Harish Malhotra

PhD, DABR

Research Interests:

Applications of Medical Physics to cancer diagnosis and treatment

About Harish Malhotra

Biography:

Inter and Extramural Support for the Previous Five Years:

Stereotactic Body Radiation Therapy (SBRT) for Non Small Cell Lung Cancer: A Phase II Randomized Trial with a Search for Novel Predictors of Toxicity and Outcome. PI- Dr. Anurag Singh, MD [Roswell Park-Alliance grant foundation $100,000], (co-investigator).

Faculty Member:

Participated as a Faculty member in a workshop on Quality Assurance of Treatment Planning Systems jointly organized by Bhabha Atomic Research Centre and Tata Memorial Centre and held at Tata Memorial Centre, Mumbai, India during 8-10 Aug. 1996.

Panelist:

Panelist in a panel discussion on Interdependency between Technologists, Oncologists, Physicists and Patients during the IVth annual conference of the association of Radiation Therapy Technologists' of India held at Tata Memorial Centre, Mumbai, India on Oct'1, 2000.

Invited Talks:
  • Stereotactic Body Radiation Therapy (SBRT) in the Management of Prostate Cancer. 12th annual Radiation Oncology Conference for Therapists, Dosimetrists and Nurses, Roswell Park Comprehensive Cancer Center, Buffalo, New York, September 9, 2011.
  • SBRT: A paradigm shift in radiotherapy for NSC lung cancer. Upstate New York Association of Physicists in Medicine, Inc. (A Chapter of the AAPM), Spring Meeting, at Rochester General Hospital, NY, May 5, 2011.
  • SBRT in the management of non-small cell lung cancer. Physician Outreach Thoracic Oncology Program, Buffalo, New York, November 10, 2010.
  • Stereotactic body radiation therapy in the management of lung cancer. Queens University, Kingston, Canada, October 28, 2010.
  • Application of High-dose-rate brachytherapy to various anatomical sites: Roswell Park experience. Queens University, Kingston, Canada, October 28, 2010.
  • Brachytherapy in the management of gynecological cancers: Past, Present and Future. 11th annual Radiation Oncology Conference for Therapists, Dosimetrists and Nurses, Roswell Park Comprehensive Cancer Center, Buffalo, New York, September 10, 2010.
  • Experience in the Development of clinical SBRT Program. Upstate New York Association of Physicists in Medicine, Inc. (A Chapter of the AAPM), Spring Meeting, at Rochester General Hospital, NY, May 22, 2008.
  • Radiation Therapy Treatment Planning: From Sliderules to Supercomputers, Graduate Seminar Guest Speaker, University at Buffalo, NY, November, 2007.
  • A New Frontier in the Treatment of Breast Cancer: Accelerated Partial Breast Irradiation, 7th annual Radiation Oncology Conference for Therapists, Dosimeterists and Nurses, Roswell Park Comprehensive Cancer Center, Buffalo, New York, September 17, 2006.
  • Image Guided Radiotherapy (IGRT), 5th annual Radiation Oncology Conference for Therapists, Dosimeterists and Nurses, Roswell Park Comprehensive Cancer Center, Buffalo, New York, September 17, 2004.
  • Stereotactic Radiosurgery (SRS) and Radiotherapy (SRT): Rationale, Principle and Techniques. 4th annual Radiation Oncology Conference for Therapists, Dosimeterists and Nurses, Roswell Park Comprehensive Cancer Center, Buffalo, New York, September 19, 2003.
  • Head-Scatter Factors for High-Energy Photon Beams Scientific Seminar Series, Department of Molecular and Cellular Biophysics, Roswell Park and SUNY, Buffalo, NY on 7 Oct’ 2002.
  • 3D Conformal Therapy: Rationale, Planning, Dose Delivery and QA at Society for Applied Microwave Electronics Engineering & Research (SAMEER), Mumbai, India on 22 Jan'2001.
  • Planning & QA in Implementing 3D Conformal Therapy at the meeting of AROI (Maharastra Chapter) held at Inlaks & Budhrani Hospital, Pune, India on 26 Feb'1999.
  • Physical Aspects of Stepping Source Dosimetry at an International Atomic Energy Agency (IAEA) workshop on Interstitial and Interaluminal Brachytherapy, organized at Tata Memorial Hospital, Mumbai, India from 23-28 Nov'1998.
  • Quality Assurance in High Dose Rate Brachytherapy at an International Atomic Energy Agency IAEA (RCA) workshop on "Brachytherapy Source Production, Measurement and Quality Assurance", organized by BRIT (Bhabha Atomic Research Centre, India) from 18-26 Aug'1997.
  • Optimization in Radiotherapy at a workshop on Treatment Planning Systems In Radiation Therapy, hosted by Tata Memorial Centre and Bhabha Atomic Research Centre, India from 29 Sept.'94 to 1 Oct'94.

Positions

Roswell Park Comprehensive Cancer Center
  • Sr. Medical Physicist
  • Assistant Professor

Roswell Park Graduate Division University at Buffalo

  • Assistant Professor

Background

Education and Training:

  • PhD - University of Mumbai, India
  • MSc - University of Mumbai, India
  • DipRP (Diploma in Radiological Physics) - University of Mumbai, India

Professional Memberships:

  • 2011-Present - Associate Editor, Journal of Applied Clinical Physics
  • 2006-2008 - Board of Chancellor, American College of Medical Physics (ACMP)
  • 2007 - Immediate-Past-President, Upstate New-York Chapter of the American Association of Physicists in Medicine (AAPM)
  • 2006 - President, Upstate New-York Chapter of the American Association of Physicists in Medicine (AAPM)
  • 2005 - President-Elect, Upstate New-York Chapter of the American Association of Physicists in Medicine (AAPM)
  • 2004-Present - Member, Radiation Therapy Sub-Committee, American College of Medical Physics (ACMP)
  • 2004-2006 - Member, Licensure Committee, American College of Medical Physics (ACMP)
  • 1/2002-Present - Deputy Program Director, Medical Physics Residency program, Department of Radiation Medicine, Roswell Park Comprehensive Cancer Center
  • 2003-Present - Webmaster, Upstate New York Chapter of the AAPM website
  • 1997-1999 - Travel & Fellowship Convener, Association of Medical Physicists of India (AMPI)
  • 1997-1999 - Executive Committee Member, Association of Medical Physicists of India (AMPI)

Professional Experience:

  • 6-9 Nov. 1998 - Rapporteur, Poster Session in International Conference on Medical Physics, New Delhi, India

Research

Research Overview:

Brachytherapy plays an important role in the treatment of female gynecological cancers. A good part of the century long clinical experience has come from use of a tandem and ovoid applicator set which has tungsten shields in it to minimize the radiation dose and hence radiation toxicity to the nearby critical structures, rectum and bladder. Unfortunately due to practical limitations, the dose reduction due to their presence was ignored and hence the clinical experience gained relies on incorrect recorded dosage to these two vital organs. Thus the published tolerance values in literature for these structures can not be used for new set of CT/MR compatible applicators which can not have any shielding due to imaging artifacts. We are presently developing experimental methods to determine the difference in the recorded and actual radiation dosage to these organs using various detectors. This study will provide guidance to properly apply corrected constraints for rectum and bladder using CT/MR applicators.

Project 2 is based on collaboration with researchers in Carestream Health, Rochester, NY. We have successfully demonstrated a novel algorithm to use Electronic Portal Imaging Detector (EPID) to track the lung tumor in real time without requiring any external surrogate. It is very promising field which one day may help us to gate the treatments of lung patients using this technique which will be simple and yet free of less accurate external surrogates. This will also result in the reduction in tumor margin commonly employed for lung cases resulting in lower radiation toxicity to these patients.

In radiation therapy, it is very important to accurately reproduce the patient position during treatment as was used during treatment simulation. This is presently carried out using the technical information recorded manually during simulation. In another project, we are seeing the feasibility of using digital cameras along with information extracted from the patients treatment plan to verify that the patients is not only in its right position before the treatment is started but also to continuously track and monitor the patients’ position during his/her entire treatment. Our initial results are very promising in this study.

In yet another project, we are trying to find optimal beam arrangements and their mathematical characteristics to achieve an optimal treatment plan which best satisfies clinical constraints using a super computer at CCR, UB. We have already demonstrated the proof of concept in which patient specific images along with appropriate image segmentations and desired clinical constraints are fed to a cluster of computers at CCR where hundreds of combinations are tried using a process called Genetic Algorithm to come to an optimal solution. The process has been successfully demonstrated for 3D conformal therapy and we wish to extend it for intensity modulated radiotherapy (IMRT) in near future as well.

Publications

  • Bakhtiari M, Malhotra H, Jones MD, Chaudhary V, Walters JP, Nazareth D.Applying graphics processor units to Monte Carlo dose calculation in radiation therapy. Journal of medical physics 2010; 35(2):120-122
  • McCloskey SA, Tchabo NE, Malhotra HK, Odunsi K, Rodabaugh K, Singhal P, Lele S, Jaggernauth W. Adjuvant vaginal brachytherapy alone for high risk localized endometrial cancer as defined by the three major randomized trials of adjuvant pelvic radiation. Gynecologic oncology 2010; 116(3):404-407
  • Tran TA, Stanley TR, Malhotra HK, De Boer SF, Prasad D, Podgorsak MB.Target and peripheral dose during patient repositioning with the Gamma Knife automatic positioning system (APS) device. Journal of applied clinical medical physics 2010; 11(1):3150
  • May KS, Lamonica D, Nava HR, Gibbs JF, Yendamuri SS, Nwogu CE, Iyer RV, Yap JC, Warner JC, Russo RC, Malhotra HK, Flaherty L, Wilding GE, Chandrasekhar R, Khushalani NI, Yang GY, Thomas Jr CR. Association of Technetium(99m) MAG-3 renal scintigraphy with change in creatinine clearance following chemoradiation to the abdomen in patients with gastrointestinal malignancies. Journal of gastrointestinal oncology 2010;1(1):7-15
  • Schildkraut JS, Prosser N, Savakis A, Gomez J, Nazareth D, Singh AK, Malhotra HK. Level-set segmentation of pulmonary nodules in megavolt electronic portal images using a CT prior. Medical physics 2010; 37(11):5703-5710
  • Wang Z, Jaggernauth W, Malhotra HK, Podgorsak MB. Variability of marker-based rectal dose evaluation in HDR cervical brachytherapy. Medical dosimetry 2010; 35(4):269-273
  • Yap J, May KS, Jaggernauth W, Kesterson J, Daudi S, Malhotra H. Effects of dose on normal organs from intrafractional motion between the time of dosimetry planning and treatment delivery in high dose rate tandem and ovoid intracavitary brachytherapy: a CT imaging study. International journal of radiation oncology, biology, physics 2010; 78(3 Suppl. 1):S679
  • Nazareth D, Brunner S, Jones M, Malhotra H, Bakhtiari M. Optimization of beam angles for intensity modulated radiation therapy treatment planning using genetic algorithm on a distributed computing platform. Journal of medical physics 2009; 34(3):129-132
  • Oh M, Wang Z, Malhotra HK, Jaggernauth W, Podgorsak MB. Impact of surface curvature on dose delivery in intraoperative high-dose-rate brachytherapy. Medical dosimetry 2009; 34(1):63-74
  • Bakhtiari M, Kumaraswamy L, Bailey DW, De Boer S, Malhotra HK, Podgorsak MB. Using an EPID for patient-specific VMAT quality assurance. Medical physics 2011; 38(3):1366-1373
  • Hira M, Podgorsak MB, Jaggernauth W, Malhotra HK. Measurement of dose perturbation around shielded ovoids in high-dose-rate brachytherapy. Brachytherapy 2011; 10(3):232-241
  • Tran TA, Wu V, Malhotra H, Steinman JP, Prasad D, Podgorsak MB. Target and peripheral dose from radiation sector motions accompanying couch repositioning of patient coordinates with the Gamma Knife (R) Perfexion (TM).Radiology and oncology 2011; 45(2):132-142
  • Malhotra HK, Avadhani JS, deBoer SF, Jaggernauth W, Kuettel MR, Podgorsak MB. Duplicating a tandem and ovoid distribution with intensity-modulated radiotherapy: A feasibility study. Journal of applied clinical medical physics 2007; 8(3):91-98
  • Oh M, Avadhani JS, Malhotra HK, Cunningham B, Tripp P, Jaggernauth W, Podgorsak MB. Retrospective analysis of dose delivery in intra-operative high dose rate brachytherapy. Radiology and oncology 2007; 41(4):188-195
  • Wang Z, Rajagopalan B, Malhotra HK, Kuettel MR, Podgorsak MB. The effect of positional realignment on dose delivery to the prostate and organs-at-risk for 3DCRT. Medical dosimetry 2007; 32(1):1-6
  • Wu V, Podgorsak MB, Tran TA, Malhotra HK, Wang IZ. Dosimetric impact of image artifact from a wide-bore CT scanner in radiotherapy treatment planning. Medical physics 2011; 38(7):4451-4463
  • Hira M, Podgorsak M, Jaggemauth W, Malhotra H. Measurement of the effect of shielding in a tandem and ovoid applicator used in HDR brachytherapy.Medical physics 2007; 34(6):2653
  • Malhotra HK, Liu J, Tran T, Podgorsak MB. Evaluation of a 2D array planar dose verification system for IMRT dose delivery. International journal of radiation oncology, biology, physics 2007; 69(3 Suppl.):S729 (Abstract #2941)
  • Malhotra HK, Podgorsak M, Bakhtiari M, May KS, Gomez J. Inter and intrafraction set-up variation in the stereotactic body radiation therapy treatment of the lung under controlled breathing conditions measured using CBCT. International journal of radiation oncology, biology, physics 2008; 72(1 Suppl.):S618-S619
  • Oh M, Malhotra H, Podgorsak M. Monte Carlo dose verification and application of complex IOHDR geometries. Medical physics 2007; 34(6):2471
  • Wang Z, Jaggernauth W, Malhotra HK, Podgorsak MB. Variations of rectal dose estimation using rectal markers in HDR cervical brachytherapy. Medical physics 2007; 34(6):2504
  • Wang Z, Malhotra HK, Jaggernauth W, Podgorsak MB. Inverse planning simulated annealing optimization in CT-based intracavitary HDR brachytherapy for gynecological cervical cancer. International journal of radiation oncology, biology, physics 2008; 72(1 Suppl.):S586
  • Steinman JP, Bakhtiari M, Malhotra HK. Experimental measurements and Monte Carlo simulations of dose perturbation around a nonradioactive brachytherapy seed due to 6- and 18-MV photons. Brachytherapy 2012;11(5):413-420
  • Bailey DW, Kumaraswamy L, Bakhtiari M, Malhotra HK, Podgorsak MB. EPID dosimetry for pretreatment quality assurance with two commercial systems.Journal of applied clinical medical physics 2012; 13(4):82-99
  • Malhotra HK, Wu V, Wang Z, Patil S. A novel method for vaginal cylinder treatment planning: A seamless transition to 3D brachytherapy. Journal of contemporary brachytherapy 2012; 4(2):92-100