Medical treatment is considered necessary as it aims to achieve a cure for any disease allowing the individual to live long. In cancer, if the medical treatment is ineffective in curing the disease, it shows efficacy in reducing the symptoms by reducing the tumor size and slowing down cancer growth. The medical treatment in cancer depends upon various factors such as type of cancer, stage of cancer, the patient’s health and preference as per the patient’s medical condition. The common approaches for medical treatment in cancer include:
- Surgery: It aims to remove cancer. It is the most common type of treatment. The surgeon removes the mass of cancerous cells and nearby tissues. It is mainly done to relieve the side effects caused due to tumors.
- Chemotherapy: It utilizes drugs which are effective in killing the cancerous cells. The drugs are either given orally or intravenously. Combinations of drugs are given to the patient simultaneously or one after the other.
- Radiation therapy: It uses x-rays, particles, or radioactive seeds to kill cancerous cells. Cancer cells have the capability of faster growth and proliferation when compared with normal cells in the body. Radiation therapy is capable of damaging cancer cells when compared with normal cells. It prevents the cancer cells from growing and dividing and leads to cell death. Different types of radiation therapy are available involving:
- External-beam radiation therapy
- Internal radiation therapy (Brachytherapy)
- Proton therapy
- Targeted therapy: It utilizes the drugs to inhibit the growth and spread of cancer cells to other body parts. It causes less harm to normal cells when compared with other treatments. The different types of targeted therapy include:
- Monoclonal antibodies
- Small-molecule drugs
- Apoptosis inducers
- Immunotherapy: It depends upon the body’s capability to fight infection while targeting the immune system. It uses substances made by the body or in a lab to help the immune system work harder or in a more targeted way to fight cancer. It enables the body to get rid of cancer cells.
- Hormone therapy: It uses hormones to kill cancer cells. Surgery and drugs are used to block natural hormones. It helps slow the growth of cancer cells. The surgery involves the removal of organs that make hormones, such as ovaries or testes. The drugs are given by injection or as pills.
- Cryoablation: It kills cancer cells with cold treatment. During cryoablation, a thin, wandlike needle (cryoprobe) is inserted through the skin and directly into the cancerous tumor. Gas is pumped into the cryoprobe to freeze the tissue. Then the tissue is allowed to thaw. The freezing and thawing process is repeated several times during the same treatment session to kill the cancer cells.
- Hyperthermia: It uses heat to damage and kills cancer cells without harming normal cells. The heat is delivered from a machine outside the body or through a needle or probe placed in the tumor.It includes:
- Local or regional hyperthermia
- Hyperthermic intraperitoneal chemotherapy (HIPEC)
- Hyperthermic intrathoracic chemotherapy (HITHOC)
- Whole-body hyperthermia
- Laser therapy: It uses an arrow, a focused beam of light, to destroy cancer cells. It is often given through a thin, lighted tube inside the body. Thin fibers at the end of the tube direct the light at the cancer cells. Lasers are also used on the skin.
- Radiofrequency ablation: It utilizes electrical energy to heat cancer cells, resulting in cancer cells’ death. During radiofrequency ablation, a thin needle through the skin or an incision is passed into the cancer tissue. High-frequency energy passes through the needle and causes the surrounding tissue to heat up, killing the nearby cells.
- Chromodulation therapy: It involves the integration of chemotherapy drugs at optimal times during the entire day at which cancer cells become more susceptible and less likely to be damaged by treatment.
- Low-dose metronomic chemotherapy: The administration of metronomic chemotherapy is prolonged, repetitive and frequently by providing low doses of chemotherapy drugs. It involves several advantages involving the interference with the ability of cancer to create its essential blood supply and reducing the ability of cancer to become resistant.
Common side-effects and symptoms of medical treatment:
Surgery: Possible side-effects of surgery are caused due to the drugs used and the patient’s overall health. The more complex the surgery evolves, the more risk of side effects. Minor operations and taking tissue samples such as biopsies have less risk when compared to any bigger surgery. Pain at the surgery site is the most common symptom among cancer patients. Infections at the site and reactions to the drugs used to numb the area (local anesthesia) are also possible. Some of the common side effects during surgery include:
- Blood clots
- Damage to nearby tissues
- Drug reactions
- Damage to other organs
- Slow recovery of other body functions
Chemotherapy: It causes side effects, mainly among those patients who are under medication or have a history of chronic diseases. The side effects of chemotherapy depend upon the drugs or combination of drugs prescribed to the patient. Some common side effects of chemotherapy include:
- Fatigue: It is the feeling tired or exhausted even after getting enough sleep.
- Hair loss: It starts after the first several weeks of chemotherapy and tends to increase 1 to 2 months into chemotherapy. The doctor can predict the risk of hair loss depending upon the drugs and doses received.
- Pain: chemotherapy causes pain, including headaches, muscle pain, stomach pain and pain from nerve damage such as burning, numbness, or shooting pains, usually in the fingers and toes.
- Mouth and throat sores:Chemotherapy damages mouth and throat cells, causing painful sores in these areas. Mouth sores usually happen 5 to 14 days after treatment. It is also essential to watch for infection in these sores.
- Diarrhea: Chemotherapy causes loose or watery bowel movements.
- Constipation: Not having a bowel movement is caused due to chemotherapy. Other medicines, such as pain medication, can also cause constipation.
- Nausea and vomiting: These side effects depend on the specific drugs and dose given during the chemotherapy.
- Blood disorders: Chemotherapy affects the process of making new blood cells in the bone marrow causing side effects from having too few blood cells.
- Nervous system side effects: Some drugs cause nerve damage. This can cause nerve or muscle symptoms such as tingling, burning, weakness or numbness, weakness, soreness, tiredness, or achy muscles, loss of balance, shaking or trembling, stiff neck or headache, and problems seeing or hearing, or walking normally, and feeling clumsy.
- Changes in thinking and memory: Some people have trouble thinking clearly and concentrating after chemotherapy.
- Sexual and reproductive issues: Chemotherapy affects the fertility rate of individuals. Chemotherapy can also harm an unborn baby. This is especially true during the first three months of pregnancy when the organs are still developing.
- Appetite loss: It results in loss of weight and loss of nutrients that are required by the body.
- Heart issues: Some types of chemotherapy can affect heart functioning.
- Radiation therapy: It causes the occurrence of early side effects and late side effects. Early side effects happen during or shortly after treatment and usually, go away within a few weeks after treatment ends. The most common early side effects are fatigue (feeling tired) and skin changes. Other early side effects usually are related to the area being treated, such as hair loss and mouth problems when radiation treatment is given to this area. The late side effects can take months or even years depending on the location treated and the radiation dose used. Common side effects of radiation therapy include:
- Fatigue: Fatigue felt during radiation treatment does not get better with rest. It can last a long time and affects the usual activities.
- Skin problems: The radiation treatment area is observed with red, irritated, swollen, blistered, sunburned, or tanned. After a few weeks, the skin becomes dry, flaky, or itchy, or it may peel. This is sometimes called radiation dermatitis.
- Hair loss: Radiation therapy results in thin hair or loss of hair in the region of being treated.
- Low blood counts: Radiation therapy causes changes in the blood count levels by lowering the blood cells.
Targeted therapy: The side effects of targeted therapy depends on the type of targeted therapy received by the patients and how their body reacts to it. The most common side effects include:
- Problems with blood clotting and wound healing
- High blood pressure
- Mouth sores
- Nail changes
- The loss of hair color
- Skin problems such as rash or dry skin
Immunotherapy: Immunotherapy causes side effects, many of which happen when the immune system may act against healthy cells and tissues in the body. The common side effects of immunotherapy include:
- Nausea and vomiting
- Muscle or joint aches
- Trouble breathing
- Low or high blood pressure
- Swelling and weight gain from retaining fluid
- Heart palpitations
- Sinus congestion
- Organ inflammation
Cryoablation: In the days after the procedure of cryoablation, mild symptoms such as an achy chest and discomfort or bruising in the area where the catheter was inserted are observed in the patients. Some of the common side effects of cryoablation include:
- Complications from anesthesia, such as trouble waking up or nausea.
- Damage to surrounding structures.
- Fluid collection in surrounding areas.
- Infection from any opening in the skin.
- Nerve damage leading to weakness or numbness.
Hyperthermia: It uses perfusion techniques such as heat to damage and kill cancer cells without harming normal cells. Its common side effects include:
- Blood clots
- Damage to the normal tissues
- Nausea and vomiting
Laser therapy: Laser therapy has some risks. The risks include:
- Changes in skin color
- Confusion after waking from the operation
- Heart attack
Radiofrequency ablation: It causes long-term side effects while damaging the surrounding blood vessels and nerves during needle insertion resulting in excessive bleeding and/or irreversible neurologic damage causing long-term numbness and tingling. Heat damage to structures adjacent to the target nerve. The common side effects of radiofrequency ablation include:
- Shoulder pain
- Capsular hematoma
Management of the side effects of the medical treatment:
Surgery: The surgical team will take various steps to reduce your risk of side effects and complications of surgery. It includes having and cleaning the area before cutting the skin to avoid infection, using special leg pumps and low-dose blood thinners to avoid blood clots, and breathing treatments (respiratory therapy) to help prevent pneumonia. The information regarding the possible complications of surgery and what can and will be done to help prevent them needs to be asked from the surgeon.
Chemotherapy: The side effects of chemotherapy can be managed by regularly communicating with the cancer care team regarding the side effects. It may be helpful to track side effects over time and share that information with the care providers. Some of the ways of managing the side effects are discussed below:
- Pain can be managed by giving pain-relieving medications
- Blocking pain signals from the nerves to the brain with spinal treatments or nerve blocks
- Adjusting your dose of specific drugs
- Eating a healthy diet and keeping the mouth and teeth clean can lower your risk of mouth sores.
- Preventing diarrhea or treating it early helps from getting dehydrated (losing too much body fluid).
- The risk of constipation is lowered by drinking enough fluids, eating balanced meals, and exercising regularly.
- Medications are given before and after each dose of chemotherapy that can usually prevent nausea and vomiting.
- Routine check-ups for blood counts using two types of tests involving complete blood count (CBC) and platelet count.
- The doses of chemotherapy are adjusted to prevent low blood counts.
- Drugs are available to treat blood disorders.
- The drugs help the bone marrow make more blood cells.
- They can help prevent leukopenia in people with a high risk.
- Lower dose of chemotherapy is given to minimize the adverse impact of nerve damage.
- Follow-up care is provided to the cancer patients involving regular physical examinations, medical tests, or both.
Radiation therapy: The side effects of radiation therapy are managed by using radioprotective drugs. These drugs are given before radiation treatment to protect certain normal tissues in the treatment area. The one most commonly used drug is amifostine. This drug may be used in people with head and neck cancer to reduce the mouth problems caused by radiation therapy. Some other methods of managing the side effects of radiation therapy include:
- Do not wear tight, rough-textured, or stiff clothes over the treatment area.
- Do not rub, scrub, scratch, or use adhesive tape on the treated skin
- Do not put heat or cold (such as a heating pad, heat lamp, or ice pack) on the treatment area
- Protect the treated area from the sun
- Use lukewarm water and mild soap only
- The radiation oncologist may change the treatment schedule or arrange a break if the side effects are severe.
Targeted therapy: The treatment team can help you manage any side effects of targeted therapy, which often need a different approach from other cancer treatments’ side effects. Some other methods of coping with the side effects of target therapy include:
- Applying topical minoxidil to treat the hair loss
- Educating patients to avoid friction, wearing gloves or socks to protect the nails, and limiting pressure on the nails.
- Antihistamine or steroid cream is prescribed to help with itching and dry skin.
- The dose of the targeted therapy drug is reduced to see if that helps ease the side effects.
Immunotherapy: Because immunotherapy works differently from other cancer treatments, it’s essential to work closely with your treatment team to monitor any side effects and how cancer responds. The following points should be considered for managing the side effects of immunotherapy:
- The potential side effects should be discussed with the cancer specialist before immunotherapy.
- Some tests are conducted to check that the patient is well enough to have immunotherapy.
- Throughout treatment, the team will regularly test the blood and ask the patient questions to check for early signs of side effects.
- Do not start any new medicines, including anti-inflammatory steroids, herbal therapies or over-the-counter medicines, without consulting the oncologists.
- If side effects become too severe, the immunotherapy must be stopped permanently.
The clinical evidence has shown efficacy in working against cancer growth or spread, improving survival, or working with other treatments or therapies to enhance their anti-cancer action. Some of them are discussed below:
- Surgery has shown efficacy at an early stage of cancer, followed by radiation therapy and chemotherapy (Arruebo et al., 2011).
- Targeted therapies have been effective in promoting cell survival and targeting cells that control whether cells live or die (Luo et al., 2003).
- Cryoablation shows efficacy in treating benign and malignant primary tumors (Gage et al., 1998).
- Improved survival rates have been observed in the case of glioblastoma while integrating multimodal immunotherapy (Van Gool et al., 2018).
- The hyperthermia therapy shows a good tolerance level with intensity-modulated radiotherapy in the case of esophageal cancer (Liming et al., 2017).
- Radiation therapy effectively reduces cancer cells’ ability to proliferate by damaging the DNA (Jackson & Bartek, 2009).
- Arruebo M, Vilaboa N, Sáez-Gutierrez B, et al. Assessment of the evolution of cancer treatment therapies. Cancers 2011; 3: 3279–3330. https://doi.org/10.3390/cancers3033279
- Luo J, Manning BD, Cantley LC. Targeting the PI3K-Akt pathway in human cancer: rationale and promise. Cancer Cell 2003; 4(4): 257–262. https://doi.org/10.1016/s1535-6108(03)00248-4
- Gage AA, Baust J. Mechanisms of tissue injury in cryosurgery. Cryobiology 1998; 37(3): 171–186. https://doi.org/10.1006/cryo.1998.2115
- Van Gool SW, Makalowski J et al. The induction of immunogenic cell death (ICD) during maintenance chemotherapy and subsequent multimodal immunotherapy for glioblastoma (GBM). Austin Oncology Case Reports. 2018;3(1):1010.
- Liming S, Yongling J, Qiner W, Xianghui D. Regional hyperthermia combined with radiotherapy for esophageal squamous cell carcinoma with supraclavicular lymph node metastasis. Oncotarget. 2017 Jan 17;8(3):5339–5348.https://doi.org/10.18632%2Foncotarget.14148
Jackson SP, Bartek J. The DNA-damage response in human biology and disease. Nature. 2009;461:1071–1078. https://doi.org/10.1038/nature08467