Side effects of radiotherapy for lung cancer

High-energy radiation damages normal cells while destroying or eliminating cancer cells, which is the side effect of radiotherapy. The side effects caused by radiotherapy are usually divided into two types, acute and chronic. Acute side effects will occur soon after treatment and usually disappear completely within a few weeks after treatment stops; chronic side effects may take months or years to gradually appear, but are usually permanent.

Systemic reactions

It manifests as a series of functional disorders such as mental retardation, loss of appetite, physical weakness, fatigue, nausea, vomiting, and fullness after meals. Mild cases may not be treated, but severe cases should be treated in time and combined with Chinese medicine treatment to improve the body's immunity. Communication. Such as high-concentration Ganoderma lucidum preparations, fungal polysaccharide extracts, etc.

Local reactions

Dry skin is characterized by itching, hyperpigmentation and flaking, which can produce permanent light brown spots. Oily skin is characterized by eczema and blisters in the irradiated areas, and in severe cases can cause corrosion and ulcers.

Mucosal reactions

Mild: Symptoms include redness, erythema, congestion, decreased secretions of the oral mucosa, dry mouth, slight pain, and eating less.

Moderate: Oropharyngeal area is obviously congested and edematous, with punctate proteinogen, ulcer formation, obvious pain, and difficulty eating.

Severe: oral mucosal congestion, erosion, bleeding, fusion into protein, worsening ulcers, purulent secretions, severe pain, inability to eat, and occasional fever.

Radiation esophagitis

Acute radiation esophagitis is caused by radiation damage to the esophageal mucosa, decreased esophageal barrier protection function and inflammation. Clinical manifestations include dysphagia. Generally speaking, the absorption of tumor tissue reaches about 30Gy 2 to 3 weeks after the start of radiotherapy, reaches a peak at 4 to 5 weeks, and then can be alleviated until about 2 weeks after the end of radiotherapy. The incidence of acute radiation esophagitis varies greatly among individuals. In general, the incidence of severe acute radiation esophagitis in Asians is lower than that in Europeans and Americans. The combined use of chemotherapy and diabetes can increase the incidence of acute radiation esophagitis. Late damage is esophageal ulcers and esophageal stenosis. Traditional external beam radiation fractionated doses usually do not cause esophageal stenosis, but high-dose fractionated radiotherapy and intracavitary brachytherapy can cause this complication, which can be treated with dilatation stenosis or stents.

Radiation pneumonitis

Acute radiation pneumonitis is a common and dangerous complication in the treatment of lung cancer. In fact, permanent damage will occur to the lungs after 2000cGy irradiation. Acute exudative inflammation will occur in the irradiated lungs after 3000-4000cGy/3-4 weeks. Pathological examination shows thickening of the blood vessel wall, swelling of endothelial cells, formation of fibrous embolism, edema of the alveolar septa, and swelling of collagen fibers. This change occurs in every lung cancer patient exposed to radiation, but most patients do not develop symptoms. If the infection occurs at this time, the symptom is called acute radiation pneumonitis. If there are no symptoms, the inflammation gradually absorbs and dissipates after irradiation, and gradually forms varying degrees of vascular sclerosis and lung parenchymal fibrosis. Pulmonary fibrosis occurs about 6 months after irradiation and gradually worsens, reaching the most severe level at 1 year. The formation of radiation pneumonitis is most related to the irradiation area, dose and grading. The occurrence of radiation pneumonitis is also related to physical factors, individual differences and chronic lung disease. Improper use of anticancer drugs in combination with radiotherapy can promote the occurrence of radiation pneumonitis. The symptoms and signs of acute radiation pneumonitis are not special to general pneumonia, such as cough, sputum, fever, chest pain, shortness of breath, etc. The sound can be found through physical examination, but the number and severity of symptoms vary. The diagnosis of acute radiation pneumonitis is not difficult. It usually occurs shortly after the end of radiotherapy, with inducements such as upper sensation; there are symptoms and signs of pneumonia; it is important that the X-ray shows that the pneumonia is not clear, and it is best to confirm it with a chest X-ray. Acute radiation pneumonitis is mainly treated with antibiotics, corticosteroids, bronchodilators, etc., and symptomatic treatment such as oxygen when necessary. The dose of corticosteroids should be appropriately and slowly reduced, and should be used continuously for several weeks. The late stage is pulmonary fibrosis. When the irradiated area of ​​patients with poor lung function is large, lung function will deteriorate.

Radiation myelopathy

Radiation myelopathy should be strictly prevented during radiotherapy for lung cancer. It is important to design and implement a treatment plan to ensure that the spinal cord dose does not exceed its tolerable dose, which is no more than 4500 cGy within a 10 cm length.

Systemic reactions

It manifests as a series of functional disorders and imbalances, such as lack of energy, loss of appetite, physical weakness, fatigue, nausea, vomiting, bloating after eating, etc. Mild cases can be left untreated, while severe cases should be treated in a timely manner, combined with traditional Chinese medicine to improve the body's immunity, such as high-concentration Ganoderma lucidum preparations, fungal polysaccharide extracts, etc.

Local reactions

Dry skin can cause itching, pigmentation and peeling, which can produce permanent light brown spots. Oily skin can cause eczema and blisters on the irradiated area, and in severe cases, it can cause erosion and ulceration.

Mucosal reactions

Mild: Symptoms include redness, swelling, erythema, congestion of the oral mucosa, decreased secretions, dry mouth, slight pain, and slightly reduced food intake.

Moderate: Oropharyngeal area is obviously congested and edematous, with spotted white film and ulcers, obvious pain, and difficulty eating.

Severe: The oral mucosa is extremely congested, eroded, and bleeding, fused into a white membrane, the ulcers worsen, and there is purulent secretion, severe pain, inability to eat, and occasional fever.

Radiation esophagitis

Acute radiation esophagitis is caused by radiation-induced damage to the esophageal mucosa, decreased barrier protection function of the esophagus, and inflammation. The clinical manifestations are swallowing pain, which usually begins 2 to 3 weeks after the start of radiotherapy. The tumor tissue absorbs about 30Gy and reaches a peak at about 4 to 5 weeks. It may then be alleviated and last until about two weeks after the end of radiotherapy. The occurrence of acute radiation esophagitis varies greatly from person to person. Generally, the incidence of severe acute radiation esophagitis in Asians is lower than that in Europeans and Americans. The incidence of acute radiation esophagitis will increase in combination with chemotherapy, diabetes, etc. Late damage is esophageal ulcers and esophageal stenosis. Conventional fractionated dose external beam radiotherapy generally does not cause esophageal stenosis, but high-dose fractionated radiotherapy and intracavitary brachytherapy will cause this complication, which can be treated by dilation of the stenosis or stenting.

Radiation pneumonitis

Acute radiation pneumonitis is a common and dangerous complication of radiotherapy for lung cancer. In fact, permanent damage will occur after 2000cGy of lung irradiation, and acute exudative inflammation will occur after 3000-4000cGy/3-4 weeks of irradiation. Pathological examination shows thickening of blood vessel walls, swelling of endothelial cells, formation of fibrous emboli, edema of alveolar septa, and swelling of collagen fibers. This change occurs in every irradiated lung cancer patient, but most of them do not produce symptoms. If there is an infection at this time, symptoms will occur, which is called acute radiation pneumonitis. If no symptoms occur, after the irradiation is over, the inflammation will gradually absorb and dissipate, and gradually form progressive vascular sclerosis and fibrosis of the lung parenchyma to varying degrees. Pulmonary fibrosis occurs about 6 months after irradiation, gradually worsens, and reaches the most serious level in 1 year. The formation of radiation pneumonitis is most related to the irradiated area, and is also related to dose and fractionation. Body factors, individual differences, and the presence or absence of chronic lung disease are also related to the occurrence of radiation pneumonitis. Improper combined use of anticancer drugs in radiotherapy can promote the occurrence of radiation pneumonitis. The symptoms and signs of acute radiation pneumonitis are no different from those of general pneumonia, such as cough, sputum, fever, chest pain, shortness of breath, etc. Pharyngitis can be detected during physical examination, but the number and severity of symptoms vary. The diagnosis of acute radiation pneumonitis is not difficult. It usually occurs shortly after the end of radiotherapy, with inducements, such as upper respiratory tract infection, etc.; there are symptoms and signs of pneumonia; it is important that the X-ray shows that pneumonia is not clear on the fluoroscopy, and it is best to take a chest X-ray to confirm. Acute radiation pneumonitis is mainly treated with antibiotics, corticosteroids, bronchodilators, etc., and symptomatic treatment such as oxygen can be given when necessary. The dosage of corticosteroids should be sufficient, slowly reduced, and used continuously for several weeks. Late stage manifestations include pulmonary fibrosis. When the irradiated area is large, the lung function of patients with poor lung function will be worse.

Radiation myelopathy

The occurrence of radiation myelopathy should be strictly prevented during radiotherapy for lung cancer. It is important to ensure that the spinal cord does not exceed its tolerance dose when designing and implementing the treatment plan, that is, no more than 4500 cGy within a 10 cm length.

Cardiac damage is less common, mostly pericarditis. When irradiated with 4281cGy, the incidence of cardiac complications was 6.6%. Chemotherapy can increase the incidence of cardiac complications, such as the use of doxorubicin.