What Are the 5 Most Common Types of Cancer?

What is cancer?

Cancer is a term used to describe a group of related diseases wherein abnormal cells begin to continually divide and spread into surrounding tissues. Cancer can develop anywhere in the body. Normally, cells in the body grow and divide as needed; for example, when a cell gets old, becomes damaged, or dies, a new cell takes its place. Cancer disturbs this process: cells become more and more abnormal, damaged cells don’t die, and uncontrolled abnormal cell growth occurs.

Depending on the type of cancer, a solid tumor or mass of tissue may develop. Cancerous tumors are malignant, meaning that they spread and invade nearby tissue. Cancerous cells can also travel to other parts of the body via the lymphatic system or bloodstream and form a new tumor.

Not all tumors are cancer. Some are benign tumors that do not spread or invade other tissues. Benign tumors are generally not life-threatening, except for those that develop in the brain.

Cancer is the second-leading cause of death in the world. Oftentimes, if cancer is detected and treated early, the disease can be slowed or stopped.

The five most common types of cancer include breast cancer, lung cancer, prostate cancer, colorectal cancer, and skin cancer.

1. Breast cancer develops in the breast(s) and, at later stages, can spread throughout the lymphatic system, affecting other parts of the body. Breast cancer is the most common type of cancer in women. Women age 55 and older account for 66% of all cases. Symptoms of breast cancer include, but are not limited to, a lump in the breast; changes in the size, shape, or appearance of the breast; bloody nipple discharge; inverted nipple; swollen lymph node(s) in the neck or armpit; and breast pain. Breast cancer can be found by self-exam, mammography, biopsy, or ultrasound. Regular self-examination of the breasts is important, and yearly mammograms are advised for women over 40. Recent advances in treatments have greatly improved survival rates for this disease, particularly if it is detected early.
2. Lung cancer develops in the lungs. It is the leading cause of cancer deaths worldwide. Individuals who smoke are at the greatest risk for developing lung cancer, but it can also develop in individuals who never smoked. Even after years of smoking, quitting the habit can significantly reduce the risk of developing lung cancer. Symptoms of lung cancer include, but are not limited to, a persistent cough, coughing up blood, shortness of breath, wheezing, chest pain, and recurrent or treatment-resistant infections. Lung cancer is diagnosed through the use of imaging tests and biopsy. Preventative low-dose CAT scan screenings may be beneficial to those who have smoked for many years, are over 55, or are at a high risk for lung cancer for other reasons.
3. Prostate cancer develops in the prostate gland (a walnut sized gland located just below the bladder and surrounding the top of the urethra in males). Prostate cancer is the most commonly diagnosed cancer in men over age 50. Symptoms of prostate cancer include, but are not limited to, frequent urination, incontinence, pain, blood in the urine, and fatigue. Prostate cancer is diagnosed with the use of digital rectal exam, lab tests for elevated levels of prostate specific antigen (PSA), and biopsy. Early detection greatly improves the survival of prostate cancer. Regular prostate screenings are advised for men after the age of 55.
4. Colorectal cancer occurs in the large intestine (colon) or rectum. Colon and rectal cancers are grouped together as they have many features in common. Although colorectal cancer can develop at any age, it typically affects older adults. It usually begins as a growth (polyp) on the inner lining of the colon or rectum. However, not all polyps will become cancerous. Symptoms of colorectal cancer include, but are not limited to, a persistent change in bowel habits, including diarrhea or constipation; rectal bleeding; blood in the stool; abdominal or pelvic pain; unexplained weight loss; vomiting; unexplained anemia; and fatigue. Diagnosis is confirmed via colonoscopy and biopsy. To prevent colorectal cancer, screening is important. Recommended screenings vary depending on age and individual risk factors. The American Cancer Society recommends screenings starting at age 45.
5. Skin cancer is the fifth most common type of cancer diagnosed in the United States. Early detection is important as skin cancer can spread and become life-threatening if not treated. Not all skin cancers share the same symptoms, but changes in the skin can be a warning sign. General symptoms to watch for include, but are not limited to, a new mark, mole, sore or lesion that doesn’t go away; asymmetry of a mole (the two sides look different); lesion with unclear or ragged borders, an unusual color, or larger than the size of a pencil eraser (¼ inch); or visible changes in a mole or sore.
   
   Diagnosis of skin cancer typically involves a physical examination and a biopsy of the affected area. Specific treatment varies depending on the type of skin cancer and its severity. The best way to reduce the risk of skin cancer is by limiting or avoiding exposure to UV radiation. Wearing sunglasses, a hat, and sunscreen while exposed to the sun and avoiding the use of tanning beds can help reduce the risk of the disease. Checking the skin regularly for suspicious discolorations, lesions, or markings is also important.