Answers to Common Questions about Radiation Safety

By Andrea Peirce

on Thursday, April 3, 2014

Pictured: Alice Ho
Summary

Memorial Sloan Kettering Radiation Safety Officer Jean St. Germain answers common questions about the safety of adults undergoing radiation treatment for cancer.

Radiation treatment is one of the most common and effective ways to destroy cancer cells and shrink tumors. It works by exposing targeted areas to high-energy rays or waves in such a way that the structure of cells is damaged or destroyed.

At Memorial Sloan Kettering, approximately half of our adult cancer patients undergo radiation therapy as a form of primary treatment or as part of a broader approach that includes chemotherapy, surgery, or other modalities. For many cancers, radiation treatment may be all that is needed to eliminate disease.

There are different ways to deliver radiation treatment. With external beam radiation therapy, treatment is delivered from a machine outside the body. With internal radiation (brachytherapy), sealed sources of radioactivity are placed near or within the tumor. Less commonly, radiation treatment can also be administered using liquid materials by mouth or infusion through a vein (systemic radiation).

Although it has been a widely used treatment for decades, confusion and misunderstandings about the safety of radiation treatment persist. We asked Memorial Sloan Kettering Radiation Safety Officer Jean St. Germain to tell us about the concerns she hears most frequently from patients and their families — and what answers and reassurance she provides.

Does receiving external-beam radiation make a person radioactive or able to expose others to radiation?

External-beam therapy does not make a person radioactive in any way. The therapy only affects your cells for the very short time that you are receiving treatment. A person who has received external-beam radiation is unable to contaminate or transfer that radiation to any other person.

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How can I be sure that the external-beam radiation machine isn’t damaging normal, healthy tissue in my body?

We have carefully developed methods for calibrating radiation beams and ensuring that they reach the areas they are intended to target. Even when normal tissues near the area undergoing radiation receive small amounts of radiation, it is rare for long-term damage to occur. Our doctors also know how much radiation healthy tissue can receive without causing irreversible damage. We often use special masks, molds, or casts of body parts to keep you absolutely still during treatment, so that we can aim the radiation beams precisely to the area we want to treat.

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Is there any risk that internal radiation implants (brachytherapy) will leak or break free from where they are placed and move around my body?

With brachytherapy, we use a needle or a catheter to insert radioactive material contained within an impenetrable sealed source such as a seed, pellet, wire, or capsule. As the radioactive isotopes inside the implant decay naturally over time, they emit radiation and damage nearby cancer cells. This radioactivity travels only a certain distance beyond the implant, and eventually deteriorates to the point that the implant no longer gives off any radiation. The implants are specially tested and sealed to ensure that radioactive material doesn’t leak, and we place them in such a way that it’s highly unlikely they will move. Also, in the case of brachytherapy for genitourinary cancers, while there is no risk that the implants will come out with semen, we do give patients a strainer to use for 24 to 48 hours after the procedure when urinating, in the rare case that a seed becomes dislodged.

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Should I limit contact with anyone while brachytherapy implants are inside my body?

Most of our safety concerns are related to being in physical contact with children for extended periods of time, since their bodies are undergoing such rapid change and growth and are therefore more vulnerable to abnormal cell changes. Because we vary the radiation dose in each implant as well as the number of implants we insert based on your particular cancer, we provide you with specific advice about precautions to take when you’re in close contact with children.

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Do prostate seed implants put my sexual partner or the person I sleep next to at risk in any way?

Prostate seeds are sealed sources. You cannot contaminate another person by being in his or her physical vicinity, during sexual intercourse, or through any other form of intimate contact. Your doctor or a member of the radiation safety staff will discuss any special precautions you should take with sleep arrangements before you leave the hospital. For example, based on such factors as your age and the age of your partner, for a period of time we may ask that you avoid embracing your partner from the back in the “spooning“ position through the night.

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Do I pose a danger to others after receiving radioactive iodine therapy for thyroid cancer?

For several days following this therapy, radioactive substances can be emitted through body fluids such as saliva, urine, and sweat. We send patients home with detailed instructions on how to care for themselves for the first few days — from limiting contact with young children and pets to using separate utensils and towels.

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I am having an imaging test using radioactive materials. Will I be radioactive after the test?

Radioactive material will stay in your body for several hours or days depending on the type used and the metabolism of the compound to which it was attached. Eventually, the material decays and your body naturally flushes it out through urine, sweat, and other forms of biological elimination. We make sure the specifics are clear to you before the test, and we may also issue an information card explaining your treatment in the event that you are questioned by someone in airport security, for example.

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Comments

no one ever told me when I had radiation 8 years ago that I could develop an Angiosarcoma...So it's a big surprise that I now have a full blown sarcoma.

Following Brachytherapy and beam radiation is there a limit to the amount of radiation to a particular site?
If further cancer develops in the bone area already treated can further radiation be used to quell or kill the cancer?
What is the outcome of too much radiation to a bone or soft tissue site?
Are there further options in such circumstances?
Thanks for your help.

Roger, thanks for reaching out! There are no specific regulatory limits on the amount of radiation to a particular site during treatment when that treatment has been deemed appropriate and justified by your doctor. Our doctors follows appropriateness criteria and accepted professional guidance, along with best procedures based on the latest research to deliver appropriate treatments. They always seek to target the most effective dose of radiation directly at the cancer, while minimizing radiation to the healthy parts of a patient's body. Decisions about the best therapy and best technology are based on each individual case. Also, different tissues have a different sensitivity and response to various types of radiation. Each case is unique.

Unfortunately we can't answer personal medical questions on our blog. But if you or someone you care for has had radiation to the bone and you are wondering about treatment options, we encourage you to consult with one of our specialists. Please call our Physician Referral Service at 800-525-2225.

Radiation caused damages to chromosomes.Will long term Radiotherapy treatment cause permanent chromosomal damages leading to gene mutation?

I too am interested in the damage to chromosomes leading to gene mutation.
Since radiation three years ago I have developed MDS. Is there a possible link?

Thank you for writing, Carol! Unfortunately we cannot answer personal medical questions on our blog. If you would like to make an appointment for a consultation with one of our specialists who can provide a personalized assessment of your treatment options, please call our Physician Referral Service at 800-525-2225.

It is stated above, "it is rare for long term damage to occur." Are the studies available to confirm this? i.e. breast radiation - 10 years later, lung or respiratory damage?

Lana, we sent your question to Beryl McCormick, Chief of our External Beam Radiotherapy Service, who responded that there have been several studies of the long-term effects of breast radiation. Two of the largest were reported in the New England Journal of Medicine in 2002
(http://www.ncbi.nlm.nih.gov/pubmed/12393820) and in the Lancet Oncology in 2005 (http://www.ncbi.nlm.nih.gov/pubmed/16054566). She noted that this area has been studied with much longer follow-up than some of the newer chemotherapy regimens. Thank you for your comment.

Are there any allergic reactions caused by the radioactive material used during a CT scan or a PET scan such as Itching and a soft red rash?

Joe, radioactive materials are not used during regular CT scans, but they are used during PET scans and PET/CT scans. It's possible to have an allergic reaction to the tracer. If you think you have had an allergic reaction, we recommend that you discuss this with your doctor. Thank you for your comment.

Are you allowed to go swimming after radiation treatment

Eileen, radiation treatment can cause sensitivity of the skin, so this is something you should discuss with your doctor. Thank you for your comment.

As a caregiver, what precautionary safety measures do i take when one of my clients start radiation treatments for 7 weeks, 5 days a week?

External-beam therapy does not make a person radioactive in any way. The therapy only affects your cells for the very short time that you are receiving treatment. A person who has received external-beam radiation is unable to contaminate or transfer that radiation to any other person. Thank you for your comment.

I have had a full hysterectomy and was classified as stage one. Soon I will be receiving brachytherapy to my vaginal cuff. How long is the possible risk of radiation exposure to my young grandchildren and others? I don't want to be treated as a leper but also don't want to harm others in even the slightest way.

I have been diagnosed with breast cancer, and have a choice between mastectomy and lumpectomy with radiation. I also have extensive psoriasis, which has been kept under control for several years with short daily UVB-narrow spectrum radiation treatments. Would I be able to continue those treatments if I have radiation therapy for the cancer? Thank you for your answer.

This is something you should discuss with your dermatologist and your radiation oncologist. Thank you for your comment.

My husband had brachy therapy may 2015. June2015 I developed a topical dermatitis on my hands which I only managed to clear by December. I have now developed shingles on my face. The only changes was hisbrachy treatment. I'd it possible that my immune system has weakened from sleeping inthe same bed

Linda, thank you for reaching out. We passed your question on to MSK expert Laurence Dauer, who responds:

Several studies have been performed that have shown that the exposure to any family members from brachytherapy patients are well below any recommended precaution limits. As such, it is not at all likely that your immune system was weakened from sleeping in the same bed. The potential dose rates are simply much to small to have any effect.

I will soon be having a course of radiation after lumpectomy for DCIS. I also have Hashimoto's Thyroiditis and have been warned to avoid X-rays as much as possible (airports,dental) due to risk of thyroid cancer. I've been told no shield will be used on my thyroid which concerns me. Thank you.

Dear Karen, we are sorry to hear about your diagnosis. We encourage you to discuss any questions or concerns you may have with your physician. Thank you for your comment.

My husband had a 200 milicure (don't know if I spelled it correctly) dose of radioactive iodine 13 days ago...we just had oral sex for the first time since the treatment...I swallowed the semen. Will I be in any danger?

Linda, we recommend you discuss with your husband's healthcare team how long the radioactive iodine remains in the body after the treatment he had. Thank you for your comment.

I had a lumpectomy last week in January. I was advised to start radiation treatment 6-8 weeks after surgery. I have a family event coming up & would like to know if I postpone another 4 weeks do I put myself at an unnecessary risk? Please advise.

Thank you

Dear Marie, we are sorry to hear about your diagnosis. Unfortunately, we are not able to offer specific medical advice on our blog. Please follow up with your oncologist, who knows your full medical history and can provide a more informed recommendation for you. Thank you for reaching out to us.

Can a person that has stared radiation treatment in one city be transferred to another
The reason I ask is because my husband is like 2hours away and I can't get the equipment needed for home care of his trach

We recommend that you ask your husband's healthcare team what other options may be available for his treatment. Thank you for your comment.

I understand that EBRT focuses on the tumor or tumor site thus reducing harm to nearby healthy tissue. But what if it is being used as a preventive: If there is no evidence of disease and it is being used in case a microscopic cancer cell remained behind after surgery, then it is zapping healthy tissue. Will that lead to long term side effects?

Dear Lorraine, we sent your inquiry to medical physicist and radiation safety expert Jean St. Germain and she responded:

"The goal of modern techniques such as Intensity Modulated Radiation Therapy [IMRT] or Image Guided Radiation Therapy [IGRT] is to maximize the dose to the tumor while sparing as much normal tissue as possible. Neither of these techniques are used as a preventative. There must be a disease process present to prescribe radiation therapy. That disease process is usually a cancer, although there may be the rare circumstance in which radiation therapy is used on a serious, but non-cancerous, disease process such as an aterio-venous malformation [AVM]. The potential for cancer cells to escape during surgery or radiation treatment depends on the type of tumor, its location, and the profession's overall experience with the type of disease involved. Typically, chemotherapy, a systemic treatment, may be used in these cases."

We hope this information is helpful. Thank you for reaching out to us.

Yesterday I took 9 small dose pills of 1-123 iodine radiation for a full body scan last month I had almost all of my thyroid removed for papillary cancer I have a 1/4 of my thyroid left cause of the location of a mass and the one nerve left for my voice box still attached with no damage the doctor wants to see if we can kill the rest of the cancer with radiation but the pet scan showed up 2 spots in my lungs so that's why I got a full body scan today but curious how long I have to stay away from my very young great nieces and nephews being I'm a important part of their lives!

Frank, this is something you should discuss with your doctors. Thank you for your comment.

My 20 year old daughter received radioactive iodine treatment for her thyroid cancer (small tumor) on Tursday. My 16 year old son wants to go see her for a little while which I'm not sure is a good idea just yet and haven't decided to let him do so. If he does what is the risk to him and is there a risk that he can pass along any radioactive material to his younger brother and sister?

Eric, we sent your question to Jean St. Germain, who replied, "Radioiodine (I-131) is used for treatment of thyroid tumors because the thyroid concentrates the iodine. Approximately 50% of the administered dose is excreted within 24 hours, primarily in urine, but also in sweat and saliva with a small amount in feces. The biological excretion continues in smaller amounts, and eventually, all iodine remaining in the body is concentrated in the thyroid itself. After approximately 72 hours, there is little biological elimination. As long as your son does not contact bodily fluids, the chief problem would be exposure from the iodine in her thyroid. It would usually be recommended that visitors remain at a distance of approximately 1 meter (about 3 ft.) for a period of about 1 week. Since these statements are in general, you may wish to consult with the authorized nuclear medicine physician who administered the therapy." Thank you for your comment.

Just went threw 42 radiation and 6 chemo had tonsils uvula esophagus and lymphoids cancer feeding tube and port now thyroid fried anyone have input

In regard to lung cancer resulting from radiation therapy treatment for breast cancer, I read in an article from cancergrace stating that data from the United States and Sweden indicates that patients treated before the mid 1980’s were noted to have approximately a 0.5% increase in the risk of developing lung cancer – almost all secondary lung cancers appear to be in smokers. However, among patients treated in the last 30 years, this increased risk of lung cancer has disappeared. In your experience, would you say that this is true?

Mamie, thank you for your question. We consulted with MSK radiation oncologists, who state that "Techniques have improved dramatically since the 1980’s, but it will take at least 15 years after treatment refinements have been routine to detect the impact on long term consequences of radiation, of which secondary cancers are one."

I have heard that after having radiation seeds to treat cancer the affected area can eventually adhere to other nearby organs, thus making those organs inoperable. Can surgery still be done on other parts of the body not affected by the seeds?

Dear Ralph, we forwarded your inquiry to Dr. Michael Zelefsky, Chief of MSK's Brachytherapy Service. He responded:

"With modern day radiation techniques, the likelihood that radiation seeds cause scarring to the effect that the prostate adheres to other organs would be extremely unusual. Radiation of course can cause some scarring on the sphincter muscles making subsequent prostate surgery riskier for incontinence of urine. After prostate radiation, surgery can still be done on other parts of the body in general without difficulty."

We hope this is helpful. Thank you for reaching out to us.

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