The Important Role of Dosimetrists in your Proton Therapy Treatment Plan

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It only takes a few minutes for patients to receive their daily proton therapy treatment.  However, for each treatment course there has been hours of prior planning to develop the best treatment plan according to the radiation oncologist’s prescription.  The treatment plan comprises of the exact dose and beams and patient positioning aspects required to deliver the dose to the target volume.

Protons are positively charged particles that have a unique range of penetration into the patient’s body.  This is characterized by the Bragg Peak.  The Bragg Peak occurs at the point where the highest dose of radiation is delivered to the patient’s body.  Dosimetrists use physics software tools to determine how to formulate the proton beam i.e. the beam energy and intensity in order for the Bragg Peak to occur at the site of the tumor.  With protons, there is minimal entrance dose and no exit dose.  The Bragg Peak happens at the tumor because the protons stop which makes proton radiation therapy so precise.

The dosimetry team works closely with the medical physicists and the radiation oncologists to determine the exact physics behind every single proton beam received by patients.  No two treatment plans are the same.  Treatments are completely customized based on the individual’s tumor, body and other factors.

One of the most important goals for our dosimetry team is to find the best treatment plan for every individual patient that minimizes the radiation to healthy tissue and critical organs.  They do this using pencil beam scanning technology, where the beam of radiation, which is just millimeters wide, are controlled in position and depth in order to bypass nearby organs and targeting the tumor directly.  The precision of proton therapy pencil beam scanning in conjunction with the dosimetrists who prepare the best treatment plans ensures that patients receive less radiation outside the target areas and therefore reduces side effects while maintaining their quality of life both during and after treatment.

Provision’s team of Dosimetrists in Knoxville is led by Valerie Coffman who is a board-certified dosimetrist with more than 5 years of experience in proton dosimetry.  Including Valerie, Provision has a team of 4 board certified dosimetrists, two dosimetrists that just finished dosimetry training at provision and two dosimetry interns.  The dosimetry team works in close collaboration with 4 board certified Medical physicists, two residents and one physics assistant.

 

In Nashville, Provision’s team of dosimetrists is led by Joe Simmons who is a board-certified dosimetrist with more than 15 years of experience in proton dosimetry. Including Joe, the Nashville team has 3 board certified dosimetrists and one dosimetry intern working with 3 board certified medical physicists and one physics assistant.

Together, our team of medical dosimetrists and physicists work to ensure that our patients receive the best treatment plans possible based on the prescribe radiation dose from our radiation oncology team.