General Patient Information


During your course of radiation therapy Dr. Tokita will see you. As the department director, Dr. Tokita will be involved in the care of every patient. He will review, outline and supervise the planned course of treatment.

Listed below are terms often used by the staff and physicians. You may want to reference this list at a later date.

CONSULTATION/HISTORY AND PHYSICAL/WORK UP: These are synonymous terms used by the radiation oncologists and other physicians for the initial evaluation. A portion of the consultation is spent with you, the patient, for a history and physical exam. The other portion, which you don't see, is the review of your case with your referring physicians, comparing and reviewing pertinent studies and planning your course of treatment.

SIMULATION/INITIAL SET-UP/LOCALIZATION: After the physician has identified a specific area to be treated with radiation, one of the therapists will take a series of x-ray films to specifically outline this area. This procedure is done in our CT/Simulator room. These areas will be localized on your body utilizing a series of different techniques, which may include taping wires to the skin, marking on the skin with a felt tip pen, or using the wires available within the x-ray machine to shadow marks on the skin. The simulator machine is similar to a diagnostic x-ray machine, but it also possesses the ability to reproduce the exact dosimetry of a treatment-planning computer. Part of the simulation procedure may include a limited CT scan to assist the physicist with exact measurements and densities. Once your treatment area is outlined and approved by the doctor tattoos will be given to allow the therapist to reproduce the markings on a daily basis. The tattoos are about the size of a pinhead and are placed in the centers and corners of the treatment field.

PHYSICS CHECK: A Medical Radiation Physicist is one of the members of our team. Although you don't see him/her personally, they play an integral part in the planning of your treatment. Their expertise includes checking the set-up, calculations, computer dosimetry, calibrations, as well as monitoring the everyday functions of the machine.

DOSIMETRY/TREATMENT PLANNING: Is the complex calculating and alignment of radiation beams according to physician's prescription. The measurements and CT images relating to your specific case are input into a treatment-planning computer. In return, the computer will give appropriate parameters for the treatment machine. The physicist, Dosimetrist, therapist and physician do this. This whole process can take from 1-1/2 hours to 6 hours, depending on the complexity of the plan.

RADIATION THERAPISTS: Our therapists are fully trained in the highly specialized field of Radiation Oncology. This involves all aspects of patient care including simulations, first day set-ups, port films, daily treatments, treatment planning, side-effect management, skin and dietary counseling. Throughout your course of treatment, you may meet several of our therapists. Please do not hesitate to ask questions or review any situation that may come to mind during your course of treatment.

LINEAR ACCELERATOR (LINAC): The linac is an electrical device used to produce high energy X-rays which are manipulated to deliver external beam radiation treatments for patients with cancer. The produced x-ray beam comes out of the part of the accelerator called the gantry. The gantry rotates around the patient while delivering the radiation treatment. Cancer Center of Irvine has a Varian 23iX Linear Accelerator with 2 energies and x-ray 6 Million Volts (MV) and 18 Million Volts (MV). The 23iX also has electron capabilities of 5 different energies ranging from 6 Million electron Volts (MeV) to 16 Million electron Volts (MeV). The physician and physicist will select the appropriate energy for your treatment.

EBRT: external beam radiation therapy is a method for delivering high energy x-rays or electron beams to a patient's tumor. Beams are usually generated by a linear accelerator and targeted to destroy cancer cells while sparing surrounding normal tissue. With external beam radiation treatments patients do not become radioactive during or after treatments.

IGRT: image guided radiation therapy is a method of external beam radiation therapy that incorporates imaging techniques during each treatment session. The use of imaging during radiation therapy ensures radiation beams to be narrowly focused at the treatment area, and improves the precision and accuracy of treatment delivery. When undergoing IGRT, high quality images are taken before radiation therapy treatment sessions.

CBCT: cone beam computed tomography is a medical imaging technique consisting of X-ray computed tomography. Most frequently used type of imaging for patient setup and adaptive re-planning. This low dose imaging technique is taken prior to treatment and will allow the therapists to visualize patient internal anatomy and precisely pin point the targeted area for treatment.

PORT FILMS/BEAM FILMS: Are taken prior to treatment and routinely during the course of treatment. The films are a way for the physicians to verify the field of treatment for accuracy and document the area treated.

BOOST: This refers to a planned change in the original field set-up. This may be due to the tolerance dose of a specific structure, previous treatment, change in radiation field size, or further treatment to a smaller area. The Boost may require a second CT scan to be ordered, a Simulation, or a Clinical set-up in the treatment room. The therapist will be able to explain details as to the purpose of your "boost plan" for your specific case.

WEEKLY: Dr. Tokita or one of his nurses will meet with you weekly, at which time they will check on your progress and management of side effects through therapy and answer any new questions that may arise. Please do not hesitate to ask to see them any time as the need arises.

CHART ROUNDS/REVIEW: Is conducted weekly for the purpose of analyzing each patient's chart in great depth. We review the treatments of the past week and plan for the future week. It allows Dr. Tokita to discuss his findings of the weekly patient visits with the staff.

EMERGENCY PHONE CALLS: Dr. Tokita is always available. You may reach him at the office daily at (949) 417-1100, or after hours at (949) 502-5445. You may also contact your referring physician for assistance if needed.

There are many other terms and phrases used in the Radiation Oncology Department that may be confusing. Please do not hesitate to ask any one of the members of the Department to explain them for you. We believe your understanding of the treatments is important to your getting well.