Chemotherapy side effects are a complex of negative reactions and diseases that occur at different times during the course of taking cytostatics and after completion of treatment. The list of side effects is extensive: from dyspeptic disorders and mucositis to septic conditions and severe immunodeficiency. To monitor the condition of patients during chemotherapy, regular blood and urine tests, ultrasound, radiography and other instrumental imaging methods are carried out. When complications occur, the treatment protocol is changed or symptomatic medications are prescribed to improve well-being.
ICD 10
T88.8 Other specified complications of surgical and therapeutic interventions, not classified elsewhere
Meaning
At least one chemotherapy side effects is observed in every patient who undergoes drug treatment for oncopathology. Since there are more than 3.7 million people with cancer in the United States, and most of them receive cytostatics, iatrogenic complications pose a serious problem for practical oncology. The consequences of chemotherapy significantly worsen the lives of patients and can cause death, therefore they require careful attention and an individual therapy program.
Causes
By itself, the appointment of chemotherapy is a risk factor for complications. The nature and intensity of adverse reactions varies depending on the selected pharmacological group of cytostatics. For each category of drugs, there are typical negative consequences that the patient is informed about before prescribing antitumor therapy. Other factors also affect the likelihood of developing chemotherapy side effects:
- Somatic status of the patient. Prognostically unfavorable factors include an age of more than 60 years and an ECOG score of more than 2 points, which corresponds to a limitation of the patient’s working capacity and mobility. If there were chronic diseases before the start of treatment, they progress against the background of chemotherapy and turn into a severe form.
- Stage of oncopathology. Patients with 1-2 stages of cancer who are in good health and do not suffer from significant systemic manifestations of the tumor, better tolerate cytostatic therapy. Advanced stages are associated with serious health disorders that create an unfavorable background for chemotherapy side effects.
- The scheme of chemotherapy. A higher risk of adverse reactions occurs with a polychemotherapy regimen with a combination of 2-3 drugs having different mechanisms of action. They quickly depress the immune system and have a direct toxic effect on healthy cells of various organs and systems.
- The state of the immune system. With all types of oncopathology, there is an inhibition of immunity, but people who suffered from immunodeficiency before the development of the tumor are at particular risk. This includes HIV-infected people who do not receive VAART, patients with congenital syndromes (Di Giorgi, Viscotta-Aldrich, Louis-Bar, TKID).
Pathogenesis
Cytostatics, which are used in oncopathology, have antiproliferative activity. They act at different stages of cell division, but have the same effect – they suppress the reproduction of malignant cells. Since the cytostatic effect is not specific, it also affects healthy tissues. The target of cytostatics are rapidly dividing cells, which include the precursors of hematopoiesis, the epithelium of the gastrointestinal tract and hair follicles.
The toxicity of drugs is a key, but not the only mechanism for the appearance of chemotherapy side effects. Drug-induced health impairments develop against the background of allergic reactions and intolerance to a particular drug. Local inflammatory and necrotic processes are also possible in the area of injection or dropper placement. Often, one patient has several mechanisms.
Classification
According to the time of occurrence, chemotherapy side effects are divided into immediate, which appear within 1-2 days after administration of the drug, the nearest (in the middle of the course of treatment) and later (1.5-2 months or more after the therapeutic course). A special group includes long-term consequences that manifest themselves several years after the completion of treatment. Clinical classification is also widely used in oncological practice:
1. Toxic effect of drugs. The most numerous group of complications of oncotherapy, which in varying degrees of severity occurs in all patients. Complications are divided into 2 categories:
- Local. Caused by the toxic effect of the drug at the site of its administration. They include toxic dermatitis, inflammatory infiltrates, and inflammation of the veins (phlebitis). When drugs are injected into the body cavity, the development of aseptic serositis is possible.
- System. This group includes inhibition of hematopoiesis (febrile neutropenia, agranulocytosis, pancytopenia), dyspeptic syndrome, skin and mucous membrane lesions. Cardiotoxic, nephrotoxic, hepatotoxic effects are common. Lesions of the reproductive system are characteristic.
2. Immune disorders. The key link is persistent immunosuppression, against which opportunistic and other types of infections develop. Autoimmune reactions of the type of hemolytic anemia and vasculitis are possible.
3. Intolerance to drugs. This type of complications is quite rare and is associated with idiosyncrasy to the drug used. The condition is manifested by unpredictable reactions even to low doses of cytostatics, paradoxical effect of drugs.
4. Negative drug interaction. Cancer patients receive many medications at the same time, which may not be combined with each other. The development of chemotherapy side effects is facilitated by polypragmasia, which increases the toxicity of cytostatics, causes atypical side effects.
Symptoms
The negative consequences of treatment are so diverse that it is not possible to collect all the information in one section. Therefore, the key points and features of the course of complications in patients with cancer are given below. The period of development of symptoms ranges from a few minutes with immediate allergic reactions to 5-10 years with cardiotoxicity, carcinogenesis and teratogenic effects.
One of the most frequent complaints during the course of chemotherapy is dyspeptic disorders. Most patients suffer from excruciating nausea and vomiting, which complicates daily activity and enteral nutrition. The situation is aggravated by mucositis-type mucosal lesions, decreased secretion of digestive glands and stool disorders. These factors cause severe vitamin deficiency and exhaustion.
Chemotherapy side effects include numerous infections. As a result of immunosuppression, a person becomes especially vulnerable, therefore, both infection from the outside and activation of existing infectious foci are possible. Cancer patients are characterized by the development of bacterial, fungal and protozoal pneumonia (39%), wound and postoperative infections (31%), urinary infections (8%) and fever of unknown origin (6%).
The consequences of treatment with cytostatics include numerous organ lesions. Cardiotoxicity is clinically manifested by pain in the left half of the chest, a feeling of heart failure or fading, shortness of breath at rest. With nephrotoxicity, there is a decrease in diuresis, a change in the color and density of urine, signs of azotemia. Neurotoxicity is manifested by memory impairment, paresthesia, impaired sensitivity and motor functions.
Diagnostics
To identify typical complications, such as vomiting, mucositis and nutritional insufficiency, routine examinations by an oncologist are sufficient, which are carried out to all patients on a course of chemotherapy. During the examination, complaints are collected and a standard physical examination is carried out. To diagnose other types of complications from taking cytostatics, the following research methods are prescribed:
- Ultrasound diagnostics. According to the indications, ultrasound of the abdominal cavity and retroperitoneal space, echosonography of the postoperative wound is performed. Targeted diagnosis of the liver is shown, since it is a typical site of metastasis of many tumors.
- Lung x-ray. Examination of the chest in two projections is carried out with clinical signs of pneumonia and to exclude lung metastases. When imaging inflammatory infiltrates, a CT scan of the lungs is prescribed to clarify the type of pneumonia.
- Blood test. A hemogram is necessary to determine the number of shaped blood elements, to detect anemia, agranulocytosis and other types of hematopoiesis disorders. In the biochemical analysis of blood, attention is paid to the level of protein, liver samples, the content of nitrogenous compounds.
- Microbiological diagnostics. At the signs of infection, serological reactions to antibodies are carried out, according to the clinical manifestations and the presumed etiology of the disease. Bakposev and PCR are widely used using different biomaterials: blood, feces, urine, sputum.
Treatment
In case of severe adverse reactions that threaten the life and health of the patient, it is possible to change the therapy protocol or cancel medications. In cases where it is impractical to change the treatment regimen, symptomatic therapy is selected to relieve the unpleasant manifestations that occur. Correction of complications is carried out according to an individual scheme, taking into account all the features of the disease in a particular patient.
Most patients are prescribed antiemetic drugs simultaneously with a course of chemotherapy to reduce or completely remove this complication. Persistent antiemetic effect is achieved in 70% of cases. In case of non-controlled vomiting, which is combined with diarrheal syndrome, a transfer to parenteral administration of nutritional mixtures or special mixtures for probe nutrition is considered.
Infectious complications make it necessary to prescribe antimicrobial drugs. To obtain a lasting therapeutic effect, it is often necessary to use several drugs simultaneously or to enhance therapy with reserve antibiotics. In case of fungal infections, systemic antimycotics are prescribed in long courses. According to indications, anti-candidiasis drugs are used to prevent invasive candidiasis.
Treatment of organ lesions is carried out differentially and with the participation of appropriate specialist doctors. Vitamin and mineral complexes, cardioprotectors, hepatoprotectors can be used to maintain the body’s work. For neurological complications, B vitamins, neurometabolites and nootropics are used. Poor emotional state of patients is a reason for the use of antidepressants.
Prognosis and prevention
In oncology, if possible, they find a balance between the medicinal effects of chemotherapy and its likely complications in order to carry out treatment as comfortably as possible for the patient. Typical complications, such as dyspepsia and mucositis, are successfully corrected, but immunosuppression and generalized infections can be fatal. Prevention consists in the rational selection of a treatment protocol and the appointment of symptomatic drugs against the background of chemotherapy.