Glossary

Abnormal growth

Abnormal growths could be malignant (cancer), pre-cancerous (it could become cancer) or benign (not cancer).

Stage

Stage is used to define how far a cancer has progressed, based on tumor size and metastasis. Stage 1 is early and Stage 4 is the most advanced.

Metastasis

Metastasis describes the transference of cancerous cells to other parts of the body. Stage 4 cancer is “metastatic,” meaning that the process of metastasis has occurred and the cancer has spread from the original site.

Treatment line

First line treatment is the first type of treatment that is given to a cancer patient. Second line treatment is the treatment that is given if the first line treatment was not effective. There are also third line treatments and beyond. There are treatment protocols that are used to decide what first line and second line treatments should be prescribed.

Biopsy

A biopsy is when a sample of cells is taken from the body. Testing can then be conducted on the sample to establish whether cancer is present, for example to diagnose a patient or to understand if it has spread throughout the body.

PET Scan

Positron emission tomography (PET) scans produce 3-D images of how the inside of the body is functioning. They can be combined with CT scans or MRI scans so that doctors can have a view of both the structures as well as the chemical functioning inside of the body.

CT Scan

Computerized tomography (CT) scan, sometimes called a CAT scan, is a type of X-ray and computer processing that provides more detailed information than a regular X-ray. CT scans are used for diagnosis and monitoring. Patients are positioned on a bed that is moved into a scanner in order to have this test.

Sputum cytology

Sputum is saliva and mucus that can be produced when you have a cough. Sputum cytology is when this substance is examined to look for the presence of lung cancer cells.

MRI

Magnetic resonance imaging (MRI) is a non-invasive scan that uses magnets and radio waves to help visualize the structures inside of the body. Patients are positioned on a bed that is moved into a scanner in order to have this test

Tumor markers

Tumor markers are substances within or made by cancer cells or by the body in response to cancer. There are many different types of tumor markers and they can be used in the clinic in different ways to provide information about a cancer condition, such as response to treatment. Tumor markers are measured by taking a sample of tissue or a bodily fluid, such as blood.

Mammogram

A mammogram is an X-Ray taken of breast tissue that is used for the detection and screening of breast cancer.

Ultrasound

Ultrasound is a type of imaging that makes use of high-frequency sound waves. The waves are directed at a body part and then the echo is detected and can be displayed as an image on a computer screen, allowing for visualization of the inside of the body. Ultrasound can be used for cancer detection as well as monitoring.

CAR-T cell therapy

This is a form of immunotherapy in which a patient’s T cells (cells that are part of the immune system) are collected from a patient’s blood and modified in a laboratory so that they produce receptors on their surface called chimeric antigen receptors (CARs), which are able to recognize specific molecules on tumor cells called antigens. The modified T cells are infused back into the patient’s blood. Guided by their engineered receptors, T cells are then able to recognize and kill cancer cells that harbor the antigen on their surfaces.

Immunotherapy

Immunotherapy is a form of treatment that boosts the body’s own natural defenses (so called immune system) to fight and eliminate diseases such as cancer. The role of the immune system is to recognize and fight abnormal cells and other invaders such as germs. It should also be able to recognize and destroy cancerous cells, but it doesn’t always do so. Cancer cells have the ability to hide from the immune system or can inhibit it.Immunotherapies work by either stimulating the immune system so that it can work better to find and attack cancer cells or by making cancer cells more recognizable for the immune system. Various types of immunotherapies are used to treat cancer, such as immune checkpoint inhibitors, monoclonal antibodies, T-cell transfer therapy, cancer vaccines and immune system modulators.

Chemotherapy

Chemotherapy is the combination of one or multiple drugs that can be used to treat many types of cancer. Chemotherapy drugs interfere with cancer cells’ ability to divide and proliferate. The treatment usually lasts between one day and a few weeks, depending on the type and stage of cancer. Chemotherapy can be used to destroy cancerous cells, to prolong life by controlling and preventing cancerous cells from spreading to other parts of the body, or to ease pain by shrinking the size of a tumor.

Radiation therapy

Radiation therapy, or radiotherapy, is a treatment that uses waves of radiation to kill or control the proliferation of cancer cells. The treatment can be used alone or in combination with other therapies, such as chemotherapy. Radiation damages both cancerous and surrounding healthy cells in the targeted area. However, normal cells can often repair most of the damage caused by radiation. Radiotherapy used to treat cancer usually lasts between 1 to 7 weeks.

Hormone therapy

Some cancers, such as some breast and prostate cancers, are hormone-dependent or hormone-sensitive, meaning that they need hormones to grow or develop. Hormone therapy uses medicines to block or lower the amount of hormones in the body, thus blocking cancerous cells’ growth. Hormone therapy can be used to reduce the size of a tumor before surgery or radiation therapy. This is called neo-adjuvant therapy. In other cases, it is used to lower the risk that cancer will come back. This is called adjuvant therapy.

Surgery

Surgery is the removal of cancerous tissue. It is often used in conjunction with chemotherapy or radiotherapy to remove or reduce the size of the cancer as well as reduce the chance that it will reoccur.

Immune checkpoint inhibitors

Immune checkpoint inhibitors are a type of immunotherapy. The immune system is usually able to recognize tumor cells and other intruders like viruses and bacteria and attacks them. However, tumor cells are able to hide from the immune system by stimulating the immune system’s brakes or so-called immune checkpoints. Immune checkpoint inhibitors drugs are designed to release the brakes turned off by tumor cells so that the immune system can recognize and kill tumor cells.

Therapeutic antibodies

Antibodies are proteins produced by the immune system that bind to specific markers on cells or tissues. A monoclonal antibody is designed so that it binds to only one marker. In cancer treatment, monoclonal antibodies are biologic therapies that can be used in various ways. For example, they can help the immune system detect cancer cells, trigger an immune response that destroys the membrane of a cancer cell, block cancer cell growth, trigger cancer cells to self-destroy or deliver radio-and chemotherapies directly to cancer cells, hence minimizing the toxic effect on healthy cells.

Objective response rate (ORR)

Objective response rate is the proportion of patients in a clinical trial whose tumor size has significantly shrunk or disappeared after treatment.
ORR is usually the sum of:

• Complete responses (CRs): patients who don’t show any detectable evidence of a tumor over a specific period of time
• Partial responses (PRs): patients who show a decrease in their tumor size over a specific period of time.

An improved ORR is a tangible indication that a drug is working.

Overall survival (OS)

Measures how long from the start of a treatment patients live compared to patients who are in a control group (e.g. receiving either an approved drug or a placebo). If a clinical trial demonstrates improved OS, this is evidence that the experimental drug is prolonging patients’ lives. OS is considered to be the “gold standard” for determining the clinical benefits of an experimental cancer drug, as it requires a larger number of patients and longer follow-up time to show compared to other clinical trial endpoints, and it can be easily and precisely measured.

Duration of response (DoR)

Duration of response is the amount of time that a tumor continues to respond to treatment without the cancer growing or spreading.

Stable Disease (SD)

Stable disease is defined when the tumor is neither decreasing or increasing in extent or severity.

Progression-free survival (PFS)

Measures how long a patient survives without the disease worsening. PFS results are usually available earlier than OS and give an indication about the impact of a drug on disease control and stabilization. PFS is generally used to study serious diseases that are unlikely to be completely cured.

Event-free survival (EFS):

Time from therapy randomization before one of the following events occurs: disease progression, death or treatment discontinuation.

Hazard Ratio

Measures how often a particular event happens in a group compared to how often it happens in another group. In clinical trials for cancer treatment, it usually compares survival at a specific time point in a group of patients that received the experimental drug in comparison to a control group that received another treatment or a placebo. A hazard ratio of one means that there is no difference in survival between the two groups. A hazard ratio greater than 1 suggests an increased risk, and a hazard ratio below 1 suggests a smaller risk. For example, a hazard ratio of 0.75 for an overall survival endpoint, means there is a 25% lower risk of death in the experimental group as compared to the control group.

Control Arm

The control arm is the group of study participants that is not given the experimental intervention being studied. Instead, it receives an intervention that is considered effective (the standard treatment), a placebo, or no intervention. Outcomes in the control arm are compared with those in the experimental arm to determine any differences, for example in safety and effectiveness.

Food and Drug Administration (FDA)

A United States federal agency responsible for protecting and promoting public health through the control and supervision of human and veterinary drugs, biological products, medical devices, food products, cosmetics and products that emit radiation. The FDA regulates the conduct and approval of clinical trials. It works to protect participants and that makes sure participants receive reliable information before deciding whether to join a clinical trial. Additionally, the FDA has set up regulations and guidelines for clinical research to protect participants from unreasonable risks. The FDA staff inspect clinical study sites to protect the rights of the patients and to verify the quality and integrity of research data.

Accelerated Approval

An official process initiated by the FDA in 1992 to allow faster approval of life-saving drugs that fill an unmet medical need. The approval is based on a surrogate endpoint, (e.g. decrease in tumor size) that is faster to measure than a clinical endpoint (e.g. overall survival) and that predicts clinical benefit. Drugs approved under the FDA Accelerated Approval program still need to be tested in clinical trials using endpoints that confirm the anticipated clinical benefits. If the confirmatory trial confirms the clinical benefit of the drug, the FDA grants traditional approval for the drug, however if the confirmatory trial does not show that the drug provides clinical benefit, the FDA can remove the drug from the market.

Breakthrough Therapy

A designation granted by the FDA to a drug that treats a serious or life-threatening condition and for which preliminary clinical evidence indicates that the drug may demonstrate substantial improvement on a clinically significant endpoint over existing therapies.

Fast Track

A process designed to facilitate the development and accelerate the review of experimental drugs that treat serious conditions and fill an unmet medical need. The company developing the drug can initiate a fast track request at any time during the drug development. The FDA has then a maximum of sixty days to review the request and make a decision.

Priority Review

An FDA program to expedite the review process of drugs that are expected to have a particularly significant impact on the treatment of a serious disease, such as providing improvements in safety and efficacy over existing therapies. To be considered for Priority Review, a drug must have shown clinical benefit in clinical trials. A Priority Review designation means the FDA will review and evaluate the drug application within 6 months instead of 10 months under standard review.

Endpoint

Clinical endpoints are events or primary outcomes that can be measured objectively to determine whether an experimental drug is beneficial. Endpoints are usually listed in the study objectives. E.g. survival, improvements in quality of life, relief of symptoms, decreased pain, or absence of disease. Surrogate endpoints are substitutes for clinical endpoints and are used in trials where the use of a clinical endpoint might not be possible or practical (e.g. in the case a drug benefit would take many years to measure). Surrogate endpoints do not represent direct clinical benefit, but predict clinical outcomes. E.g. Tumor shrinkage can be used as a surrogate endpoint to predict longer survival in clinical trials for cancer treatment.

Quality of Life (QOL)

Health related quality of life is now commonly used as an endpoint in clinical trials, in particular in diseases with a poor prognosis such as metastatic cancer, where a treatment only offers a minimal gain in survival and quality of life may be of major concern. It measures the impact of a treatment on pain or other symptoms related to a condition. Quality of Life is a key patient-reported outcome that assesses how an intervention made a patient feel and the effect the intervention had on a patient’s life. Because many cancer treatments come with serious side effects, drugs with the potential to improve Quality of Life are offering substantial benefits over existing treatments.

Placebo

Some trials use a placebo, a substance without therapeutic value (such as a sugar pill), as a way to compare the effect of the study drug against what happens when patients do not receive an active medication. However, many studies use an active control where one group of patients receives the standard of care treatment and this group is compared to a group receiving the novel treatment. For example, most cancer studies use active control design.

Expanded Access

Expanded access programs, sometimes referred to as compassionate use programs, are when a company that has developed a new treatment and has completed clinical studies makes the treatment available to selected patients before it is approved by regulators to be marketed and sold. These programs exist outside of clinical trial settings so patients who are not eligible for trials or who have already completed a trial are able to use or continue to use the treatment (sometimes called an open label extension). The requirements for expanded access differ by geography, but usually these programs are limited to patients who are very ill or suffer from a long-term condition and do not have other treatment options.

ASCO Cancer.Net Cancer Terms

NCI Dictionary of Cancer Terms

American Cancer Society Glossary

NCI Fact Sheets

NCBI Dictionary of Cancer Terms