Cancer is defined as a class of diseases where malignant or abnormal cells divide uncontrollably and form lumps or masses known as tumors. Tumors can grow and impact circulatory, digestive and nervous systems, and can release hormones that can affect body functions. In cancerous tumors, cells can break off the tumors, or metastasize, to invade and grow in different parts of the body.

Cancer is defined by the area of the body it originates in. The main categories of cancer are:

  • Carcinoma—affects the skin, lungs, breasts, pancreas, and other organs and gland
  • Sarcoma—affects bone, muscle, fat, blood vessels, cartilage, or other soft or connective tissues of the body
  • Melanoma—affects cells that make skin pigment
  • Lymphoma—affects lymphocytes
  • Leukemia—affects the blood

Some cancers may have symptoms that are mistaken as less serious conditions like the flu. Others may not show symptoms in the early stages. When present, here are some of the symptoms:

  • Fatigue
  • Unexplained weight loss/gain
  • Fever
  • Pain that does not go away
  • Loss of appetite
  • Nausea, vomiting
  • Rashes, redness, tenderness or swelling
  • Blood in the stool, urine, semen or sputum
  • Persistent cough or hoarseness
  • Difficulty emptying the bowel or bladder

Cancer can be detected when there is a noticeable lump—a tumor—felt through routine self-examination. In other cases, it can be diagnosed through a doctor physical or lab work like blood, urine, and stool samples. A lymph node or bone biopsy, computed tomography (CT) scan, fluorescence in situ hybridization test, or CEA test can also help medical professionals detect cancer.

Your healthcare provider will help you chart the best treatment course.