Types of Cancer
How Is Each Cancer Type Named?
Cancer is named after the part of the body where it originated. When cancer spreads, it keeps this same name. For example, if kidney cancer spreads to the lungs, it is still kidney cancer, not lung cancer. Lung cancer would be an example of a secondary tumor.
Staging is the process of determining whether cancer has spread and, if so, how far. There is more than one system used for staging cancer.
What Are the Different Types of Cancer?
Cancer is not just one disease but rather a group of diseases, all of which cause cells in the body to change and grow out of control. Cancers are classified either according to the kind of fluid or tissue from which they originate, or according to the location in the body where they first developed. In addition, some cancers are of mixed types.
The following five broad categories indicate the tissue and blood classifications of cancer:
A carcinoma is a cancer found in body tissue known as epithelial tissue that covers or lines surfaces of organs, glands, or body structures. For example, a cancer of the lining of the stomach is called a carcinoma. Many carcinomas affect organs or glands that are involved with secretion, such as breasts that produce milk. Carcinomas account for 80-90% of all cancer cases.
Types of carcinoma include:
- Basal cell carcinoma
- Squamous cell carcinoma
- Merkel cell carcinoma
A sarcoma is a malignant tumor growing from connective tissues, such as cartilage, fat, muscle, tendons, and bones. The most common sarcoma, a tumor on the bone, usually occurs in young adults. Examples of sarcoma include osteosarcoma (bone) and chondrosarcoma (cartilage).
Types of sarcoma include:
- Soft tissue sarcoma
- Ewing’s sarcoma
Lymphoma refers to a cancer that originates in the nodes or glands of the lymphatic system, whose job it is to produce white blood cells and clean body fluids, or in organs such as the brain and breast. Lymphomas are classified into two categories: Hodgkin’s lymphoma and non-Hodgkin’s lymphoma.
Types of lymphoma include:
- Hodgkin’s lymphoma
- Non-Hodgkin’s lymphoma
- Cutaneous lymphoma
Leukemia, also known as blood cancer, is a cancer of the bone marrow that keeps the marrow from producing normal red and white blood cells and platelets. White blood cells are needed to resist infection. Red blood cells are needed to prevent anemia. Platelets keep the body from easily bruising and bleeding.
Examples of leukemia include acute myelogenous leukemia, chronic myelogenous leukemia, acute lymphocytic leukemia, and chronic lymphocytic leukemia. The terms myelogenous and lymphocytic indicate the type of cells that are involved.
Types of leukemia include:
- Acute lymphocytic leukemia
- Acute myeloid leukemia
- Agnogenic myeloid leukemia
- Chronic lymphocytic leukemia
- Chronic myeloid leukemia
- Essential thrombocythemia (ET)
- Hairy cell leukemia
- Myelodysplastic syndromes (MDS)
Myeloma grows in the plasma cells of bone marrow. In some cases, the myeloma cells collect in one bone and form a single tumor, called a plasmacytoma. However, in other cases, the myeloma cells collect in many bones, forming many bone tumors. This is called multiple myeloma.
How Is Cancer Diagnosed?
There is no single test that can accurately diagnose cancer. The complete evaluation of a patient usually requires a thorough history and physical examination along with diagnostic testing. Many tests are needed to determine whether a person has cancer, or if another condition (such as an infection) is mimicking the symptoms of cancer.
Effective diagnostic testing is used to confirm or eliminate the presence of disease, monitor the disease process, and to plan for and evaluate the effectiveness of treatment. In some cases, it is necessary to repeat testing when a person’s condition has changed, if a sample collected was not of good quality, or an abnormal test result needs to be confirmed.
Diagnostic procedures for cancer may include imaging, laboratory tests (including tests for tumor markers), tumor biopsy, endoscopic examination, surgery, or genetic testing.
Cancer diagnosis methods:
- Lab tests
- Diagnostic imaging
- Endoscopic exams
- Genetic tests
- Tumor biopsies
What are the different types of lab tests used to diagnose cancer?
Clinical chemistry uses chemical processes to measure levels of chemical components in body fluids and tissues. The most common specimens used in clinical chemistry are blood and urine.
Many different tests exist to detect and measure almost any type of chemical component in blood or urine. Components may include blood glucose, electrolytes, enzymes, hormones, lipids (fats), other metabolic substances, and proteins.
The following are some of the more common laboratory tests:
- Blood tests
- Complete blood count (CBC)
- Tumor markers
Diagnostic radiology has greatly advanced in recent years with the development of new instruments and techniques that can better detect cancer and also help patients avoid surgery.
What are the different types of diagnostic imaging?
Imaging is the process of producing valuable pictures of body structures and organs. It is used to detect tumors and other abnormalities, to determine the extent of disease, and to evaluate the effectiveness of treatment. Imaging may also be used when performing biopsies and other surgical procedures. There are three types of imaging used for diagnosing cancer: transmission imaging, reflection imaging, and emission imaging. Each uses a different process.
X-rays, computed tomography scans (CT scans), and fluoroscopy are radiological examinations whose images are produced by transmission. In transmission imaging, a beam of high-energy photons is produced and passed through the body structure being examined. The beam passes very quickly through less dense types of tissue such as watery secretions, blood, and fat, leaving a darkened area on the X-ray film. Muscle and connective tissues (ligaments, tendons, and cartilage) appear gray. Bones will appear white.
- Computed tomography scan (also called a CT scan or computed axial tomography or CAT scan)
- Bone scan
- Lymphangiogram (LAG)
Reflection imaging refers to the type of imaging produced by sending high-frequency sounds to the body part or organ being studied. These sound waves “bounce” off of the various types of body tissues and structures at varying speeds, depending on the density of the tissues present. The bounced sound waves are sent to a computer that analyzes the sound waves and produces a visual image of the body part or structure.
Emission imaging occurs when tiny nuclear particles or magnetic energy are detected by a scanner and analyzed by computer to produce an image of the body structure or organ being examined. Nuclear medicine uses emission of nuclear particles from nuclear substances introduced into the body specifically for the examination. Magnetic resonance imaging (MRI) uses radio waves with a machine that creates a strong magnetic field that in turn causes cells to emit their own radio frequencies.
- Magnetic resonance imaging (MRI)
What are the different types of endoscopic examinations used to diagnose cancer?
Types of endoscopies include:
- Cystoscopy (also called cystourethroscopy)
- Endoscopic retrograde cholangiopancreatography (ERCP)
- Esophagogastroduodenoscopy (also called EGD or upper endoscopy)
What are the different types of tumor biopsies used to diagnose cancer?
A biopsy is a procedure performed to remove tissue or cells from the body for examination under a microscope. Some biopsies can be performed in a physician’s office, while others need to be done in a hospital setting. In addition, some biopsies require use of an anesthetic to numb the area, while others do not require any sedation.
Biopsies are usually performed to determine whether a tumor is malignant (cancerous) or to determine the cause of an unexplained infection or inflammation.
The following are the most common types of biopsies:
- Endoscopic biopsy
- Bone marrow biopsy
- Excisional or incisional biopsy
- Fine needle aspiration biopsy
- Punch biopsy
- Shave biopsy
- Skin biopsy