Is Cancer in Us?

Friday, December 15, 2023

Part III Management of the Side Effects of Chemotherapy and Radiotherapy

Chapter 2

Drugs and Potential Drugs as Chemoprotectors

In this chapter, we will discuss drugs and potential drugs (often referred to as agents) that may be used before chemotherapy to reduce the side effects. These drugs/agents are often referred to as chemoprotectors. Examples of chemoprotectors are listed below based on the individual targets to be protected.

1. Drugs to Increase White Blood Cell Count

Filgrastim

Filgrastim is a 175-amino acid human granulocyte colony-stimulating factor (G-CSF) manufactured by recombinant DNA technology in E Coli. It is a glyprotein naturally produced by a number of different tissues to stimulate the bone marrow cells to produce granulocytes and release them into the blood.

Filgrastim is used to stimulate the proliferation and differentiation of neutrophils, which are the most abundant type of WBCs. It is marketed as Neupogen® by Amgen, as Religrast® by Reliance Biopharmaceuticals, and as ShilgrastTM by Raichem Lifesciences.

Sargramostim

Sargramostim is a WBC stimulant sold as Leukine® by Genzyme. It is a human granulocyte macrophage colony stimulating factor (GM-CSF) produced by recombinant DNA technology in a yeast, S. cerevisiae. Sargramostim is a glycoprotein having 127 amino acids. Its amino acid sequence is different from the natural human GM-CSF by a substitution of leucine at position 23. It was originally approved by the FDA in March, 1991 for use following autologous bone marrow transplantation (BMT) and was approved in December 1991 to prevent death following BMT engraftment delay or failure. In September of 1995, it was subsequently licensed to shorten the time for neutrophil recovery to prevent early death from life- threatening infections following chemotherapy for older patients suffering from acute myelogenous leukemia (AML).

Disclaimer: This blog is written solely for informational purposes. It does not constitute the practice of any medical, nursing or other medical professional health care advice, diagnosis, or treatment. All contents posted are extracted from the book, "SIDE EFFECTS OF CHEMOTHERAPY AND RADIOTHERAPY", prepared by Dr. Jiajiu Shaw, Dr. Frederick Valeriote, and Dr. Ben Chen.

Monday, December 4, 2023

Part III Management of the Side Effects of Chemotherapy and Radiotherapy

Chapter 1

How to Cope with the Side Effects

Dealing with Type 3 Side Effects

Liver and Kidney Injuries

Liver is the most critical organ in the body’s metabolism and detoxification. In addition, it is a vital organ capable of regenerating some of the lost tissue. For liver injury, some drugs may be helpful in protecting liver. For example, amifostine (Trade name Ethyol®) is indicated to reduce the cumulative renal toxicity associated with repeated administration of cisplatin in patients with advanced ovarian cancer. Other than amifostine, some natural products, such as milk thistle, may be useful in protecting or improving liver health.

Kidney toxicity is also referred to as nephrotoxicity, which is one of the most common toxicity resulted from chemotherapy. There are two important indicators of nephrotoxicity: BUN and creatinine. When kidney is damaged, blood levels of BUN and creatinine are usually elevated. Because urea is a waste form of nitrogen in the body, elevated BUN levels indicate that there is extra nitrogenous waste in the blood stream not properly filtered off by the kidney. As to creatinine, it is produced from creatine, an important molecule in energy production of muscle. Creatine is constantly converted into creatinine, which is constantly filtered off by the kidneys and disposed of in the urine.

In other words, kidney is critical in filtering off both BUN and creatinine to remove waste from the body. Therefore, when kidney function is affected by chemotherapy, blood levels of both BUN and creatinine are elevated.

Peripheral Neuropathy

Neuropathy means disease or dysfunction of the nerves, which can be a side effect of chemotherapy. For peripheral neuropathy, the most commonly affected areas are the tips of fingers and toes. Common symptoms of peripheral neuropathy include tingling, burning, numbness/pain in the affected areas, and loss of balance, although sometimes other areas may also be affected. Massage one’s hands and feet may help improve blood circulation and temporarily relieve the pain. For a patient with peripheral neuropathy, he/she should see a doctor about any neuropathy symptoms to prevent further nerve damage.

Monday, July 11, 2022

Part III Management of the Side Effects of Chemotherapy and Radiotherapy

Chapter 1

How to Cope with the Side Effects

Dealing with Type 2 Side Effects

Anemia (lower levels of red blood cells)

As mentioned before, both chemotherapy and radiotherapy can lower RBC count and result in anemia. Generally, the RBC count for a healthy adult is about 5 x 10⁶/µL. Because chemotherapy or radiotherapy could damage bone marrow, which produces RBCs, RBCs are not replaced at the same rate as they are being destroyed. As a result, the RBC count becomes much lower than that in a healthy person, a situation referred to as anemia.

If patients become anemic due to cancer therapies, they will have reduced blood levels of RBCs, which carry oxygen from the lungs to the body’s muscles and other organs. As a result, patients can become tired more easily; patients may also feel dizzy or light-headed when they quickly stand up from a crouching position. Although a normal healthy body can replenish lower levels of RBCs, it does take time. In addition, multiple treatments of chemotherapy or radiotherapy can hamper the reproduction process of RBCs. During the cancer therapy, when the RBC count is significantly below acceptable levels, it could cause a physician to temporarily suspend the chemotherapy or radiotherapy. In more serious conditions, blood transfusion or treatment by a specific bone marrow stimulating drug(s) may become necessary. Some of these drugs will be briefly described in the following sections.

Otherwise, what can a patient do? First, a patient should watch the diet. For example, eat nutritious food including liver, red meat, and green vegetables (such as spinach) to supplement iron in blood, which is important for maintaining RBC levels. Most of the body's iron is bound to hemoglobin in RBCs. When red blood cells die, the released iron is carried by transferrin (iron-binding plasma glycoprotein) to the bone marrow, to make new RBCs.

Iron pills can be very useful for treating anemia, but they should be taken under the prescription of the physician because of the potential side effects. When too much iron is taken, it could slowly accumulate and could become toxic in different organs, including the liver and heart.

In addition to iron supplement, patients should take some other dietary supplements, such as vitamin C, which is important for iron absorption, and vitamin B₁₂, which is important in maintaining normal RBC formation. Furthermore, patients should rest often to conserve energy and not to conduct any vigorous exercises.

Leukopenia (low WBC count)

There are reports about a natural chemical, hesperidin, which may be helpful in increasing WBC count. Hesperidin is abundant in the peels of citrus fruit, including orange, lemon, and grapefruit. One can be creative in using the peel by blending the peel in juice or in food for easier consumption.

Thrombocytopenia (low platelet count)

Although it does not happen for all chemotherapeutic agents, thrombocytopenia does happen to many patients. Thrombocytopenia is not uncommon for acute leukemia patients treated with radiotherapy; under serious condition, it could even be life-threatening. Similar to anemia and neutropenia, thrombocytopenia is usually temporary. When the platelet count is low (between 15,000 and 30,000 per µL), unexplained bruises may happen. When the platelet count is even lower (under 10,000 per µL), a patient may need a platelet transfusion.

As a patient, one must be careful in daily activities and try to avoid any injury because the bleeding might take much longer than normal to stop. In addition, patients need to be careful in conducting any physical activities to avoid cutting/bleeding.

Hair Loss

Not all chemotherapy drugs cause hair loss. Some people may lose all the hair on their heads and other body hair, while others may not lose much hair. For many people, hair loss may be a difficult aspect to deal with. In this case, using a wig to cover the head could make a patient feel more comfortable. Several weeks after the therapy, the hair should begin to grow back; the new hair may be slightly different in color and texture. Usually, the new hair will be thin and soft, like baby’s hair, but will often return to its original color and texture after several months.

Diarrhea or Constipation

Crypt cells in the intestine are likely to be attacked by chemotherapy drugs and may result in diarrhea. Some chemotherapeutic drugs may cause constipation. Patients with constipation should consider taking a stool softener, such as Colace® or Senekot®. Also, drinking a lot of liquid may help prevent constipation. If a patient has several watery stools or constipation, the patient may want to call his/her doctor or nurse.

Mouth Sores

Because epithelial cells in the mouth and esophagus are fast dividing, they are easily damaged by chemotherapy and radiotherapy. As a result, mouth sores occur often with chemotherapy and radiotherapy. For a patient to assuage that, rinse the mouth often with salty water. If a patient develops painful mouth sores and the situation is not relieved, one should call his/her physician or health practitioner and a special mouth rinse may be prescribed for the patient. If a commercial mouth wash is used, avoid those that may be irritating to the mouth.

Saturday, February 19, 2022

Part III Management of the Side Effects of Chemotherapy and Radiotherapy

Part III

Chapter 1

How to Cope with the Side Effects

Coping with the Side Effects

Before, during, and after radiotherapy or chemotherapy, there are some prescription drugs and natural products that can be used to reduce specific side effects induced by the therapy. In addition, there are also some activities that patients can do to reduce the discomfort from cancer therapies. Let’s look at them according to the types of side effects.

Dealing with Type 1 Side Effects

In general, patients should first consult their doctors to find out what medications are expected to work best for their situations. Other activities are described under individual side effects below.

Fever and Infection

Chemotherapy often lowers WBC count in the blood resulting in neutropenia. Because white blood cells are very important in fighting against infection, when a patient’s WBC count is lower than normal level, the patient is more susceptible to infection.

To reduce the chance of infection, patients should avoid going to public areas, such as theater and shopping mall. Also, avoid close contact with anyone who is ill. Wash hands frequently and when washing hands, use appropriate hand soap especially when the hands are visibly soiled. In recent years, alcohol-based hand sanitizer is becoming popular and it can be very effective in reducing the number of germs. In addition, do not eat raw food including fish, beef, oyster, and food containing raw egg. Thoroughly wash the vegetables and fruits for salad. Wash the cutting board especially after cutting raw meat, poultry, or fish. A patients should call his doctors if the body temperature reaches 101 °F (or 38.3 °C) or higher.

Flu-Like Symptoms

After a chemotherapy treatment, some people may experience flu-like symptoms such as pains and muscle aches. If not serious, patients can take over-the-counter medications such as Tylenol or Advil to relieve the pain. However, if the symptom persists, patients should contact their doctors for prescription drugs. In many states and Washington D.C., marijuana may be prescribed by physicians for pain management.

Nausea and Vomiting

For the management of nausea, patients should try not to skip meals. An empty stomach can worsen the symptom. Eat small and light meals. Drink lots of fluids, such as water, tea, and juice. Acupressure is being used by some people to reduce nausea basically by pressing a specific acupressure point near the base of the arm. There are special wristbands available for such an acupressure; the wristband usually has a knob to apply pressure to the correct spot. Further, there are some anti-nausea over-the-counter drugs available to prevent and treat nausea and vomiting due to chemotherapy.

Fatigue

Fatigue is a common symptom for people treated for cancer. For some, the fatigue may last a long time after treatment, and it can discourage them from physical activity. However, proper exercise can actually help patients reduce fatigue. Physical therapy can also help patients maintain strength in the muscles, which could help fight the sense of depression that sometimes comes with physical fatigue.

Most cancer drugs can reduce the RBC count and may cause anemia, which can make patients feel tired easily. Most people have to make some adjustment in work and family responsibilities. For anemia patients, it’s a good idea to plan their major activities and try to maintain their regular daily activities as much as possible. The fatigue should gradually go away after the patients recover from chemotherapy.

Doing regular exercise such as yoga, taichi, and walking may be helpful in relaxation. If necessary, physicians can prescribe iron supplement or other newer drugs to boost the blood cells. These include Epogen (by Amgen), Neupogen (by Amgen), and Leukine (by Berlex), which function as colony-stimulating factors because of their ability to stimulate the formation of blood cells in the bone marrow.

Appetite and Taste Changes

During chemotherapy, one may lose appetite and becomes more sensitive to odors. As a patient becomes healthier, his/her appetite will improve. Again, one should try to stay with healthful food (low fat, low calorie, and high fiber) and drink a lot of liquid. Also, it’s a good idea to avoid spicy food. For some people, eating too much spicy food can result in diarrhea.

With a loss of appetite, important nutrients may be lacking. Suitable dietary supplement products may be used to supply needed nutrition.

Menopause

Depending on a woman’s age and the type of chemotherapy administered, chemotherapy may temporarily stop the periods. As a result, one may experience symptoms such as hot flashes, decreased libido, vaginal dryness, mood changes, and sleeping disturbances. If a patient experiences any of these symptoms, she should call her doctor or nurse about suitable treatment for the symptoms. Meanwhile, consider eating soy products (such as soy milk and tofu) which may reduce hot flashes. Wear light cotton pajamas to help prevent overheating when sleeping. Use vaginal moisturizers or other water based lubricants as needed.

Wednesday, February 2, 2022

New US Patent Issued

A new U.S. patent related to radiotherapy and chemotherapy has just been issued to us.

Title: Small Molecules and Methods of Reducing Injuries Caused by Radiation or Chemicals

Patent No.: 11,236,056

Date of patent: February 1, 2022

If you are interested in learning more, please visit the US Patent and Trademark Office at

https://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=%22shaw,+jiajiu%22&OS=%22shaw,+jiajiu%22&RS=%22shaw,+jiajiu%22

It is very much appreciated that you spend your time reading my blog. In addition to sharing the technical/non-technical info about cancer, I am still doing research on improving methods of treating cancer. The issuance of this patent is just another small step forward. There is still a long way to go in order to continue the development of this agent.

Again, thank you very much for your attention.

Thursday, December 30, 2021

Part III Management of the Side Effects of Chemotherapy and Radiotherapy

Part III

Chapter 1

How to Cope with the Side Effects

Three Types of Side Effects

In general, side effects from chemotherapy and radiotherapy can be divided into three types. The first is a set of physiological responses, which are acute and the least concerning, including appetite loss, nausea and vomiting, weakness and fatigue, as well as flu-like symptoms; all of these can be managed by specific actions.

Fig. 3.1 Common cell types in a cell renewal system

The second type of side effects is more severe and may damage cells in renewal tissues. There are a number of such cell renewal tissues in the body encompassing the hematopoietic system, the gastrointestinal tract, skin, hair, gonads, and cornea. Fig. 3.1 shows the common cell types in a cell types in a cell renewal system. The first and basic cell type is the stem cell – destroy all of these and the tissue gradually disappears. These cells are especially sensitive to both radiation and chemotherapeutic agents, and more so when they are proliferating. If over 99.9% of the stem cells are destroyed, the renewal tissue can’t recover by itself and the host will die. If stem cells are not totally destroyed, stem cell transplant and some protective agents can ameliorate some of the damage. The “committed” stem cells and differentiating cells (which may require proliferation) are also sensitive to chemotherapy and radiotherapy since they are proliferating just like the cancer cells. Finally, the differentiated cells such as platelets and red blood cells are resistant to chemotherapy. However, since the differentiated cells have a specific half-life, they are “used up” and may not be replaced as the stem cells and differentiating precursor cells have been destroyed.

The third type of side effects is direct damage to cells in major organs such as liver, heart, and brain. These are non-proliferating cells, and like the differentiated cells discussed above and relatively insensitive. However, some drugs do have selective toxicity to specific organs such as anthracyclines and cardiac toxicity.

Monday, December 20, 2021

Part III Management of the Side Effects of Chemotherapy and Radiotherapy

Part III

Chapter 1

How to Cope with the Side Effects

The major side effects of chemotherapy and radiotherapy include tissue/organ injury which occasionally may be fatal. In addition, these side effects may prevent doctors from delivering the prescribed dose of therapy according to the predetermined schedule in the cancer treatment plan. It is important to understand that the expected outcome from therapy is based on delivering treatment at the dose and schedule according to the well-designed and predetermined treatment plan. In other words, not only are the side effects of chemotherapy or radiotherapy undesirable, they may also limit a patient’s ability to accept the complete therapeutic regimen (both dose and schedule) to achieve the best outcome.