Understanding Cancer Treatment
Cancer treatment: neoadjuvant therapy, adjuvant therapy, and surgery
When a relative or close friend receives a diagnosis of cancer, he'll soon be plunging into the complex world of cancer treatment. Typically, his doctor will refer him to an oncologist, who plans a course of treatment. This may be a single process, such as chemotherapy, or more likely it will be a combination of different treatment types, such as surgery followed immediately by radiation, followed later by a course of chemo. Within each of these treatment categories, there are myriad distinctions to understand and decisions to make, which can leave you and the patient feeling overwhelmed.
To help you and him sort through the maze of cancer treatments, here's a guide to the main types and how they work.
Neoadjuvant therapy and adjuvant therapy . Sometimes oncologists prescribe chemotherapy, radiation, or other drugs, such as hormones, to shrink a tumor priorto surgery. This is known as neoadjuvant therapy. Adjuvant therapy is the term for chemotherapy or radiation given after surgery.
Various types of surgery . If the doctor identifies a tumor that's safe for removal, surgery is going to be an important part of the treatment. The oldest form of cancer treatment, surgery is still considered the best way to remove cancerous tissue, particularly when it's localized in one area of the body. The goal in surgery is to remove the entire tumor, including the cancerous cells spreading around the edge, or "margin," of the tumor.
The patient's doctor may discuss one or a number of different types of surgery:
- Laser surgery. Most people picture a scalpel when thinking about surgery, but today some surgeries are performed using lasers to cut tissue. Lasers are typically used for very precise surgeries, such as in the eye or larynx, but they can also be used to vaporize cancers in particular areas, such as the cervix or rectum. Lasers or cryosurgery (freezing) are commonly used to treat skin cancer.
- Surgery on surrounding areas. Sometimes additional surgery is performed on other areas where the cancer is spreading. Breast cancer, for example, is often treated with surgery to remove the tumor in the breast and additional surgery or biopsy to remove the lymph nodes under the arm. The surgeon may also decide to remove blood vessels close to the tumor to prevent the cancer from spreading.
- Diagnostic surgery. Some types of surgery are used to diagnose and "stage" cancer when the doctor can't see what's going on from outside the body.
Biopsies are the most common type of diagnostic surgery. Using a needle, the doctor draws a tissue sample from a tumor. Biopsies can also be done by cutting through the tissue with a knife or laser. An excisional biopsy is one that cuts out the entire tumor, while an incisional biopsy removes a small part of a larger tumor. Unlike regular surgery, biopsies are often outpatient procedures performed using local anesthesia.
Endoscopies often done in tandem with biopsies, use a flexible tube and scope to pass through the throat or colon in order to examine a potentially cancerous area without cutting through the skin. Endoscopies are also usually done on an outpatient basis.
Laparoscopies are similar to endoscopies, but they do require a small incision -- usually in the abdomen -- through which the doctor inserts the scope.
- Prophylactic surgery. This type of surgery is a proactive treatment used to prevent cancer from developing in people who are likely to develop the disease. For example, women with a strong family history of breast cancer may choose to have a prophylactic mastectomy to protect themselves.
Cancer treatment: chemotherapy
One of the most effective ways to kill off cancer cells is with toxic chemicals called chemotherapy agents, which are drugs developed to target fast-growing cells. There are many different chemotherapy drugs, and some attack a variety of types of cancer while others focus on particular cancers, such as breast cancer or lung cancer.
Chemotherapy drugs work by targeting all fast-growing cells, so they also affect rapidly dividing cells in other parts of the body, such as the hair, the mouth, and the digestive system, which is what leads to common side effects such as dry mouth and hair loss . Unlike radiation and surgery, which are site-specific, or "local," chemotherapy is considered a "systemic" treatment, since the medications travel throughout the body.
• Chemotherapy drugs. Some chemotherapy drugs, called "nonspecific," are capable of killing cancer cells during any phase of growth; others, called "specific," can kill cancer cells only during a specific phase and not while the cell is resting. Doctors often create a chemotherapy regimen by combining specific and nonspecific chemo agents for maximum effect.
When a patient's doctor chooses a drug, she also makes decisions about dosage level, frequency of dosage, and length of treatment. These decisions can affect how easy or difficult it is for the patient to tolerate his chemo regimen. The more you can find out about exactly which drugs will be used, in what dosages, and for how long, the better prepared you and he will be to cope with the side effects to come. Some chemotherapy drugs are given through an IV while others can be taken orally or by injection.
• Chemotherapy schedules. Nowadays, chemotherapy is most often performed on an outpatient basis, though if your friend or relative has to be hospitalized for surgery, the doctor may start chemo while he's still in the hospital.
Chemotherapy is usually given in cycles, with periods of treatment followed by periods of rest to let his body recover. He might receive three weeks of chemo followed by one week of rest, or one week of chemo followed by three weeks of rest. Either way, a full four weeks makes up one cycle. Sometimes a patient has to meet certain health criteria in order to go through the next round of chemotherapy. For example, the doctor may monitor his blood cell counts, and if his white or red blood cell count drops too low, the doctor may have to postpone the next round of chemo until the count rises again.
Cancer treatment: radiation and hormone therapy
Radiation therapy. Radiation can be performed after a tumor is surgically removed to catch stray cancer cells, before surgery to shrink a tumor, or as a stand-alone therapy.
There are two general kinds of radiation therapy: internal and external. Doctors usually recommend internal radiation, also called brachytherapy, when they want to target the cancer with a high dose of radiation delivered internally to a small area, such as tumors located in the breast, prostate, head, or neck. The radiation is implanted or injected in wires, "seeds," or capsules, then left in place for a period of time, either until they're removed or until they decay and become inactive. Brachytherapy is usually performed as an outpatient procedure, though sometimes doctors choose to implant a radioactive "source" at the end of surgery.
When the radiation is beamed into the body from an outside source, most often from an X-ray machine or linear accelerator, it's called external radiation. External radiation is usually given in the form of a sequence of treatments, typically five days a week for six to eight weeks. (On weekends, the patient gets a break so his body can recover.)
Radiation therapy is a rapidly improving technology, and there are many different types available.
Hormone therapy. Used most often to treat breast and prostate cancers, hormone therapy uses the body's own natural hormones to treat cancers that are affected by the hormones produced by the endocrine system. Because hormones fuel the growth of some types of cancer, cutting off or blocking the action of those hormones can stop the cancer from growing. Estrogen blockers, for example, can be very effective in treating some types of breast cancer , while blocking testosterone can be effective in preventing the growth of prostate cancer cells.