Ron Lalonde, PhD, DABR

  • Clinical Associate Professor, Radiation Oncology
  • Chief Physicist, UPMC Shadyside Hospital and Associate Chair
  • Medical Physicist, UPMC Hillman Cancer Center

I manage radiation oncology physics at UPMC Shadyside and provide oversight on research and teaching programs at all UPMC Hillman Cancer Center locations. I sit on the regional coordinators committee and on the committee of the UPMC Medical Physics Residency Program. My interests include radiosurgery planning and QA, IMRT planning, and knowledge-based planning systems. In addition, I am also Chief of Physics for D3 Oncology Solutions, a clinical physics consulting company owned by UPMC.

Teaching activities:

I supervise sections of the medical physics residency program and also teach several lectures in the radiation oncology residents physics program. I developed, direct, and teach in a bi-monthly radiosurgery course presented to UPMC staff and outside clients. I developed, direct, and teach a regular class in motion management to UPMC staff and outside clients.

Representative Publications

Bernard ME, Clump DA, LaLonde R, Beriwal S. Radiation therapy for locally advanced lung cancer. Transl Cancer Res 2015;4(4):356-371, 2015.

Quan, K, Xu, K, Zhang, Y, Clump, A, Flickinger, J, Lalonde, R, Burton, S and D Heron, Toxicities Following Stereotactic Ablative Radiotherapy Treatment of Locally-Recurrent and Previously Irradiated Head and Neck Squamous Cell Carcinoma, Sem. Rad. Onc. 26, No. 2, pp 112-119, 2016.

Quan K, Xu KM, Lalonde R, Horne ZD, Bernard ME, McCoy C, Clump DA, Burton SA, Heron DE., Treatment Plan Technique and Quality for Single-Isocenter Stereotactic Ablative Radiotherapy of Multiple Lung Lesions with Volumetric-Modulated Arc Therapy or Intensity-Modulated Radiosurgery, Front Oncol. 2015 Oct 6 (5): 213.

Research Grants

Research grants and/or contract activity:

Currently principle investigator (20% effort) for a private grant from Varian Medical Systems, entitled “Use of RapidPlan System to Evaluate the Effects of Treatment Margins on Plan Quality”, 2015-2016, $125K dollars in direct funding.

Summary of research:

Background: The ability to spare organs at risk (OARs) near the planning target volume (PTV) depends on the amount of overlap of the OARs with the PTV margins around the target.  PTV margins may be reduced by various levels of immobilization and localization, but these may be expensive, invasive or uncomfortable, and may also increase patient setup and treatment duration.  The goal of this project is to devise a simple way to identify those patients who would most benefit from reduced planning margins.

Research Methods: The Varian RapidPlan™ knowledge-based planning module was used to estimate doses for VMAT prostate treatment plans (total dose 78 Gy) with differing sizes of PTV margin corresponding to 1) weekly imaging only (1.0 cm margin), 2) daily CBCT (0.5 cm margin), 3) daily CBCT with intrafraction monitoring of prostate motion (0.3 cm margin).  The estimated doses were then compared with actual treatment plan doses (AAA dose calculation) generated using the RapidPlan™  optimization constraints, to confirm that the estimated doses were accurate and achievable in these plans.  Treatment plan doses were then compared against QUANTEC dose limits for bladder, rectum and penile bulb for all three sizes of margin.

Results: The OAR dose goals achieved in optimization were within or below the estimated range generated by the planning system in 100% of plans, with most doses at the lower end of the RapidPlan DVH estimation range. The final plan OAR doses were approximately 5% greater after plan re-normalization to improve target coverage.  63% of the treatment plans were able to achieve QUANTEC dose goals to the bladder and the rectum even with 1.0 cm margins. 90% of the plans were able to achieve QUANTEC dose goals to the penile bulb with 1.0 cm margins and 100% of the plans were able to meet all QUANTEC goals with 0.5 cm margins.

Conclusions: The knowledge-based planning system was able to accurately predict the achievable doses in treatment plans within 5%.  In this study, it was not necessary to reduce planning margins to less than 0.5 cm to achieve clinical OAR sparing. This estimation method may allow a quick and simple way to identify patients who will benefit from enhanced immobilization or localization techniques and target them appropriately.

Future work: In future, we will extend the present study to other treatment sites (lung, pelvis, head and neck).  We are also currently investigating the impact of daily organ deformation on these results.