Page 40 Complete Your CE Test Online - Click Here ● ● Accelerated fractionation, which gives the half of the usual daily dose of radiation twice each day. ● ● Hyperfractionation, which is a smaller than usual daily dose of radiation given twice each day. ● ● Hypofractionation, which is a larger than usual daily dose of radiation given once a day for up to three weeks. Teach patients to avoid removal of radiation markings until after treatment, or let them know if the mark is tattooed and permanent. Patients will need to cover irradiated skin to protect from sunlight for at least a year after treatment. If the site cannot be covered and sun exposure is unavoidable, they can try a gentle, fragrance-free broad-spectrum sunscreen of 30 SPF or higher. Teach the patient to clean irritated skin very gently with mild soaps, avoid shaving if possible, and to use an electric razor if they must, and to protect the site from rubbing, pressure or irritation by wearing loose, soft fabrics next to the skin. Avoid alcohol-containing liquids, aftershave lotions, powders, depilatories, deodorants, tape, and extreme heat or cold to the area [57]. If skin becomes dry, most treatment centers recommend twice-daily use of moisturizing creams without fragrances, such as Aquaphor, Cetaphil, Eucerin, Vanicream, and Cerave, which are available over the counter at drugstores [129,222]. Radiation therapy can cause acute and chronic side effects, a lot of which depend on the body part being irradiated and the radiation dose. Common acute side effects of radiation, regardless of site, are fatigue and nausea. Depending on the site, the patient may also have: ● ● Erythematous or pruritic, tender, dry, or weeping skin at the radiation port. ● ● Alopecia at the treatment site, which can become permanent. ● ● Dry mouth, dysphagia (difficulty swallowing), odynophagia (painful swallowing), mucositis, dysgeusia (taste changes) from head and neck radiation. ● ● Dysphagia, cough, dyspnea from chest radiation. ● ● Nausea, vomiting, diarrhea from abdominal radiation. ● ● Diarrhea, cystitis, urinary frequency, sexual dysfunction from pelvic radiation. Most of the acute effects end soon after the radiation course is completed [124,188]. Talk with the patient about when to call the office or treatment center, including contact information for the oncologist on nights and weekends, such as when experiencing [129]: ● ● Fever of 100.5 degrees Fahrenheit (°F) or above. ● ● Pain. ● ● Swelling. ● ● Vomiting or severe diarrhea. ● ● Blistering, drainage, rash, or skin breakdown in the treated area. ● ● Any new symptoms. Some kinds of acute damage can become permanent, such as salivary gland damage. The drug amifostine can help protect the salivary glands if given during radiation treatment. Although research is being done on other ways to protect normal tissues from radiation damage, this is the only drug approved for it as of early 2016 [188]. Late effects, which can occur months or years later, depend on the area of the body treated by radiation. These chronic effects can include: ● ● Skin darkening, scarring, and fibrosis, which can cause restricted movement. ● ● Bowel damage which can cause diarrhea and bleeding after abdominal treatment. ● ● Memory loss and cognitive changes after brain radiation. ● ● Infertility after pelvic radiation. ● ● Second cancers. Keep in mind that second cancers are more common in people who were treated as children or adolescents [189]. There are other ways to deliver external radiation that use special techniques intended to focus more tightly on the tumor and reduce the damage to normal tissues nearby: ● ● 3-dimensional conformal radiation therapy (3D CRT) uses a regular linac to generate and aim the radiation, and also uses an imaging scan with computer mapping to precisely pinpoint tumor location 3-dimensionally and allow a tighter aim of radiation beams. ● ● Intensity-modulated radiation therapy (IMRT) uses conformal techniques like 3D CRT, but also allows different strengths of beams to be sent to different areas. ● ● Image-guided radiation therapy (IGRT) has scanners built into the linear accelerator machine, so that images of the tumor can be checked before each treatment. This may be more important when a tumor is shrinking or changing shape during the course of treatment, as it lets the doctor tweak the radiation area so that less normal tissue is hit. ● ● Stereotactic radiosurgery (SRS) use imaging to give a large dose of radiation to a small tumor in one session, from a number of different angles. Despite the name, no actual surgery is involved. There are a number of machines that do this, like the Gamma Knife, X-Knife, CyberKnife, or Clinac; some deliver the radiation all in one burst while others move around to deliver it from one direction to another but still in one session. These are often used for brain tumors but can be used for small tumors in other parts of the body. ● ● Fractionated stereotactic radiotherapy (FSRT) is very much like SRS, above, but the radiation is spread out over several doses. Of note, there are other types of external radiation than the typical photon beams from a linac. Some specialized cancer treatment centers use particle beams like proton beams, neutron beams, and carbon ions. Electron beams can also be produced by a linac, but they have low energy levels and do not penetrate deeply. These are used for skin or structures that are close to the body surface [40]. Internal radiation therapy Internal radiation therapy places a source of radiation inside the body. Radiopharmaceuticals can be taken or injected in liquid form for some types of cancer treatment. More commonly, the radiation source can be implanted (brachytherapy) right into and around the tumor (interstitially) or placed in a body cavity (intracavitary) [7]. Radiopharmaceuticals: In systemic internal radiation therapy, the patient swallows or is given an injection of a radioactive substance, such as radioactive iodine or a radioactive substance bound to a monoclonal antibody. Radioactive iodine (131I) for example, is commonly used to help treat some types of thyroid cancer. Thyroid cells naturally take up radioactive iodine [189]. For systemic radiation therapy for other types of cancer, a monoclonal antibody helps the radioisotope bind to the right cells. The antibody is attached to the radioactive substance, and delivers the radiation directly to tumor cells. For example [189]: ● ● The drug ibritumomab tiuxetan (Zevalin®) is used to treat certain types of B-cell non-Hodgkin lymphomas (NHL). The antibody part of the drug binds to a protein found on the surface of B lymphocytes. ● ● The combination drug regimen of tositumomab and iodine I 131 tositumomab (Bexxar®) is used to treat certain types of NHL. The nonradioactive tositumomab antibodies are given to patients first, followed by treatment with tositumomab antibodies that have 131I attached. Tositumomab binds to the same protein on B lymphocytes as ibritumomab. Other systemic radiation therapy drugs are in clinical trials for different cancer types. Some palliative systemic radiation therapy drugs already in use are used to help relieve pain from bone metastases. For example, the radioactive drugs samarium-153-