Treatment planning involves an extensive process to customize each patient’s external or internal radiation treatment course. The goal is to precisely deliver as much curative radiation as possible to the tumor, with as little dose as possible to the surrounding normal tissue.
The treatment planning section, also known as medical dosimetry, is a clinical division within the Radiation Physics section of Therapeutic Radiology. The section supports seven clinical physicists and nine medical dosimetrists all with advanced training and experience. The entire staff is interested in, and routinely explores, the development and implementation of new techniques in the delivery of cancer treatment.
Several recent technological developments have enhanced this process. Prior to treatment, the patient’s planning begins with sophisticated imaging studies (CT-PET, MRI) that are merged with the patient’s anatomical images taken on the radiation therapy department’s CT-Simulator. This unit duplicates the geometry of the radiation treatment machines and provides a three dimensional (3D) view inside the patient’s body. These images are used to localize the tumor sites and plan the patient’s treatment.
The radiation oncologist develops a treatment design, writes a prescription outlining the treatment course, and consults with the treatment planning team. Multiple factors are considered at this point, including the type and size of tumor, pathology, location, nearby anatomical structures, age, overall health, previous treatment, and the available treatment machine characteristics, among others.
At their disposal are the latest developments in treatment planning and treatment delivery systems. These include 3D treatment planning computers that allow the physicist and medical dosimetrist to plan a variety of complex cases including IMRT. Additionally, this detailed and specialized information is accurately reproduced, documented and transferred to the treatment machines.