Benign vs Malignant Tumors | Oncology | JAMA Oncology | JAMA Network
[Skip to Navigation]
Views 72,781
Citations 0
JAMA Oncology Patient Page
July 30, 2020

Benign vs Malignant Tumors

Author Affiliations
  • 1London North West University Healthcare NHS Trust, London, United Kingdom
JAMA Oncol. 2020;6(9):1488. doi:10.1001/jamaoncol.2020.2592

What Is a Tumor?

A tumor (also called neoplasm) is an abnormal mass of cells in the body. It is caused by cells dividing more than normal or not dying when they should. Tumors can be classified as benign or malignant.

Benign Tumors

Benign tumors are those that stay in their primary location without invading other sites of the body. They do not spread to local structures or to distant parts of the body. Benign tumors tend to grow slowly and have distinct borders.

Benign tumors are not usually problematic. However, they can become large and compress structures nearby, causing pain or other medical complications. For example, a large benign lung tumor could compress the trachea (windpipe) and cause difficulty in breathing. This would warrant urgent surgical removal. Benign tumors are unlikely to recur once removed. Common examples of benign tumors are fibroids in the uterus and lipomas in the skin.

Specific types of benign tumors can turn into malignant tumors. These are monitored closely and may require surgical removal. For example, colon polyps (another name for an abnormal mass of cells) can become malignant and are therefore usually surgically removed.

Malignant Tumors

Malignant tumors have cells that grow uncontrollably and spread locally and/or to distant sites. Malignant tumors are cancerous (ie, they invade other sites). They spread to distant sites via the bloodstream or the lymphatic system. This spread is called metastasis. Metastasis can occur anywhere in the body and most commonly is found in the liver, lungs, brain, and bone.

Malignant tumors can spread rapidly and require treatment to avoid spread. If they are caught early, treatment is likely to be surgery with possible chemotherapy or radiotherapy. If the cancer has spread, the treatment is likely to be systemic, such as chemotherapy or immunotherapy.

Box Section Ref ID
Section Editor: Howard (Jack) West, MD.
The JAMA Oncology Patient Page is a public service of JAMA Oncology. The information and recommendations appearing on this page are appropriate in most instances, but they are not a substitute for medical diagnosis. For specific information concerning your personal medical condition, JAMA Oncology suggests that you consult your physician. This page may be photocopied noncommercially by physicians and other health care professionals to share with patients. To purchase bulk reprints, email reprints@jamanetwork.com.
Back to top
Article Information

Published Online: July 30, 2020. doi:10.1001/jamaoncol.2020.2592

Conflict of Interest Disclosures: None reported.

Limit 200 characters
Limit 25 characters
Conflicts of Interest Disclosure

Identify all potential conflicts of interest that might be relevant to your comment.

Conflicts of interest comprise financial interests, activities, and relationships within the past 3 years including but not limited to employment, affiliation, grants or funding, consultancies, honoraria or payment, speaker's bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued.

Err on the side of full disclosure.

If you have no conflicts of interest, check "No potential conflicts of interest" in the box below. The information will be posted with your response.

Not all submitted comments are published. Please see our commenting policy for details.

Limit 140 characters
Limit 3600 characters or approximately 600 words
    ×