When it comes to radiation therapy, many people think of side effects first. However, radiation therapy is considered one of the three major cancer treatments along with surgery and chemotherapy. Therefore, it is recognized as an important treatment that is indispensable for curing cancer. Recently, it is being used to treat benign diseases such as keloids (post-wound scars), meningiomas, and ventricular tachycardia, as well as malignant tumors, expanding its therapeutic area.
Radiation therapy refers to obtaining a therapeutic effect by accurately irradiating the planned radiation dose to the tumor. It is largely divided into ‘curative radiation therapy’ for the purpose of cure, ‘adjuvant radiation therapy’ to enhance the treatment effect before and after surgery, and ‘palliative radiation therapy’ for symptom relief.
Radiation therapy is generally performed once a day, 5 times a week, from Monday to Friday. The treatment time is usually 5 to 10 minutes, but it may take more time in the case of special treatment. Treatment is similar to computed tomography (CT). Move the machine while the patient is lying down to treat. There is no pain felt during treatment. The duration of treatment depends on the purpose. For the purpose of complete cure, it takes 6-8 weeks, adjuvant treatment takes 5-6 weeks, and palliative treatment takes 2-3 weeks.
Professor Kim Myung-soo of the Department of Radiation Oncology, Catholic University of Korea Incheon St. Mary’s Hospital, said, “Radiation therapy causes chemical denaturation of nucleic acids and cell membranes, which are substances essential for cell proliferation and survival, when irradiating the body with radiation. It is a principle that effectively treats cancer cells,” he said. With the help of Professor Myung-soo Kim, we will learn about the side effects of radiation therapy and how to deal with it.
Breast Cancer- Changes in the skin at the treatment site
Radiation pneumonia can occur as a chronic side effect after radiation therapy. Radiation therapy after complete mastectomy is more likely to occur than radiation therapy after breast-conserving surgery (partial mastectomy). Radiation pneumonia usually develops within about 3 months immediately after radiation therapy. Symptoms are accompanied by mild fever, mild cough, and phlegm, and usually last for 1 to 2 weeks and then resolve spontaneously without any complications. During radiation therapy, chest X-rays are performed every 2 weeks.
The primary treatment for breast cancer is surgical removal. After surgery, adjuvant radiation therapy, chemotherapy, and hormone therapy can be administered. Radiation therapy is required for all patients who have undergone breast-conserving surgery for breast cancer to prevent recurrence because micro-tumor cells may remain in the surrounding tissue. After 5 to 6 weeks of radiation therapy to the entire breast on the operated side, intensive irradiation is performed for 1 to 2 weeks in the area where the tumor was located. In early-stage breast cancer, low-fraction radiation therapy, which treats less than 20 treatments, is also widely used. Even after complete mastectomy, adjuvant radiotherapy is required depending on the surgical outcome, such as the size of the tumor and the number of lymph nodes involved. In addition, if there is a local recurrence in the chest wall or lymph node, or if there are symptoms due to metastasis to the bone or brain, radiation therapy is performed.
Professor Kim Myung-soo of the Department of Radiation Oncology at Incheon St. Mary’s Hospital said, “The skin in the breast area that has been treated with radiation has enlarged sweat pores and becomes more sensitive and sometimes dull. It may feel hard and you may feel a change in size, but it gets better with time.”
Lung Cancer- Weekly chest x-ray to confirm radiation pneumonitis progress
Lung cancer is largely divided into non-small cell lung cancer and small cell lung cancer according to the shape of the cells. For non-small cell lung cancer, surgical removal is performed when it is detected at an early stage, and radiation therapy and chemotherapy are performed simultaneously for stage 3 or higher where surgical resection is not possible. Except for the initial postoperative period, chemotherapy should be combined with radiation therapy and chemotherapy, especially if there are risk factors for recurrence.
In some cases, surgery is performed after chemotherapy and radiation therapy. For non-small cell lung cancer with metastases, chemotherapy is the main treatment, and when symptoms are local, radiation therapy can be performed to relieve symptoms. For advanced lung cancer without surgery, radiation therapy is usually performed for 6-7 weeks, and radiation therapy after surgery takes about 6 weeks. For small cell lung cancer, radiation therapy and chemotherapy are mainly used in combination, and radiation therapy takes 6-7 weeks.
A common side effect of chest radiotherapy is esophagitis. After treatment, radiation pneumonitis and pulmonary fibrosis may occur. Esophagitis occurs when the irradiated area contains the esophagus, and 2 to 3 weeks after the start of treatment, you may experience difficulty swallowing, starting with a feeling as if something is stuck in your throat. If symptoms of esophagitis appear, administer medication to relieve symptoms, and in rare but severe cases, a tube is inserted into the stomach and food is administered and treatment is terminated. Radiation pneumonia usually develops within about 3 months immediately after radiation therapy. Professor Kim Myung-soo said, “The symptoms of radiation pneumonia are accompanied by shortness of breath, low fever, mild cough, and phlegm, and usually heals naturally without any complications after 1 to 2 weeks, but in rare cases hospitalization is required.” “Radiation therapy During the period, chest radiographs should be performed every week to check the progress of radiation pneumonitis.”
Colorectal cancer- Beware of possible infection in the rectal area
Radiation therapy for rectal cancer is performed adjuvantly before or after surgery for advanced rectal cancer. The scope of treatment is the anterior pelvis, including the rectum and surrounding pelvic lymph nodes. Recently, when rectal cancer is near the anus, preoperative radiation therapy is sometimes performed to increase the preservation rate of the anus and to facilitate surgical removal of advanced rectal cancer. Treatment consists of external radiation therapy for 5 to 6 weeks for the anterior pelvis. If the scope of radiation therapy includes the small intestine, large intestine, and rectum, you may experience diarrhea (or loose stools), abdominal cramps, and rectal discomfort.
Diarrhea due to radiation therapy may appear about 2 weeks after starting treatment. When you receive radiation therapy, the skin around the anus becomes sensitive, which makes it easy to get wounds. In this case, not only the pain is severe, but there is also the possibility of infection. Reproductive function may be affected if the ovaries or testicles are included in the scope of radiation therapy. This can cause temporary or permanent infertility. If you want to become pregnant, you must consult your doctor before treatment.
Prostate cancer- Accurate investigation of the small prostate area is key
Prostate cancer is the fourth most common cancer among men in Korea after lung cancer, stomach cancer, and colorectal cancer. Although it is accompanied by symptoms such as dysuria or dysuria, it is difficult to distinguish it from the symptoms of benign prostatic hyperplasia, which is common in old age, so it is detected through PSA (Prostate Specific Antigen) in most screening tests.
Prostate cancer can be cured with surgery or radiation therapy if detected early. Radiation therapy can also be administered to patients at high risk of recurrence after surgery or patients with elevated PSA levels. For advanced prostate cancer, which is difficult to operate, hormone therapy and radiation therapy are the international standard treatments. It usually takes 6-8 weeks. If there is metastasis to the lower pelvic region or lymph nodes with prostate cancer, or if there is a high risk of recurrence, treatment should include the pelvic lymph nodes. The most important thing in radiation therapy for prostate cancer is whether radiation can be accurately irradiated to the small prostate area. Recently, radiation therapy that minimizes the amount of radiation applied to surrounding normal tissues, such as intensity-controlled radiation therapy and image-guided radiation therapy, has been introduced, reducing side effects and maximizing the therapeutic effect.
Side effects may include diarrhea and, in severe cases, rectal bleeding due to inflammation of the rectum and anus. However, as technologies such as intensity-controlled radiation therapy and image-guided radiation therapy have been developed recently, the possibility of side effects is gradually decreasing. Cystitis symptoms such as dysuria or frequent urination may also occur. Side effects such as erectile dysfunction and urinary incontinence that may appear with surgery are less common with radiation therapy. Usually, these symptoms appear from 2 to 3 weeks after the start of treatment and resolve spontaneously within 2 to 4 weeks after treatment.
Prostate cancer mainly occurred in the elderly, but recently, the number of prostate cancer patients in middle-aged people is increasing. Professor Kim Myung-soo said, “The incidence of prostate cancer is increasing among middle-aged Koreans due to a westernized diet that consumes a lot of meat.
Head and Neck Cancer – Temporary dry mouth and voice changes
Radiation therapy for head and neck cancer is largely divided into curative radiation therapy, which aims to cure, and adjuvant radiation therapy, which is administered as an adjuvant after surgery. Curative radiation therapy is performed for most head and neck cancers without surgery. Among these, nasopharyngeal cancer is difficult to access surgically and has a good response to radiation therapy, so curative radiation therapy has been traditionally performed. For advanced nasopharyngeal cancer, it is used in combination with chemotherapy to increase the therapeutic effect. Early glottal cancer (cancer of the vocal cords) has a very high chance of being cured with only radiation therapy.
In addition, surgery or radical radiation therapy can be performed for laryngeal cancer, oral cancer, pharyngeal cancer, hypopharyngeal cancer, salivary gland cancer, and sinus cancer depending on the stage and patient’s condition. Adjuvant radiotherapy is administered if there are risk factors for recurrence even after surgery. The duration is 7-8 weeks for radical radiation therapy and 6-7 weeks for postoperative radiation therapy. Professor Kim Myung-soo explained, “In the past, radiation therapy for head and neck cancer had many side effects, but recently, through intensity-controlled radiation therapy, it has been possible to reduce side effects by focusing radiation irradiation only on the treated area and minimizing radiation to surrounding normal organs.” did.
When the salivary glands are destroyed due to radiation therapy, the secretion of saliva decreases and as a result, dry mouth occurs. The detailed symptoms may include difficulty swallowing food due to pain in the mouth, changes in taste, pain and inflammation in the ears, limited or swelling of the mandibular joint, and changes in voice. These symptoms start around 2-3 weeks after the start of radiation therapy and disappear 2-4 weeks after the end of treatment.