ASTRO. San Antonio, Texas, US.
- . Systematic microdosimetric data for protons calculated with Geant4-DNA. AAPM. San Antonio, Texas, US.
- Average LET of X-rays and gamma radiation for radiobiological modelling. PTCOG-NA. Miami, Florida, US.
Formal Peers
- 2002. Calculations of fluctuations in radiation fields. Invited. Harwell, GB.
- 2001. Quantum Monte Carol study of heisenberg ferromagnets. Invited. Waterloo, CA.
- 2001. Calculation of fluctuations in radiation fields. Invited. Hamilton, CA.
Grant & Contract Support
| Date: | 2024 - 2027 |
| Title: | Dose fractionation optimization for proton therapy, with and without immunotherapy, to maximize immune system stimulation to suppression ratio |
| Funding Source: | NIH/NCI |
| Role: | PI |
| Date: | 2024 - 2027 |
| Title: | Optimization of dose fractionation to enhance immuno-stimulating effect of proton beam therapy, with and without immunotherapy, to improve treatment outcomes |
| Funding Source: | Cancer Prevention & Research Institute of Texas (CPRIT) |
| Role: | PI |
| Date: | 2022 - 2025 |
| Title: | An innovative approach to improve the accuracy and consistency of hadrontherapy |
| Funding Source: | Cancer Prevention & Research Institute of Texas (CPRIT) |
| Role: | PI |
| Date: | 2021 - 2025 |
| Title: | Integrating patient-specific clinical and biological factors towards individualizing utilization of proton and photon radiation therapy. Project 3: Enhanced Sensitivity of Tumors to Proton Beam Therapy: Mechanisms and Biomarkers |
| Funding Source: | NIH/NCI |
| Role: | Investigator |
| ID: | 5P01CA261669-04 |
| Date: | 2021 - 2024 |
| Title: | An innovative approach to improve the accuracy and consistency of hadrontherapy |
| Funding Source: | NIH/NCI |
| Role: | PI |
| Date: | 2020 - 2025 |
| Title: | Advancing RBE models for high LET particles beyond the linear-quadratic model |
| Funding Source: | NIH/NCI |
| Role: | PI |
| ID: | R01CA256778 |
| Date: | 2018 - 2021 |
| Title: | Accounting for and harnessing RBE variability in proton therapy |
| Funding Source: | NIH/NCI |
| Role: | PI |
| ID: | 1 R01 CA225961-01 |
| Date: | 2018 - 2019 |
| Title: | Imaging and Radiation Oncology Core (IROC) Group Carbon Ion Therapy Supplement |
| Funding Source: | American College of Radiology |
| Role: | Co-I |
| ID: | CA180803 |
| Date: | 2017 - 2020 |
| 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: | PI |
| ID: | 1R03CA211143-01 |
| Date: | 2016 - 2017 |
| Title: | Improving target coverage in radiotherapy of spinal tumors through the use of FFF beams |
| Funding Source: | MDACC |
| Role: | PI |
| ID: | CROR – Radiation Physics and Technology Research Seed Grant |
| Date: | 2016 - 2017 |
| Title: | Linking the physical interactions and response to therapeutic protons at the DNA level |
| Funding Source: | MDACC |
| Role: | Co-I |
| ID: | CROR – Radiation Physics and Technology Research Seed Grant |
| Date: | 2014 - 2020 |
| 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-I |
| ID: | 5U19CA021239 |
| Date: | 2007 - 2010 |
| Title: | Deterministic radiotherapy dose calculation method |
| Funding Source: | NIH/NCI |
| Role: | Co-I |
| ID: | CA105806-02 |
| Date: | 2007 - 2009 |
| Title: | NO TITLE PROVIDED |
| Funding Source: | UT M.D. Anderson Cancer Center |
| Role: | Program Leader |
| Date: | 2004 - 2006 |
| Title: | Deterministic Radiotherapy Dose Calculation Method |
| Funding Source: | NIH/NCI |
| Role: | Co-I |
| ID: | CA105806-01 |
| Date: | 2004 - 2006 |
| Title: | Flattening Filter Free Linear Accelerator |
| Funding Source: | Varian Medical Systems |
| Role: | PI |
| ID: | Varian Master Research Agreement |
Selected Publications
Peer-Reviewed Articles
- Vassiliev, ON, Mohan, R. A novel microdosimetry-based formalism for cell survival modelling applicable to hypofractionated radiotherapy. Physics in medicine and biology 70(15), 2025. e-Pub 2025. PMID: 40675179.
- Vassiliev, ON. Accumulation of sublethal radiation damage and its effect on cell survival. Physics in medicine and biology 68(1), 2023. e-Pub 2023. PMID: 36533628.
- Vassiliev ON. Accumulation of sublethal radiation damage and its effect on cell survival. Phys. Med. Biol, 2022. e-Pub 2022.
- 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 2022. 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 2021. 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 2021. PMID: 34168519.
- Vassiliev ON. On calculation of the average linear energy transfer for radiobiological modelling. Biomed Phys Eng Express 7(1):015001, 2021. e-Pub 2021. PMID: 33692907.
- 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 2013.
- 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, 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 2012. PMID: 21875820.
- 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. e-Pub 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. e-Pub 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 2008. 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 2006. PMID: 16872067.
- 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.
- 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. e-Pub 2006. PMID: 16696457.
- 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 2005. PMID: 15719964.
- Vassiliev ON, Matsen M. Fluctuation effects in block copolymer melts. J Chem Phys 118:7700-7713, 2003. e-Pub 2003.
- 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. e-Pub 2001.
- 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. e-Pub 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. e-Pub 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. e-Pub 2000. PMID: 18345149.
- Vassiliev O, Cottam M. Optically nonlinear s-polarized electromagnetic waves in multilayered symmetric dielectrics. Surf Rev Lett 7:89-102, 2000. e-Pub 2000.
- Vassiliev ON. The influence of short tracks on the biological effectiveness of radiations. Radiat Protect Dosim 62:179-182, 1995. e-Pub 1995.
- 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. e-Pub 1991.
- 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 2017.
- Guan F, Bronk L, Kerr M, Ma D, Wang Y, Wang X, Li Y, Vassiliev O, Patel D, Titt U, Lin S, Grosshans D, Mohan R. TH-AB-605-8: Investigation of the Spatial Ionization Density Dependence of the DNA Damage in a Lung Cancer Cell Line with Proton Irradiations. Med Phys 44(6), 2017. e-Pub 2017.
- Bronk L, Guan F, Ma D, Wang Y, Kerr M, Patel D, Titt U, Vassiliev O, Lin S, Mohan R, Grosshans D. SU-K-108-8: High-Throughput Proton Irradiations Uncover a Differential DNA Damage Repair Response to P53 Depletion in Two Lung Cancer Cell Lines. Med Phys 44(6), 2017. e-Pub 2017.
- Newpower M, Vassiliev O, Guan F, Grosshans D, Bronk L, Mohan R. SU-K-108-2: A Novel Linear-Quadratic-Cubic Cell Survival Model for Proton Therapy Response Based On the Microdosimetric Quantity Specific Energy. Med Phys 44(6), 2017. e-Pub 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. e-Pub 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. e-Pub 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. e-Pub 2015.
- Vassiliev O, Wareing T, McGhee J, Failla G, Salehpour M, Mourtada F. Validation of a Grid-Based Boltzmann Solver for 6 and 18 MV Photon Beams Impinging On a Heterogeneous Phantom. Med Phys 36:2429-2429, 2009. e-Pub 2009.
- Vassiliev O, Kudchadker R, Kuban D, Lee A. Dosimetric Impact of Gold Fiducial Markers in Patients Undergoing External Beam Radiation Therapy. Med Phys 36:2491-2492, 2009. e-Pub 2009.
- Mikell J, Vassiliev O, Erwin W, Wareing T, Mourtada F. Comparing a Grid-Based Boltzmann Solver with Monte Carlo Simulation for Voxel-Based Therapeutic Radionuclide Dose Calculations. Med Phys 36:2772-2772, 2009. e-Pub 2009.
- Cho S, Krishnan S, Vassiliev O. On the clinical implementation of gold nanoparticle-aided radiation therapy (GNRT). Med Phys 35:2711, 2008. e-Pub 2008.
- Vassiliev O, Kudchadker R, Swanson D, Kuban D, Bruno T, Frank S. Systematic evaluation of periurethral stranded seed migration and its dosimetric consequences in prostate brachytherapy. Int J Radiat Oncol Biol Phys 72:S582, 2008. e-Pub 2008.
- Kry S, Howell R, Polf J, Mohan R, Vassiliev O. Vault shielding for a flattening filter-free Clinac. 11th International Conference on Radiation Shielding, 2008. e-Pub 2008.
- Vassiliev O, Mohan R. Elastic scattering of electrons in gold: an event-by-event simulation algorithm based On the NIST cross-section data. Med Phys 35:2697, 2008. e-Pub 2008.
- Kry S, Vassiliev O, Titt U, Mohan R. Dose outside the treatment volume following removal of the flattening filter. Med Phys 35:2983, 2008. e-Pub 2008.
- Titt U, Zheng Y, Vassiliev O, Newhauser W. Monte Carlo investigation of collimator scatter of proton-therapy beams produced using the passive scattering method. Med Phys 35:2797, 2008. e-Pub 2008.
- Vassiliev ON, Kry S, Chang J, Balter P, Titt U, Mohan R. Stereotactic radiotherapy for lung cancer using flattening filter free accelerator. Med Phys 34:2491-1, 2007. e-Pub 2007.
- Vassiliev O, Kry S, Mohan R, Titt U. Radiotherapy with a flattening filter free Clinac. Int J Radiat Oncol Biol Phys 69:S704, 2007. e-Pub 2007.
- Wareing T, Vassiliev ON, Failla G, Davis I, McGhee J, Barnett D, Horton J, Mourtata F. Validation of a prototype deterministic solver for photon beam dose calculations on acquired CT data in the presence of narrow beams and heterogeneities. Med Phys 34:2565, 2007. e-Pub 2007.
- Cho S, Vassiliev ON, Kuban D, Salehpour M, Gillin MT, Mohan R. Microscopic estimation of tumor dose enhancement during gold nanoparticle-aided radiation therapy (GNRT) using diagnostic energy range x-rays. Med Phys 34:2468-2469, 2007. e-Pub 2007.
- Vassiliev ON, Titt U, Mohan R. Low dose RBE of therapeutic photon beams. Med Phys 34:2467-7, 2007. e-Pub 2007.
- Poenisch F, Titt U, Vassiliev ON, Kry S, Zhu X, Mohan R. Properties of unflattened photon beams shaped by a multi leaf collimator. Med Phys 33:2131-1, 2006. e-Pub 2006.
- Kry S, Vassiliev ON, Kuban D, Salehpour M, Gillin MT, Mohan R. Prostate IMRT using inflattened beams. Int J of Radiat Onc Biol Phys 66:S78, 2006. e-Pub 2006.
- Kry S, Vassiliev ON, Kuban D, Poenisch F, Salehpour M, Gillin M, Mohan R. Treatment planning study of prostate cancer IMRT with a flattening filter free accelerator. Med Phys 32:2146-6, 2006. e-Pub 2006.
- Cho S, Vassiliev ON, Jang S, Krishnan S. Modifications of megavoltage photon beams for Gold Nanoparticle-Aided Radiation Therapy (GNRT) A Monte Carlo study. Med Phys 33:2121-1, 2006. e-Pub 2006.
- Titt U, Poenisch F, Kry S, Zhu X, Mohan R, Vassiliev ON. Monte Carlo simulation of backscatter in a flattening filter free clinac. Med Phys 33:2123-3, 2006. e-Pub 2006.
- Wareing T, Failla G, Vassiliev ON, Barnett A, McGhee J, Titt U, Horton J, Mourtada F. Performance assessment of a deterministic method incorporating coupled photon-electron transport for photon beam dose calculations on acquired CT data. Med Phys 33:2292-2293, 2006. e-Pub 2006.
- Vassiliev ON, Titt U, Gillin M, Mohan R. Dosimetric properties of 8 and 10 MV photon beams from a flattening filter free clinical accelerator. Med Phys 33:2292-2, 2006. e-Pub 2006.
- Vassiliev ON, Beddar A, Krishnan S, Briere T, Gillin M, Mohan R. A treatment planning study of liver cancer treatments with a flattening filter free linear accelerator. Med Phys 33:2064-4, 2006. e-Pub 2006.
- Jang S, Liu H, Vassiliev ON, Mohan R. Improving simulation efficiency of MLCs for Monte Carlo based dose calculation of IMRT. Med Phys 32:2012-2, 2005. e-Pub 2005.
- Kry S, Titt U, Poenisch F, Followill D, Vassiliev ON, Mohan R, Salehpour M. A Monte Carlo simulation of out-of-field radiation from an 18-MV beam. Med Phys 32:1889-9, 2005. e-Pub 2005.
- Kry S Titt U, Poenisch F, Vassiliev ON, Salehpour M, Gillin M, Mohan R. A reduction in neutron production through the use of a flattening-filter-free accelerator. Med Phys 32:2146-6, 2005. e-Pub 2005.
- Poenisch F, Titt U, Vassiliev ON, Kry S, Gillin M, Mohan R. The validation of a highly detailed multi leaf collimator model by comparing Monte Carlo simulations to measurements. Med Phys 32:2014-4, 2005. e-Pub 2005.
- Jang S, Liu H, Vassiliev ON, Mohan R. Impact of MLC modeling and sensitivity of its parameters on Monte Carlo simulation of IMRT. Med Phys 32:2017-7, 2005. e-Pub 2005.
- Cho S, Vassiliev ON, Horton J, Semenenko V. Benchmarking of an event-by-event Monte Carlo code, NORECm generation of scaled point kernels in water for monoenergetic electrons between 10 KeV and 1 MeV. Med Phys 32:2015-5, 2005. e-Pub 2005.
- Titt U, Vassiliev ON, Poenisch F, Kry S, Mohan R, Gillin M. Flattening filter free IMRT First experimental results. Med Phys 32:2146-6, 2005. e-Pub 2005.
- Vassiliev ON, Titt U, Kry S, Poenisch F, Gillin M, Mohan R. Dosimetric properties of photon beams from a flattening filter free clinical accelerator. Med Phys 32:1896-6, 2005. e-Pub 2005.
- Liu H, Wang X, Dong L, Vassiliev ON, Siebers J, Mohan R. Dosimetry verification for IMRT of thoracic cancers using experimental and Monte Carlo approaches. Med Phys 31:1822-2, 2004. e-Pub 2004.
- Cho S, Vassiliev ON, Liu H, Ibbott G, Mohan R. On the choice of measured depth dose data for the Monte Carlo modeling of the 18MV photon beam, shifted vs. unshifted. Med Phys 31:1906-6, 2004. e-Pub 2004.
- Titt U, Vassiliev ON, Mohan R. A flattening filter free photon treatment concept evaluation with Monte Carlo. Med Phys 31:1811-1, 2004. e-Pub 2004.
- Vassiliev ON, Liu H, Dong L, Antolak J, Cho S, Mohan R. A Monte Carlo based system for dose calculation and dosimetry QA of photon IMRT (WIP). Med Phys 30:1453-3, 2003. e-Pub 2003.
- Vassiliev ON, Peterson C, Cao W, Grosshans DR, Mohan R. Systematic microdosimetric data for protons calculated with Geant4-DNA.
- Vassiliev ON, Wang CH, Peterson C, Chang JY, Mohan R. A potential for improving the therapeutic ratio for lung SBRT through the use of FFF beams.
Books (edited and written)
- Vassiliev ON. Monte Carlo Methods for Radiation Transport. Fundamentals and Advanced Topics. Springer International Publishing, 2016.
Patient Reviews
CV information above last modified July 22, 2026