Physician Specialist Glossary

How Is Cancer Diagnosed?

The earlier cancer is diagnosed and treated, the better the chance of its being cured. Some types of cancer -- such as those of the skin, breast, mouth, testicles, prostate, and rectum -- may be detected by routine self-exam or other screening measures before the symptoms become serious. Most cases of cancer are detected and diagnosed after a tumor can be felt or when other symptoms develop. In a few cases, cancer is diagnosed incidentally as a result of evaluating or treating other medical conditions.

Cancer diagnosis begins with a thorough physical exam and a complete medical history. Laboratory studies of blood, urine, and stool can detect abnormalities that may indicate cancer. When a tumor is suspected, imaging tests such as X-rays, computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, and fiber-optic endoscopy examinations help doctors determine the cancer's location and size. To confirm the diagnosis of most cancers , a biopsy needs to be performed in which a tissue sample is removed from the suspected tumor and studied under a microscope to check for cancer cells.

If the diagnosis is positive (cancer is present), other tests are performed to provide specific information about the cancer. This essential follow-up phase of diagnosis is called staging. The most important thing doctors need to know is whether cancer has spread from one area of the body to another. If the initial diagnosis is negative for cancer and  symptoms persist, further tests may be needed. If the biopsy is positive for cancer, be sure to seek a confirming opinion by a doctor who specializes in cancer treatment before any treatment is started.

What Are the Treatments for Cancer?

Depending on the type and stage of cancer, treatments to eradicate the tumor or slow its growth may include some combination of surgery, radiation therapy, chemotherapy, hormone therapy or immunotherapy.