Radiation Oncology

Patient Support & Resources

Frequently Asked Questions about Radiation Therapy

How does radiation therapy work?

Radiation therapy uses high energy X-rays to damage the DNA of the tumor cells, thereby preventing them from dividing, growing and spreading. During radiation therapy, normal cells are damaged as well. However, normal cells are better able to repair this radiation damage. In order to give normal cells time to heal and to reduce a patient's side effects, radiation treatments are typically given in small daily doses, five days a week, over a six- or seven-week period.

How is radiation therapy administered?

There are two main types of radiation therapy: external and internal radiation therapy.

During external radiation therapy (which may also be called X-ray therapy, cobalt therapy, proton therapy, or intensity-modulated radiation therapy (IMRT) a beam of radiation is directed at the treatment site from outside the body. This is typically done using a machine called a linear accelerator.

Internal radiation therapy (also called brachytherapy or implant therapy) involves the surgical placement of a source of radioactivity directly into the tumor or inside the body near the tumor. This may be done by implanting "seeds" (small pieces of the radioactive substance) directly into the tumor or in the space around the tumor. This delivers very intense radiation to a small area of the body and limits the dose to normal tissue.

Internal radiation therapy allows the doctor to give a higher total dose of radiation in a shorter time than is possible with external treatments. The radioactive substances used (also called the "radiation source") typically include cesium, iodine, and iridium. Depending on the substance, the implant may be temporary or permanent, although the effect wears off over time in all cases.

What are the benefits of radiation therapy?

Radiation therapy is an effective means of treating many types of cancers in almost any part of the body. Nearly two-thirds of all cancer patients receive radiation during the course of their treatment. For many patients, radiation is the only treatment needed.

There are several benefits of using radiation therapy. Radiation therapy:

  • Is a localized treatment, meaning it targets a specific area of the body.
  • Can be used in the management of cancers that cannot be treated successfully by surgery or chemotherapy alone.
  • Can be used following surgery to eradicate existing cancer cells that couldn't be removed.
  • Can reduce the size of a tumor so that it can be more safely removed or treated with chemotherapy during surgery.
  • Can offer permanent control of a tumor thereby reducing pressure, bleeding, pain and other distressing symptoms, and enhancing quality of life.
  • Can be combined with chemotherapy to enhance the effectiveness of both treatments.
Are there any risks or side effects associated with radiation therapy?

As with all other cancer treatments, there are risks for patients who undergo radiation therapy. Radiation used to damage or destroy cancer cells may also hurt normal cells. When this happens, patients may experience side effects.

Many side effects of radiation therapy are considered acute or short-term because they occur during treatment and tend to resolve within a few months of the completion of therapy. When side effects do occur, they vary and depend upon the individual and the location of the cancer. The most common side effects of radiation therapy include:

  • Skin reaction at the site of treatment.
  • Hair loss at the site of treatment.
  • Nutritional problems.
  • Fatigue.
  • Neutropenia (a reduction in white blood cells).

At Penn Radiation Oncology, patients meet with a doctor weekly. This offers the opportunity to discuss any side effects that patients may be experiencing and implement the necessary interventions to alleviate discomfort. If side effects become severe, treatment may be put on hold to allow the tissue time to heal before continuing.

Sometimes, patients will develop a chronic side effect as a result of their radiation therapy. These problems may arise years after treatment. Typically, these side effects are closely related to the area of the body that was treated and include:

  • Memory impairment, confusion, personality changes (all with brain irradiation).
  • Development of another cancer as a result of tissue damage.
  • Cataracts.
  • Dental problems.
  • Heart problems (high blood pressure, high cholesterol levels).
  • Infertility.
  • Hypothyroidism.
  • Respiratory problems.
  • Gastrointestinal problems.

Patients are therefore monitored for extended periods of time to evaluate and treat any late toxicity.

Does radiation therapy hurt?

No, radiation therapy does not hurt when it is being administered. But the side effects that people may experience from radiation therapy can cause pain or discomfort.

Who administers radiation therapy?

Radiation therapy requires a team approach that includes the:

  • Radiation oncologist who has special training in using radiation to treat disease and who prescribes the type and amount of radiation a patient receives.
  • Medical physicist who makes sure that the equipment is working properly and that the right dose of radiation is delivered.
  • Dosimetrist who works closely with the radiation oncologist and medical physicist to develop the treatment plan.
  • Radiation oncology nurse, who provides nursing care and teaches the patient about the treatment and how to manage side effects.
  • Radiation therapist who sets the patient up on the treatment table and operates the radiation equipment under the supervision of the radiation oncologist and medical physicist.
  • Social worker who addresses any social or psychological needs that may arise prior to, during or after treatment.
What qualifies a doctor to administer treatment?

All of Penn's radiation oncologists have completed an American Council for Graduate Medical Education-accredited residency program. All physicians are board-certified or in the process of board certification by the American Board of Radiology in the specialty of Radiation Oncology. Every member of the Penn Radiation Oncology team specializes in a specific tumor site and has developed additional expertise in treating tumors in those select areas. Many of Penn's radiation oncologists are nationally and/or internationally recognized as leaders in the field.

How long does treatment take?

Depending upon the treatment protocol, a patient can expect to be at Penn Radiation Oncology for five consecutive days a week for several weeks.

Where should I stay while undergoing treatment?

There are many local options for patients who require lodging while undergoing their radiation treatment. For a complete listing, as well as other useful information, please refer to the Visitor Information page. Penn Radiation Oncology's social workers can also assist you with lodging.

Should I bring anything with me to my treatment sessions?

Patients are not required to bring anything with them to their treatments. However, individual patients may receive special instructions regarding preparation for their treatment.

Within the waiting area at Penn Radiation Oncology, patients have access to a wide range of reading material as well as several desktop computers with Internet capability. Patients who wish to use their own laptop computers may take advantage of Penn's free wireless Internet.

Where should I go for my treatment?

Patients arriving for treatment at the Ruth and Raymond Perelman Center for Advanced Medicine should report to Penn Radiation Oncology, located on the concourse level.

Where should I park for my treatment?

Patients receiving treatment at Penn Radiation Oncology at the Perelman Center have access to free valet and self parking that is convenient, safe and customer-friendly. Parking garages and valet parking are available at the Perelman Center, the Hospital of the University of Pennsylvania, and Penn Tower. For more information and a map of parking locations, please refer to the Visitor Information page.

May I participate in normal activities during treatment?

Patients should check with their radiation oncologist to review their level of normal activities permitted.

What about returning to work?

Many people continue to work during their treatment. However, for jobs that are physically strenuous, then it may be necessary to switch activities or abstain from work until the patients regain their strength.

What is Positron Emission Tomography (PET or PET Scan)?

Some of the latest advances in radiation diagnostics help radiation oncologists at Penn Medicine accurately map the location of the cancer and precisely deliver radiation to the cancer cells.

PET scans create computerized images of chemical changes, such as metabolism, that take place in tissue. This helps in locating a tumor, because cancer cells have a higher metabolism than other tissues in the body.

Through the combined matching of a CT scan with PET images, there is an improved capacity to discriminate normal from abnormal tissues. Radiation oncologists also use the PET images to check the effectiveness of radiation treatments on the cancer cells.

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