Chemotherapy is the treatment of a disease using chemicals that cure the disease, but do not cause the patient to die. Paul? Enrich, who first used the term, is the director of an institute for the study of infectious diseases and serums.
Clinical applications of chemotherapy
1. Systemic chemotherapy for advanced or disseminated tumors
Because of the lack of other effective treatments for patients with these tumors, chemotherapy is often used at the outset, with the immediate goal of achieving remission. This chemotherapy is usually referred to as Induction Chemotherapy. If the initial chemotherapy regimen fails and is replaced with another regimen, it is called Salvage Treatment.
2.Adjuvant Chemotherapy
Adjuvant chemotherapy is chemotherapy given after local treatment (surgery or radiotherapy) to prevent the recurrence of metastases in microscopic lesions that may exist. For example, postoperative adjuvant chemotherapy for patients with osteosarcoma, testicular tumor and high-risk breast cancer can significantly improve the outcome and increase the survival rate or disease-free survival rate.
3.Neoadjuvant Chemotherapy
Neoadjuvant chemotherapy can be used before surgery or radiation therapy for tumors that are relatively limited in clinical practice, but have some difficulty in surgical resection or radiation therapy. The purpose is to hope that the tumor shrinks after chemotherapy, thus reducing the extent of resection and the disability caused by surgery; secondly, chemotherapy can inhibit or destroy the possible microscopic metastases and improve the survival rate of patients. It has been proved that neoadjuvant chemotherapy for bladder cancer, breast cancer, laryngeal cancer, osteosarcoma and soft tissue sarcoma, non-small cell lung cancer, esophageal cancer and head and neck cancer can reduce the scope of surgery or turn inoperable tumors into resectable tumors after chemotherapy.
4.Special route chemotherapy
(1) Intracavitary therapy includes cancerous intra-thoracic, intra-abdominal and intra-pericardial effusion. Usually, chemotherapeutic drugs (such as mitomycin, cisplatin, 5-fluorouracil, bleomycin) are dissolved or diluted with appropriate amount of fluid and injected into the body cavity of various lesions through the draining catheter, so as to control the malignant body cavity effusion.
(2) Intralesional chemotherapy Leukemia and many solid tumors can invade the central nervous system, and the meninges in particular are the most susceptible. Treatment is usually administered intrathecally by thoracic spinal puncture to allow for a higher concentration of drugs in the cerebral fluid for therapeutic purposes. The drugs commonly used intrathecally are methotrexate and cytarabine.
(3) Arterial cannulation chemotherapy, such as external carotid artery branch cannulation for head and neck cancer and hepatic artery cannulation for primary liver cancer or liver metastasis cancer.
Principles of rational drug use
Although there are more than 40 commonly used anti-tumor drugs and new drugs are still being developed, in order to achieve good efficacy, there must be a reasonable treatment plan, including the timing, selection and combination of drugs, the order of administration, dose, course of treatment and interval time, etc., in order to select the combination chemotherapy plan comprehensively, reasonably and effectively. Usually, the following principles should be considered in the composition of the combination chemotherapy regimen.
1, the use of drugs with different mechanisms of action in order to play a synergistic role.
2, the drugs should not have similar toxicity, so as not to add up to toxicity and be intolerable to patients.
3, the single drug must be effective.
Chemotherapy precautions
(1) The diagnosis must be clear before starting treatment. Leukemia, multiple myeloma and malignant histiocytoma must be diagnosed hematologically and with bone marrow cytology. Malignant lymphoma and various other solid tumors must be diagnosed by local tissue pathology. Chemotherapeutic drugs are generally not used for diagnostic treatment, let alone as placebo, to avoid unnecessary losses to the patient.
(2) Patients with good general condition, normal blood picture and liver and kidney function are required to tolerate chemotherapy. The type and dose of drugs should be carefully considered for any of the following conditions: [1] old and frail; [2] previous multiple chemotherapy or concurrent with radiotherapy; [3] abnormal liver and kidney function; [4] obvious anemia; [5] white blood cells or platelets below normal values; [6] malnutrition and significant decrease in plasma protein; [7] tumor bone marrow metastasis; [8] adrenal cortical insufficiency; [9] There are fever, infection or other complications; [10] Cardiomyopathy, etc.; [11] Chronic pulmonary insufficiency.
Reasons for chemotherapy failure
1.Patient side
The bone marrow and other important organs (liver, kidney, heart, lung, etc.) are not fully functional, and the general condition of the patient is too poor to tolerate chemotherapy.
2.Tumor side
Primary or secondary drug resistance; low proliferation ratio in quiescent cells; excessive tumor load, tumor cells above 1011.
3.Drug aspect
Not strong selectivity, little difference in damage to tumor and normal tissue cells; ineffective or too ineffective to GO stage cells; cannot act on tumor cells in the “refuge”, such as cannot pass the blood-brain barrier and enter the skull; the most effective use method has not been found.
Chemotherapy side effects
The most common side effects of chemotherapy are nausea and vomiting. In medicine, nausea and vomiting are often divided into two categories: early stage and late stage. Drugs are more effective in controlling the symptoms of nausea and vomiting in the early stages, while those in the late stages are difficult to control. There are at least two causes of nausea and vomiting: the first cause is due to mucositis, which is mainly due to inflammation of the digestive tract mucosa and signaling from the nervous system. The second cause is mainly due to brain signaling.
Nausea and vomiting usually occur a few hours after chemotherapy and do not last long. Severe nausea and vomiting lasting several days is uncommon. Patients with unusual nausea, vomiting for more than a day, or nausea so severe that they cannot even swallow liquids, should always inform their doctor or nurse.
Changes in diet and antiemetic medications can reduce both symptoms. Different antiemetics work for different people, so it is inevitable that you will try several before your symptoms are relieved. Don’t give up easily, and you should continue to work with your doctor to find out what works best for you.
About half of all chemotherapy patients feel emotionally unstable before chemotherapy, which is called pre-treatment nausea. The best way to deal with pre-treatment nausea is to use relaxation techniques. (We’ll discuss this later).
You can also try the following.
1) Don’t eat too much so your stomach doesn’t feel too full. Eat more meals and less throughout the day.
2) Don’t drink with your meals; they must be an hour before or after.
3) Eat and drink slowly.
4) Do not eat sweet, fried or fatty foods.
5) Eat cold or at room temperature so you don’t smell bad.
6) Chew your food slowly to aid digestion.
7) If you feel nauseous in the morning, then eat dry foods such as cereal, toast or crackers before you get up. (If you have a sore mouth and throat or dry mouth, don’t eat these things.)
8) Drink cold, clean beverages, such as apple juice, tea or deflated ginger beer.
9) Suck on ice cubes, mints or sour candy. (Don’t eat these things if you have a sore mouth and throat.)
10) Avoid exposure to odors that make you nauseous, such as oil smoke, cigarettes and perfume.
11) Rest in a chair after a meal, but at least two hours after the meal before lying down.
12) Wear loose fitting clothes.
13) When you feel nauseous, you can slowly take deep breaths.
14) You can distract yourself by talking with friends or family, listening to music, watching movies or TV.
15) Use ways to relax a little.
If you often feel nauseous during chemotherapy, then do not eat at least a few hours before chemotherapy.