Types of Cancer Treatments
Due to advances in the standard-of-care for cancer treatment in the last 30 years, the death rate from cancer has decreased substantially. Cancer treatment options continue to increase each year and because many of the most promising treatment options are new to the market, many of them can only be accessed by participating in a clinical trial.
It is important that you know all your treatment options and work closely with your physician on an individualized treatment plan.
The main types of cancer treatments include surgery, radiation therapy, chemotherapy, targeted therapies (including hormone therapy and immunotherapy) and stem cell transplantation for blood cancers. These treatments can be used alone, or in combination with other treatments, making it possible for patients to have individualized treatment plans that vary widely. Cancer treatment plans are developed based on the type of cancer, stage at diagnosis, molecular profile of the cancer, existing comorbidities, and patients’ individual preferences. Though there are thousands of potential cancer treatment regimens, the broad goals of therapy are to cure the cancer, control its growth, or ease associated symptoms.
Standard Cancer Treatments
Patients are most likely to receive surgery if they have a solid tumor that is localized (meaning the cancer has not spread). In patients with blood cancer or metastatic disease (cancer that has spread), surgery is generally not used as a treatment strategy.
Surgery is often the starting point in cancer treatment. From there, the treatment team determines whether additional therapy is needed and what type of therapy will advance treatment goals.
Radiation therapy, also known as radiotherapy, involves use of ionizing radiation to genetically damage cancer cells, thereby stopping their ability to divide and reproduce. The guiding principle of radiation therapy is to maximize the number of cancerous cells that are killed while leaving healthy cells intact.
Radiation therapy is a very common treatment strategy in cancer, with 50% of all cancer patients receiving it at some point. Radiation therapy is often used in conjunction with other treatments such as surgery, chemotherapy, and immunotherapy.
Radiation therapy contributes to 40% of curative treatments for cancer. Some early cancers can be cured with radiation therapy alone. Examples include early-stage squamous and basal cell skin cancers, prostate cancer, non-small cell lung cancer (NSCLC), certain lymphomas, and head and neck cancers.
(Source: Int J Med Sci 2012; 9(3):193-199)
Chemotherapy literally means ‘chemical therapy.’ Chemotherapy is designed with the singular goal of killing fast-growing cancer cells, but healthy fast-growing cells can also be affected, leading to various side effects – notably hair loss, nausea, fatigue, mouth sores, and infections.
Today, there are more than 100 different chemotherapies that can be combined together, or with other treatments, such as radiation therapy and surgery. Chemotherapy is often used in combination with other therapies, such as radiation or surgery, to increase the overall effectiveness of the treatment regimen, or to destroy cancer that has recurred and/or metastasized (spread to different parts of the body).
Increasingly, chemotherapy choices are driven by genomic considerations based on the molecular profile of the tumor. If a patient has a molecular profile test done, the treating physician has additional information that can guide decision-making, giving the patient access to more precisely tailored treatments known as targeted therapy.
Patients are affected by chemotherapy in various ways, and even if two patients receive the same regimen, they may have very different experiences. Learn more about chemotherapy side effects from the American Cancer Society.
Targeted therapies are a group of cancer therapies that target specific molecules on cancer tumors. These treatments are designed to block the function of cancer cells and stop them from growing, reproducing, and spreading.
Because some reproductive cancers, in both women and men, feed on hormones to grow, hormone therapy focuses on stopping hormones from being made or disrupting the conversion of hormones to cancer.
Immuno-oncology is not new, but is has evolved dramatically over the last decade. The general idea is to somehow get the immune system to attack cancer as a foreign presence. For some time, part of the standard of care for treating cancer has been using cytokines, specifically interferons and interleukins, which bind to antigens on tumor cells in order to elicit an immune effect. Targeted cytokine therapy is used in the treatment of certain types of leukemia, lymphoma, melanoma, Kaposi’s sarcoma, and kidney cancer.
Immunotherapy involves using the body’s own immune system to find and destroy cancer cells, just as it attacks other foreign invaders. Normally, the body’s immune system can detect an abnormal, potentially unhealthy cell; however, cancer cells have mechanisms for evading this normal detection process. Immunotherapy works by unleashing the patient’s own immune system against the cancer. A patient’s blood is removed and treated. The patient is then re-infused with immune-modified cells that hone in on the cancerous cells, essentially telling the immune system that this cell is suspect and should be destroyed.
In 2010, Provenge (sipuleucel-T) became the first approved cancer-treatment vaccine. Provenge is a vaccine for treatment of metastatic prostate cancer. The vaccine is made by taking blood from a patient through a catheter, combining it with immune cells that attack the cancer by targeting specific proteins in the body.
In 2011, the first checkpoint inhibitor, Yervoy (ipilumumab) was approved for the treatment of metastatic melanoma, ushering in a new era in immunotherapy. Checkpoint inhibitors are used to force cancer cells, which are hiding out, to be exposed to the immune system as harmful.
Many people heard about checkpoint inhibitors for the first time when former President Jimmy Carter revealed that he had been successfully treated with a PD-1 checkpoint inhibitor, Keytruda (pembrolizumab). In fact, his melanoma, which had previously spread to his liver and brain, had gone into remission.
Certain ‘checkpoint’ proteins, such as PD-1, function as ‘off’ switches in which they signal to the immune system that cells (both healthy and cancerous) that express these proteins are healthy—and therefore should not be destroyed. Checkpoint inhibitors are monoclonal antibodies that target these proteins and disrupt this process. As a result, cells which overexpress these proteins become vulnerable to attack by the immune system, allowing cancer cells to be destroyed.
There are currently four approved checkpoint inhibitors including Yervoy. In 2014, Opdivo (nivolumab) and Keytruda (pembrolizumab) were both approved for metastatic melanoma. The clinical trial program for these drugs is ambitious, which has led to additional approvals. In addition to melanoma, Opdivo is used to treat advanced lung cancer, kidney cancer, Hodgkin lymphoma, urothelial cancer, and squamous cell carcinoma of the head and neck. Keytruda is also used to treat advanced lung cancer and metastatic head and neck squamous cell carcinoma.
There are many other checkpoint inhibitors in development being tested in clinical trials, and there are trials that are currently evaluating treatment regimens that combine chemotherapy and immunotherapy.
Stem-cell transplantation is used to treat patients with certain types of leukemia, lymphoma, or multiple myeloma. By transferring stem cells (either the patient’s own stem cells) or donor cells, the patient’s treatment team can expose the patient to very high-dose chemotherapy and radiation, with the goal of killing all of the cancer cells. This can be a very effective approach, but it destroys the bone marrow, making it difficult for the body to recover and replenish red blood cells. However, when the stem cells are transplanted into the patient, the bone marrow regains platelet-producing capabilities.