When mutations occur in the DNA within cells in our bodies and these cells survive to divide and replicate, this can cause cancer. This can happen in cells located almost anywhere in the body—for example, in the blood, skin, lymph nodes, breasts—as well as vital organs such as the brain, liver, lungs, and kidneys. 

What is so problematic about cancer cells is that they multiply quickly and uncontrollably, creating copies of themselves and passing along their defective DNA. To stop their rapid, erratic division, doctors often turn to chemotherapy—drugs designed to destroy cancer cells.  

Chemotherapy or “chemo” can be used to cure cancer, shrink cancerous tumors, prevent cancer from spreading (metastasizing) elsewhere in the body or to relieve discomfort from a growing tumor.

“Cancer chemotherapy has evolved from a last resort 60 years ago to treatment that now can cure patients or markedly prolong their lives, often with far fewer side effects than with the original drugs decades ago,” says Joseph Paul Eder, MD, a Yale Medicine medical oncologist. He is the clinical director of Yale Cancer Center at Smilow Cancer Hospital’s Early Drug Development Program. 

In addition to chemotherapy, other types of cancer treatment include surgery, radiotherapy, immunotherapy, targeted therapy, or a combination of these approaches. If you or a loved one is diagnosed with cancer, a Yale Medicine medical oncologist will work with you and a team of doctors at Yale Cancer Center at Smilow to determine the best way to treat your cancer, based on the latest research and using the most advanced technology available.

Chemotherapy refers to drugs used to kill cancer cells or prevent them from multiplying and passing along their DNA mutations. Chemo is also used to shrink tumors that are causing pain and discomfort. It may be used to help make other treatments more effective. It is also used to help kill cancer cells that threaten to spread through the bloodstream, called metastatic or secondary cancer.

There are four main types of chemotherapy:

• Neoadjuvant chemotherapy: This is given to shrink a tumor’s size before surgery or radiation therapy.
• Adjuvant chemotherapy: This is given after surgery or radiation therapy to destroy any remaining cancer cells and prevent cancer from coming back.
• Curative chemotherapy: This is given instead of surgery or radiation to eliminate all the cancerous cells in a body.
• Palliative chemotherapy: This is given to relieve symptoms or prolong a patient’s life, but eventually the cancer will be fatal. There can be several types of palliative chemotherapy for a patient.

There are a variety of ways that chemotherapy can be given. Methods are as follows:

• Oral: Chemotherapy can be given orally as a pill, capsule, or liquid.
• Intravenous (IV): Chemotherapy can be administered into a vein intravenously, through a catheter inserted in a vein, a port surgically installed in the chest, or an internal or external pump.
• Injection: Chemotherapy drugs can be given via a shot (in the arm, leg, or hip).
• Intrathecal: Chemotherapy is injected between the brain and spinal tissues.
• Intraperitoneal (IP): Chemo can be injected into the area of the body where the vital organs (stomach, intestines, liver) are located, also known as the peritoneal cavity.
• Intra-arterial (IA): Sometimes chemotherapy is injected into an artery that feeds blood to the tumor.
• Topical: Chemotherapy creams can be rubbed into the skin.

A medical oncologist will decide the most effective method for you, considering the kind of cancer you have, its location and stage. Your doctor will also consider other medications you are taking and health conditions you may have such as diabetes; arthritis; and heart, lung, or kidney disease when deciding on your treatment approach. 

Chemotherapy drugs are designed to attack fast-growing cancer cells. The problem is that there are other quick-dividing healthy cells that are inadvertently attacked by chemo. These cells include ones that line the mouth and intestines, as well as cells needed to produce hair. As a result of damage to these cells, people experience side effects such as mouth sores, nausea, and hair loss. 

Another common side effect patients experience while on chemo is fatigue, as their bodies try to generate new, healthy cells to replace the defective ones being killed off by chemo. These symptoms are often temporary and will get better or resolve completely once you have finished your chemotherapy.

Sometimes chemotherapy can affect heart function. Therefore, patients should be monitored closely by a cardiology-oncology team. This team focuses on monitoring how chemotherapy affects the heart and other organs, in addition to fighting the cancer.

Because of the fatigue associated with chemotherapy, you will need to take good care of yourself so that your body can grow new, healthy cells. Below are ways to ensure you remain in good health:

• Get extra rest during treatment.
• Ask for help from family and friends who can drive you to receive your treatments.
• You may also need help with cooking, household chores, and childcare.
• Patients may need to take time off from work for their treatments or to recover afterward.  
• If you have mouth sores or nausea, work with a Smilow nutritionist to make sure you get adequate nutrients and manage any weight loss issues.
• If you have hair loss or skin or nail discomforts, see a Yale Medicine dermatologist who specializes in cancer care (an onco-dermatologist). He or she can help manage the hair, skin, and nail-related side effects of chemotherapy.

Depending on how chemotherapy is given (intravenously, via injection or orally, for example), it can be administered at the hospital, an outpatient center, doctor’s office, or at home by a visiting nurse. You doctor will give you detailed instructions on where and when treatment will occur.

Treatment depends on your type of cancer. For example, chemotherapy may be given for one or several weeks followed by a break for several weeks. This rest period allows the body to recover from therapy and work on producing new, healthy cells. Doctors will perform imaging (X-rays, MRIs, CT scans) and blood tests to see how the tumor responded to the treatment. 

For some patients, chemotherapy may be the only treatment needed. For others, a combination of the following treatments may be needed, depending on the type, stage, and location of the cancer: surgery, radiation therapy (radiotherapy/radiosurgery) and/or immunotherapy.

Yale Medicine doctors are academic physician-scientists who work together at Yale Cancer Center located at Smilow Cancer Hospital. We lead cancer research and clinical trials to help find new ways to treat cancer. Our medical oncologists discuss each cancer case with a group of specialists at weekly meetings to review the recommended treatment plan for each patient.

Cancer patients seeking treatment from Yale Medicine doctors have many advantages. Because chemotherapy can have side effects on the skin and mouth, Smilow Cancer Hospital offers onco-dermatology services to help patients with skin, hair, and nail-related side effects from cancer treatment. We also provide access to nutritionists who can help patients manage mouth sores, nausea, and weight loss issues. In addition, our Cardio-Oncology Program provides specialty care for patients who have cancer to help with any effects chemotherapy may have on heart function.

Yale Cancer Center is a National Institutes of Health (NIH) Comprehensive Cancer Center and a center of clinical and research excellence. “Cancer patients at Yale receive the best available care for their cancer but also have the opportunity to participate in the newest cancer clinical trials of leading-edge treatments—chemotherapy, targeted therapy, and immunotherapy,” says Dr. Eder.