External beam radiation therapy is used to shrink tumors and kill or slow the growth of cancer cells. Radiation damages the DNA of both malignant and healthy cells, but healthy cells are better able to repair the damage. Some cells die quickly due to apoptosis while others will have to go through several cycles of mitosis before they die, which is why it may take days to weeks for some tumors to shrink. 

Radiation is often used in conjunction with chemotherapy, immunotherapy, and/or surgery. While it is used as an attempt to treat and stop cancer growth, it may also be used in palliative care to reduce pain from bone metastases, relieve spinal cord compression, reduce lesions, control bleeding and relieve superior vena cava obstruction.

Note that there is a “lifetime limit” to how much radiation an area of the body can receive. For this reason, a patient with recurrent cancer may not be able to have radiation to that area if they received radiation to that same area in the past. And that’s because radiation has some pretty serious risks and side effects. 

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External Radiation Therapy Basics

Prior to the patient’s first radiation treatment, they will first attend a simulation procedure appointment. In this procedure, the treatment areas are defined and marked with very small tattoo dots. A mold of the treatment area may be made and immobilization devices may be used to ensure patient stability throughout the procedure. Imaging studies such as X-ray, CT, MRI and PET scans may also be utilized to plan radiation treatment. 

As its name suggests, external beam radiation is administered from an outside source. A machine called a linear accelerator aims radiation at the target area in doses 1000 times greater than a standard X-ray. Treatment regimens can vary. Some patients will get one dose of radiation while others will receive consecutive treatments for a number of weeks.

There are several types of radiation therapy:

  • Three-dimensional conformal RT (3D-CRT) – The radiation dose is calculated in three dimensions to minimize exposure to other body structures and accommodate the shape of the tumor.
  • Intensity-modulated RT (IMRT) – This is an advanced type of 3D-CRT, which uses “nonuniform” radiation beam intensity to get the maximum radiation dose to the tumor while exposing surrounding tissue as little as possible. This type of radiation therapy allows for stronger doses to parts of the tumor and weaker doses to other areas, thereby limiting exposure to normal tissues.
  • Image-guided RT (IGRT) – This type of radiation therapy uses daily imaging (usually CT scan) to reduce margins around the target area and focus in on tumor tissue. A subset therapy called image-guided adaptive radiation therapy accounts for changes to anatomy as the tumor size changes during treatment.
  • Stereotactic body RT (SBRT) or stereotactic radiosurgery – This type of therapy involves large doses of radiation with a short course of treatment, typically one to two weeks. It is often used for brain tumors and delivers a very precise dose of radiation to the target tissue. 
  • Charged particle radiation – Uses heavily charged particles for patients who need high doses of radiation near critical organs such as the brain. It is typically used for small, well-defined tumors.
  • Spatially fractionated radiation therapy (SFRT) – This is a non-uniform dose of radiation utilized to treat the tumor without damaging surrounding tissues. It is often used for large malignant tumors needing high doses of radiation.

Complications of Radiation Therapy

Because this type of therapy utilizes a high dose of radiation, it’s no surprise that studies have shown that individuals who undergo radiation therapy are at higher risk for developing leukemia, breast cancer, thyroid cancer, and other cancers later in life.

Additionally, the complications of radiation therapy are also quite serious and include:

Radiation-induced fibrosis: Depending on the treatment site, fibrosis (which is a buildup of fibrin) can develop in the lungs, GI tract, GU tract, muscles, internal organs and the skin. While the risk is higher with higher doses of radiation, the heart is especially susceptible to fibrosis. This condition, called radiation-induced myocardial fibrosis (RIMF) can result in heart failure, reduced ejection fraction, and sudden cardiac death.

Radiation-induced pulmonary fibrosis can cause a persistent dry cough and shortness of breath with symptoms often not seen until 6 to12 months after completion of therapy.

Radiation-induced fibrosis can also cause a wide range of symptoms based on the location and may include restricted joint motion, lymphedema, pain, GI fistulas or strictures, brittle and weak bones, muscle wasting, neck pain, and dysphagia.

Treatment for this complication includes addressing the symptoms with things like early physical therapy, Louis-Paul Guitay massage, vaginal dilation and estrogen cream, lymphatic drainage, speech therapy, and analgesic medications. Hyperbaric oxygen therapy is currently being studied and studies suggest it may be helpful in reducing peripheral nerve damage and lymphedema.

Pharmacologic therapy involves the use of pentoxifylline, a medication that enhances microvascular blood flow in combination with tocopherol (Vitamin E). 

Infertility: The ovaries and testicles are very sensitive to damage caused by radiation therapy, which can lead to infertility. Note that it’s not just pelvic or lower spine radiation that can cause damage. Therapy to the head or neck can damage the hypothalamus or pituitary which can lead to gonadotropic deficiency and hyperprolactinemia (a condition that can cause infertility and other fertility related problems). Patients who wish to have children after radiation therapy may wish to preserve sperm, eggs, or embryos.

Gastrointestinal toxicity: Complications in the GI tract can occur after thoracic, abdominal and pelvic radiation therapy. These include esophagitis, gastritis, and enteritis. 

Esophagitis can cause difficulty swallowing (dysphagia), chest pain, and in severe cases, the formation of a tracheoesophageal fistula which can lead to acute lung injury, recurrent pneumonia and even ARDS.

Patients with gastritis may experience the formation of ulcers, nausea, vomiting, dyspepsia, abdominal pain and loss of appetite.

Enteritis can lead to perforations and ulcerations as well as diarrhea, abdominal cramps, nausea and vomiting, loss of appetite and malaise.

Cardiac toxicity: In addition to cardiac fibrosis, radiation therapy can also cause cardiac toxicity. This can lead to conditions such as CAD, arrhythmias, pericarditis, valve dysfunction, cardiomyopathy, and heart failure.

Now that you have an overview of external beam radiation, let’s go through how to care for a patient using the Straight A Nursing LATTE method.

L: How does the patient LOOK?

Patients may have a wide variety of symptoms depending on the type of cancer being treated, the area undergoing radiation, and the cumulative dose of radiation. General side effects of external radiation therapy include edema in the target area, fatigue, hair loss in the treatment area, poor PO intake, dehydration, and low blood counts. The skin also suffers the effects of radiation (radiation dermatitis) and can be red, tender, and irritated with blisters, dryness, flaking, itchiness and peeling. 

Specific areas of the body can have varying symptoms when targeted by radiation:

  • Abdominal radiation therapy: nausea, vomiting, abdominal cramps, diarrhea
  • Brain radiation therapy: headache, hair loss, hearing loss, memory issues, speech changes, seizures, cerebral edema, nausea/vomiting, cataracts, decreased LOC
  • Head and neck radiation therapy: mucositis, sores in mouth or throat, dry mouth, dysphagia, taste alterations, earaches, tooth decay, gingival edema, jaw stiffness, laryngitis, oral candidiasis
  • Thoracic/chest radiation therapy: esophagitis, sore throat, airway edema, dysphagia, cough, SOB, cardiac complications (heart valve damage, dysrhythmias, hardening of arteries), pulmonary damage (pneumonitis, chest pain, blood-tinged sputum), GI toxicity
  • Breast radiation therapy: breast soreness, lymphedema, cardiac complications, pulmonary damage, brachial plexopathy (damage to nerves of shoulder and arms that leads to numbness, tingling, pain, and weakness).
  • Pelvic radiation therapy (including prostate cancer therapy): blood in urine, difficulty urinating, frequent urination, incontinence/leakage, fertility issues, fistulas, rectal bleeding, diarrhea, cramping, vaginal dryness/narrowing/shortening, erectile dysfunction.

In addition, patients will often have radiation tattoos, which are small permanent dots on the skin that enable the radiation technician to aim the beam at the exact same location with every treatment.

A: How do you ASSESS a patient undergoing external beam radiation?

General assessments include taking vital signs and assessing pain level before and after treatment. You’ll also perform targeted assessments based on what signs/symptoms you expect to see based on the location of radiation. For example, if your patient is undergoing radiation on the neck, you’d assess for dysphagia, dry mouth, airway edema, etc…

Since radiation can cause leukopenia, assess the patient for signs of infection. Note that the patient may not be able to create more WBCs so other signs include fever, malaise, decreased LOC, and system-specific symptoms such as cloudy urine (UTI) or abnormal lung sounds (pneumonia).

Assess the patient’s fatigue level and ability to perform ADLs.

Weigh the patient and inquire about eating habits, appetite, and anything that may cause decreased intake such as nausea, mucositis or dysphagia.

Carefully assess the patient’s skin in the target area as it is likely to be a source of considerable discomfort for the patient.

Perform a psychosocial assessment, making note of the patient’s mood, anxiety level, coping mechanisms, response to treatment, support system and knowledge of the treatment plan/diagnosis.

T: What TESTS will be ordered?

The patient will receive some kind of imaging study to plan their radiation therapy, pinpoint the location and monitor the effects of therapy. This may include X-ray, CT scan, MRI and/or PET scan and often initially takes plus during the simulation appointment and again throughout or after therapy.

Lab tests will be performed specific to the patient’s type of cancer (when applicable, such as PSA for prostate cancer), and also include regular CBC tests to monitor for decreased blood counts and bone marrow suppression.

T: What TREATMENTS are provided?

Treatments for patients undergoing external beam radiation are going to be aimed at addressing symptoms and adverse effects. 

A lot of your interventions will be aimed at treating the skin which can be pretty severely affected by radiation therapy. Some key things to remember about treating radiation dermatitis are: 

  • Cleanse skin with mild soap and lukewarm water
  • Apply moisturizing cream and medicated creams as directed. Some common ones you may see used are:
    • Topical corticosteroids
    • Topical 1% atorvastatin
    • Silver sulfadiazine 
    • Silicone-based creams
  • Avoid the use of heating pads and ice
  • Use paper tape to secure any bandages, if used. 

Other treatments include addressing common signs/symptoms:

  • PRN medications to treat nausea (ex: ondansetron), diarrhea (ex: loperamide) or constipation (ex: docusate sodium).
  • Pain medications include acetaminophen, NSAIDs and opioids.
  • Mucositis may be treated with topical anesthetics – A commonly used medication is “magic mouthwash” which is a mixture of lidocaine, Maalox, and diphenhydramine. Other treatments for mucositis include anti-inflammatory drugs (ex: prednisone) and acetaminophen or even narcotics for pain. Assist patients with oral care and use either a soft bristle toothbrush or tooth sponges. Provide non-acidic, soft food options such as plain pasta, mashed potatoes, yogurt, protein shakes, eggs, and rice.
  • Encourage small, frequent meals that are high in protein to help prevent weight loss, and encourage fluids to prevent dehydration. 
  • Patients with decreased PO Intake may need enteral nutrition and IV fluids.

E: How do you EDUCATE the patient/family?

  • Individuals receiving external beam radiation are not radioactive and do not need to follow radiation precautions in the hospital or at home.
  • Ensure your patient understands how to take care of radiation dermatitis. In addition to the interventions discussed above, teach your patient to wear soft and loose clothing, avoid rubbing or scratching irritated areas, use electric shavers to remove hair if needed, avoid scented skin products and those containing lanolin, avoid exposing the area to sunlight, use deodorant only on intact skin, and using cool humidification can help with dryness.
  • Teach patients about the importance of eating enough protein and calories to maintain their weight. Protein shakes are a great option.
  • Teach the patient how to perform oral care and manage mucositis if receiving head/neck radiation. In addition to the interventions discussed above, teach the patient to avoid very hot and very cold foods, smoking, chewing tobacco and alcohol. Teach the patient to use an alcohol-free mouthwash and that sugar free candy or gum can help keep the mouth moist. A great tip to share is to moisten food with gravy or sauce. Foods that are well-tolerated include applesauce, oatmeal, pudding, eggs, and mashed potatoes.
  • Teach patients strategies to manage fatigue which include gentle exercise (such as walking) when feeling energetic, resting before periods of activity, and being willing to ask for help from family and friends when needed.

Review radiation therapy again while you’re on the go in episode 270 of the Straight A Nursing podcast. Tune in wherever you get your podcast fix, or straight from the website here.

The information, including but not limited to, audio, video, text, and graphics contained on this website are for educational purposes only. No content on this website is intended to guide nursing practice and does not supersede any individual healthcare provider’s scope of practice or any nursing school curriculum. Additionally, no content on this website is intended to be a substitute for professional medical advice, diagnosis or treatment.



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