Adjuvant therapy for cancer
Adjuvant therapy for cancer refers to additional treatments given after the primary treatment to enhance the chances of eliminating all cancer cells. This approach is commonly utilized for various cancers, including those of the breast, colon, kidney, ovary, and testicle, especially after surgery has removed or destroyed the main tumor. The therapy aims to prevent potential recurrence of cancer, as microscopic cancer cells may remain undetected in the body even in early stages.
Factors influencing the decision to pursue adjuvant therapy include patient age, tumor size, and whether cancer has spread to lymph nodes. Treatment options can include chemotherapy, radiation, hormonal therapy, targeted therapy, and immunotherapy, either alone or in combination. While adjuvant chemotherapy typically lasts for three to six months and may have side effects like hair loss and nausea, hormone therapies such as tamoxifen are also used to reduce recurrence risk, particularly in hormone receptor-positive breast cancer. Regular follow-up appointments after treatment are essential for monitoring any signs of cancer recurrence. Ultimately, the goal of adjuvant therapy is to improve survival rates and increase the duration of disease-free intervals for cancer patients.
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Adjuvant therapy for cancer
DEFINITION: An adjuvant therapy is any treatment given after the primary treatment to increase the likelihood of killing all cancer cells.
Cancers treated: Many types, including cancers of the breast, colon, kidney, ovary, and testicle
Why performed: After the primary treatment removes or kills a detected primary tumor, additional cancerous cells or microtumors may still be present in the body. Adjuvant therapy may be administered to help prevent the recurrence of cancer after the is removed. Generally, the larger the primary tumor size at detection, the larger the probability that residual cancer cells may be left behind following surgery. Cancer cells can break away from the primary tumor and even when the disease is in an early stage, and they exist in a form too small to detect by radiological or laboratory testing.
Patient preparation: In deciding whether to undergo adjuvant therapy, a number of prognostic factors enter into the determination, such as patient age, size of the primary tumor, spread to lymph nodes, and microscopic appearance of the cancer cells. Doctors consider these factors and others to estimate the likelihood of recurrence. The higher the risk for recurrence, the greater the motivation to pursue adjuvant therapy options. Local adjuvant radiation treatment typically commences about three to six weeks following the primary treatment. If a combination of and radiotherapy as adjuvant therapy is chosen, then usually chemotherapy is received first, followed by radiation, although they may be administered simultaneously in some cases. It is not known how effective adjuvant therapy may be if started later than six weeks following primary therapy.
Steps of the procedure: The term “adjuvant therapy” actually encompasses many different treatment forms, including chemotherapy, radiation, hormonal therapy, targeted therapy, immunotherapy, or some combination thereof. Adjuvant therapy can be either systemic or local. Chemotherapy, for instance, is given by mouth or injected into the bloodstream. Adjuvant chemotherapy is administered in cycles of treatment followed by recovery and typically lasts for three to six months. Side effects from adjuvant therapy such as chemotherapy or radiation may be experienced. For example, the effects of adjuvant chemotherapy may include loss of hair, loss of appetite, vomiting, diarrhea, mouth sores, psychological distress, and some loss of cognitive brain function. Medications are available to help control vomiting and nausea induced by chemotherapy. Researchers at the University of Rochester have reported that treatment with modafinil (Provigil) can alleviate the cognitive symptoms of the so-called chemo brain experienced in certain cancer treatment regimens. Various medications help with nausea. Longer-term side effects may include infertility.
Another example of adjuvant therapy is hormone adjuvant therapy to treat breast cancer. Hormone adjuvant therapy is used on breast cancer cells that have been found to be estrogen or progesterone receptor-positive. Some standard hormone therapies include the synthetic hormone tamoxifen and aromatase inhibitors. Tamoxifen as an adjuvant therapy has been found to decrease the chance of recurrence in women with early-stage hormone receptor-positive breast cancer. It is also used to treat women who are at risk of one day developing breast cancer. Aromatase inhibitors are used as adjuvants to reduce the levels of estrogen in postmenopausal women; they include anastrozole (Arimidex), exemestane (Aromasin), and letrozole (Femara). These drugs are not to be used by premenopausal women. Combination adjuvant therapies comprising hormone treatment together with chemotherapy are also available for some patients.
Adjuvant therapy has also increased the survival rate of patients with Non-Small Cell Lung Cancer (NSCLC). Immunotherapies, as well as treatment with osimertinib, a target therapy for specific types of NSCLC, have led to improved patient outcomes. Adjuvant drug therapies have also been developed for colorectal and gastric cancers, slowing cancer progression.
After the procedure: It is advised that patients undergo regular checkups following adjuvant therapy to monitor any cancer recurrence. Hormone adjuvant therapy, such as used to treat some forms of breast cancer, involves longer-term procedures, with five-year regimens recommended.
Risks: The risks associated with different forms of adjuvant therapy are similar to the risks of corresponding primary treatments with chemotherapy, radiotherapy, or hormone therapy. The main risk of declining to participate in adjuvant therapy is the possibility of cancer cells spreading undetected to other parts of the body. While patients with invasive cancers are often urged to consider undergoing adjuvant therapy, other options are available. Patients who turn down the option of adjuvant therapy are advised to participate in regular follow-up clinical examinations to facilitate the detection of new tumors. This alternative is often referred to as “watchful waiting.” Some of the side effects of hormone adjuvant therapy mimic the symptoms of menopause, such as hot flashes and an increased risk for the development of osteoporosis.
Results: The goal of adjuvant therapy is to make primary treatment more effective and result in years of disease-free survival. Successful adjuvant therapy is marked by a lack of detectable tumor recurrence or metastasis formation in the months and years following primary therapy. Patients receiving adjuvant therapy for multiple types of cancer show a significant increase in five-year overall survival rates.
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