What is radiation oncology and how does it work?

Cancer is a disease that causes normal cells in the body to grow out of control. Radiation therapy uses high-energy radiation to kill cancer cells and prevent them from multiplying and growing. Radiation is generated by specialized equipment or by radioactive sources implanted inside the patient.

Radiation therapy is painless, and you do not feel anything while the treatments are given. It can be used alone in the fight against cancer or in conjunction with surgery and/or chemotherapy.

Radiation Oncology Providers

Camille M. Williams, MD


  • Radiation Oncology - American Board of Radiology

Military Service (US Army)

  • Enlisted, NBC 54B
  • Officer, LTC (Ret.) 61Q


  • American Society of Therapeutic Radiology & Oncology
  • American College of Radiology
  • National Medical Association
  • Illinois State Medical Society
  • Military Officers Association of America


  • Journal of the American College of Radiology (JACR) "Best of 2015" award for best leadership article, "Radiologists: The Unsuspecting Subject Matter Experts"


  • Kingston, Jamaica West Indies



Jacob Witt, MD


  • Radiation Oncology - Board Eligible


  • American Society of Radiation Oncology
  • American College of Radiation Oncology
  • American College of Radiology
  • Radiological Society of North America
  • Society for Neuro-Oncology


  • Wisconsin Association of Hematology/Oncology Outstanding Abstract Top Winner, 2020
  • American Radium Society Travel Grant, 2020
  • ASTRO Junior Investigator Award for Basic/Translational Science, 2019


  • St. Louis, MO


What to Expect

On the day of your first treatment, you will be positioned using your immobilization device on the treatment table. The Tomotherapy machine will then take a CT scan of the treatment region using its high-energy beam, and the images will be superimposed on your simulation CT scan. 

The actual treatment may take five to fifteen minutes to complete. You will not feel anything during the treatment, and you will not see any movement of the machine, which is shaped like a large CT scanner. During the treatment, the high-energy Linear Accelerator within the machine will be rotating in a pattern of a CT scan and will be continuously changing to shape itself to your anatomy. This process will be repeated for every one of your treatments to assure the greatest precision and accuracy. Your radiation therapists lead this process.

Our technologies and treatments

Radiation Linear Accelerator and CT-simulator – The high-precision TrueBeam medical linear accelerator (LINAC) customizes high energy x-rays or electrons to conform to a tumor's shape and destroy cancer cells while sparing surrounding normal tissue. It features several built-in safety measures to ensure that it will deliver the dose as prescribed and is routinely checked by a medical physicist.

Intensity Modulated Radiation Therapy (IMRT) - Intensity-modulated radiotherapy uses linear accelerators to safely deliver precise radiation to a tumor while minimizing the dose to surrounding normal tissue.

Image Guided Radiation Therapy (IGRT) - Image-guided radiation therapy is the use of imaging during radiation therapy to improve the precision and accuracy of treatment delivery. It is used to treat tumors in areas of the body that move, such as the lungs. 

Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiotherapy (SBRT) - Stereotactic radiosurgery is a non-surgical radiation therapy used to treat functional abnormalities and small tumors of the brain. It can deliver precisely-targeted radiation in fewer high-dose treatments than traditional therapy, which can help preserve healthy tissue. When SRS is used to treat body tumors, it's called stereotactic body radiotherapy.

Radiation FAQs

Q. Will I lose my hair?
A. You will only lose your hair if we are treating in the head region.

Q. Is it safe to be around other people while receiving radiation treatments?
A. Yes. While receiving external radiation treatments, you are not at risk of endangering others.

Q. How long will my treatment session last?
A. Each treatment session will last between 15 and 20 minutes.

Q. Do I have to come every day?
A. Yes. Treatments are given Monday through Friday.

Q. How tired will I be?
A. Fatigue is a side effect of radiation, but most people are able to continue with their daily activities.

Q. What are some of the other common side effects to radiation treatment?
A. Since radiation treatment is localized to the area of your body with the tumor, your side effects generally are limited to that area as well. Your skin might be red, irritated or swollen at the treatment site. Please talk to your doctor about the side effects you might experience based on the location of your tumor.

Q. Can I drive myself?
A. Most patients are able to drive themselves to treatment, but check with your physician to make sure it is safe for your particular case.

Q. Does radiation therapy hurt?
A. No. Radiation therapy is much like receiving an X-ray. You will not feel anything while receiving treatment.

Q. Will I have to wait long before getting an appointment to see the doctor?
A. No. Most new patients are able to schedule an appointment within one week of calling.

Q. What happens after my radiation treatment is finished?
A. Every patient’s treatment plan is unique. Talk to your doctor to find out what your next steps will be. Remember, you are not alone in this fight. We are always here for you after treatment.

Quotes from our patients

Succinctly stated-Outstanding care! Leadership and team were unparalleled! After being referred, I was contacted by team and met with Dr. Witt. He impressed me with his professional bearing, superb knowledge base, preparedness, and listening skills. Clearly his leadership guides an excellent support staff/team. Compassionate, competent, caring staff. I was impressed with the team's "can do attitude" and impressive skill set! They "had my back" and I know it! Best of the best!!

I want to thank you for the excellent way my treatment went. One of the best teams I have been around. Keep up the good work.

My treatment far exceeded my expectations. The doctor, nurses and technicians, and counselors all treated me with respect, were courteous, very helpful and responsive to all my concerns and questions and were totally professional, yet kind and friendly when treating me. Starting this type of treatment is scary but having this team of caring providers made it better than I had anticipated. Would highly recommend this team to any facing this type of cancer treatment. Also, the receptionist greeted me every day with a friendly word and a smile-great way to start each session.

Excellent staff!! Dr. Williams is a pure joy! I will miss all involved in my treatments. Thank you and God bless you all.