Difference between Benign and Malignant tumors

It’s never easy to be diagnosed with either one, but knowing the difference is crucial.


Benign vs Malignant tumors
Illustration of a benign (top) and malignant (bottom) tumor

A mass of cells that doesn’t have the ability to spread and invade surrounding tissue (metastasize) is non-cancerous and is classified as a benign tumor. This type of tumor is generally slow growing, and the tumor cells usually look normal. Benign tumors are usually surrounded by a fibrous cover of connective tissue. Moles are typical examples of benign tumors.

Benign tumors may not invade surrounding tissues, but they can still pose a health problem. When a benign tumor grows it can create a “mass effect” that can cause tissues to compress and may lead to nerve and organ damage, tissue death, and blood loss to a particular part of the body.

Most benign tumors are non-life threatening, but there are some that have the potential to become cancerous. This can be brought about through what is called tumor progression. Some benign tumors are surgically removed because of this and due to other health problems they may cause.

Benign tumors may not show any symptoms. If they do, specific symptoms will come up depending on the tissue type and where the tumor is in the body.

Malignant tumors are not only capable of growing, they have the capability to invade nearby tissues. They can quickly multiply and spread to distant tissues and other parts of the body. Malignant cells lack chemical adhesion that would fix them to where they originated. Most importantly, malignant tumors are cancerous.

With varying sizes and shapes, malignant tumors grow in an abnormal fashion and can go out of control and spread to blood vessels or lymphatic vessels. They disrupt normal body functions and can become life-threatening.

Benign vs Malignant tumor

So what’s the difference between a benign and a malignant tumor?

Benign tumors are not cancerous and are not capable of spreading to nearby tissue or other organs. A malignant tumor is cancerous. It can grow rapidly and can invade surrounding tissue and other parts of the body.

Benign tumors are enclosed in a connective tissue that prevent it from spreading. Malignant tumors do not have connective tissues, thus they can “travel” to other body organs.

Usually non- life threatening, benign tumors grow at a slow pace and can be surgically removed. Malignant tumors grow and spread rapidly and uncontrollably disrupting normal body functions, and can be life-threatening.

Comparison chart

Benign tumors Malignant tumors
Non-cancerous Definitely cancerous
Not capable of growing and spreading Grows and spreads
Covered in connective tissue Not enclosed in connective issue


Check out this short clip highlighting the difference between these 2 types of tumors