A community driven practice serving the Metro East for over two decades.

For over 2 decades, our facilities have been dedicated to offering state of the art Radiation Therapy services in the Metro East in a caring and positive environment.


Mohamed Megahy, Ph.D, MD

Dr. Megahy received his Ph.D. in Pharmacology from University of Illinois, Chicago in 1968. He attended medical school at the University of Alexandria, Alexandria, Egypt, graduating in 1978, and then completed his residency in Radiation Oncology at The University of Chicago where he was Chief Resident through 1984. He arrived in the Metro-East in 1987 and opened his first Radiation Oncology practice in Maryville next to Anderson Hospital in 1992. Dr. Megahy, who is on staff at St. Elizabeth’s and Memorial Hospitals in Belleville, believed that it was imperative to offer patients and their families treatment options close to their communities. As such, he expanded his practice to Belleville in 1998 and Breese in 2003. All in all he has served patients in the Metro-East for 20 years.

Our offices have been serving the Metro East Community for over two decades.  Dr. Megahy and staff have always been, and remain committed to providing their patients with the highest quality radiation oncology services.

Please do not hesitate to call to schedule an appointment or send an email through the link on this page.

Radiation therapy, radiotherapy, or radiation oncology, often abbreviated RT, RTx, or XRT, is the medical use of ionizing radiation, generally as part of cancer treatment to control or kill malignant cells. Radiation therapy may be curative in a number of types of cancer if they are localized to one area of the body. It may also be used as part of adjuvant therapy, to prevent tumor recurrence after surgery to remove a primary malignant tumor (for example, early stages of breast cancer). Radiation therapy is synergistic with chemotherapy, and has been used before, during, and after chemotherapy in susceptible cancers.


Radiation therapy is commonly applied to the cancerous tumor because of its ability to control cell growth. Ionizing radiation works by damaging the DNA of cancerous tissue leading to cellular death. To spare normal tissues (such as skin or organs which radiation must pass through to treat the tumor), shaped radiation beams are aimed from several angles of exposure to intersect at the tumor, providing a much larger absorbed dose there than in the surrounding, healthy tissue. Besides the tumor itself, the radiation fields may also include the draining lymph nodes if they are clinically or radiologically involved with tumor, or if there is thought to be a risk of sub-clinical malignant spread. It is necessary to include a margin of normal tissue around the tumor to allow for uncertainties in daily set-up and internal tumor motion. These uncertainties can be caused by internal movement (for example, respiration and bladder filling) and movement of external skin marks relative to the tumor position.

Radiation Oncology







Our team is committed to supporting you in every step of your journey.

  • CT Simulation:

    A Cat Scan procedure used during the treatment planning stage to identify the exact location and size of the area that needs treatment.

  • Three Dimensional Conformal Therapy:

    A type of external beam radiation that is shaped to fit the profile of the target.  This method allows conforming of the beam to the shape of the tumor, which reduces radiation to the surrounding healthy tissue.

  • IMRT:

    Intensity-modulated radiation therapy is an advanced type of radiation therapy.  It uses multiple small beams of varying intensities to focus on the tumor.  The goal is to reduce exposure to healthy tissue and minimize side effects.

  • Gamma Knife Stereotactic Radiosurgery:

    A type of radiation therapy that treats tumors and abnormalities of the brain.  Although the name indicates a surgical procedure, there is no incision.  This form of radiation uses specialized equipment that focuses hundreds of beams to a specific target.   The procedure is usually a one-time therapy completed in a single day.

  • Quadramet:

    An FDA approved radiopharmaceutical given through venous injection used for relief of bone pain in patients with metastatic bone lesions.

  • Radioactive Iodine:

    Usually given in pill form.  The purpose is to treat hyperthyroidism in people with overactive, noncancerous thyroids.

  • Prostate Brachytherapy:

    A form of radiation that requires a surgical procedure.  The procedure involves placing devices/seeds containing radiation into the prostate gland close to the cancer cells.

  • Xoft Electronic High Dose Rate Brachytherapy:

    A high dose rate treatment that is used for qualifying breast cancer patients.   A balloon device is inserted into the lumpectomy cavity.  A miniature xray source is placed into the balloon and radiates the tumor bed with an xray source rather than radioisotopes.  This procedure is usually performed twice a day for five days.




"I can't say enough about the care and concern I received from Dr. Megahy and his staff...I felt like I was the only person they were treating"

Linda T.

Belleville Patient

"I was very well satisfied with everything.  The staff was great and helpful in every matter.  I would reccomend your doctors and staff to anyone in need of Radiation"

Mary C.

Maryville Patient

"I wish all medical facilities were like yours.  It was pleasant at all times.  Everyone was concerned and cared about every patient"

Sharon S.

Belleville Patient

"Excellent quality care.  Radiation staff always professional, compassionate and on time.  Never felt rushed or uneasy, able to ask them anything.  Whole staff was great.  Well Oiled team!"

Sharon U.

Maryville  Patient

"The experience was the best I have had in any medical procedure.  All aspects of the treatments were handled well and professionaly.  The staff was an asset to their profession..."

Neal H.

Maryville Patient

"Guess the way I look at my experience is you all became a loving ,caring, understanding part of my own family.  I cannot say enough good things about all of you.  I love you guys!"

Dena L.

Breese Patient

We take our commitment to patient care very seriously, here are some of the comments former patients have shared

Frequently Asked Questions (FAQ)

Will radiation make me cancer free?

The goal with radiation is to cure your cancer unless it is in advanced stages or has already metastasized (spread).  Sometimes the goal of radiation is to eliminate pain.


Does radiation cause other cancers?

Radiation slightly increases the risk of forming a secondary cancer.  However, for many people radiation cures the current cancer.  So the benefits far outweigh the risks.


Is radiation painful?

Radiation is a painless procedure.  Depending on the area being treated some people may experience skin irritations, difficulty eating, painful or frequent urination, or bowel changes once well into treatment.  Talk with your doctor regarding possible side effects.


Does radiation therapy cause infertility?

Radiation is very local, unless the area being treated is in the reproductive area it will not cause infertility.  However; radiation to the reproductive system may decrease the chances of having children.  Talk with your doctor before treatment starts for options of preservation.


Will radiation make me lose my hair?

Radiation is very site specific so hair loss will only be experienced in the area we are treating.


Should I avoid people after having radiation?

External beam radiation does not leave any radiation behind.  There is no need to avoid people after your daily treatments.  Internal or seed implants will require a specific period of time where you should avoid contact with people.  Your physician will be able to give you the recommended time.


Will I be in the treatment room by myself?

Yes, if the therapist were in the room all day every day they would be exposed to dangerous levels of radiation over time.  Even though you are in the room by yourself you will constantly be monitored through and audio and video system at all times.


Will I be able to drive to my appointments?

Most people can drive themselves unless instructed otherwise by physician.  If you are not feeling well you may want a family member or friend give you a ride.


What happens if I miss an appointment?

We encourage you to complete your course of treatment without missing a day.  We will accommodate you with change in times if that will help you make your appointment.  However; if you miss we will just add a day.  Your prescribed dose will remain the same.


Will radiation burn me?

Skin reactions are a common side effect of radiation.  Sometimes it may look and feel like a sunburn.  Your radiation therapist and the physician will keep an eye on this for you and help you treat the symptoms.


Can I shave?

It is not recommended that you shave in the area that we are treating.  For example; if you are having your right breast treated we suggest that you not shave your right arm pit area.  Shaving could cause your skin to become more irritated.




Forms & Information


Belleville (618) 277-5882Maryville (618) 288-8900Breese (618) 526-7100


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