What is the difference between a cyst and a tumor?
In this article, learn about the differences between cysts and tumors. We explore the most common types and describe the conditions that cause them.
Cysts vs. tumors
A cyst is a sac of tissue that can form anywhere on the body.
A cyst is a sac of tissue that is filled with another substance, such as air or fluid. Tumors are solid masses of tissue.
Cysts can form anywhere on the body, including on the bones and soft tissues.
Most cysts are noncancerous, although there are some exceptions. Cysts can feel tender to the touch, and a person may be able to move one easily.
Tumors can also grow almost anywhere in the body. They tend to grow quickly and are usually firm to the touch.
It is possible to have cysts and tumors in the same organ.
Conditions that cause cysts
Some of the many types of cyst include:
- Breast cysts: These are fluid-filled sacs that a person can easily move under the skin. A person with many of these cysts has a condition called fibrocystic breasts.
- Epidermoid cysts: These cysts develop on the top layer of skin, called the epidermis. They can form on the neck, chest, upper back, and scrotum.
- Hepatic cysts: Hepatic cysts grow in the liver.
- Pilar cysts: These form in cells at the bottom of hair follicles. The thick fluid inside the cysts often contains keratin, a hard substance that skin cells produce. Pilar cysts usually develop on the scalp.
- Renal cysts: These grow in the kidneys.
- Ovarian cysts: These form on the ovaries, usually around the time of ovulation. They are harmless and often cause no symptoms. They sometimes lead to pelvic pain, back pain, and bloating.
There are many other, less common types of cysts.
Conditions that cause tumors
Lipomas are fat cell tumors that often develop in people over 40.
Tumors may be either benign (noncancerous) or malignant (cancerous). Benign tumors usually grow in one place and do not spread.
Malignant tumors develop in one area of the body, then spread to others. Both benign and malignant tumors vary in size.
Some tumor types include:
- Adenomas: These are made of glandular epithelial tissue, which covers the organs and glands. Examples of these tumors include colon polyps, bile duct adenomas, and hepatic adenomas. They can be cancerous but are usually benign.
- Fibroids: These benign tumors grow on the connective or fibrous tissues. They most commonly develop in, on, or around the uterus.
- Lipomas: These fat cell tumors often form in people over 40. They are usually soft and located just under the skin. They are almost always benign.
- Malignant tumors: These can develop anywhere in the body. Sarcomas, for example, develop from connective tissue such as bone marrow. Carcinomas, another common type of malignant tumor, grow from epithelial cells in the colon, liver, or prostate.
Tumors can grow so large that they push into organs, causing pain and other symptoms. A surgeon will usually remove large tumors.
All cancerous tumors are usually removed unless they are impossible to reach or located so close to a vital organ that surgical removal may cause harm.
A doctor may use an ultrasound to examine a cyst or tumor in more detail.
A doctor can use several diagnostic methods to distinguish between a tumor and a cyst. They will start by taking a medical history, then ask when symptoms began and when they are most prominent.
The timing of symptoms is important. For example, cysts may become more noticeable around menstruation, due to hormonal fluctuations.
A doctor will also examine the cyst or tumor, if possible. They will consider its location, color, how it feels, and whether any material is draining from it.
A doctor may use an ultrasound to examine a cyst or tumor located deep within the body. Ultrasound imaging can often show whether a lump is hollow, fluid-filled, or a collection of cells.
In some cases, a doctor may request a biopsy, which involves removing the lump or cells from it. The biopsy will be sent to a laboratory for testing.
When to see a doctor
While not all cysts and tumors require treatment, a person should have a lump examined if it appears to be growing quickly.
Other potentially dangerous symptoms include:
- bleeding from area
- pain or tenderness
- inhibited movement
- an inability to perform daily activities due to the tumor or cyst
Tumors and cysts can be a cause for concern, although some are harmless. Cysts are often filled with air or with another type of cell, forming a fluid. Tumors are masses of one type of cell.
Anyone concerned by a lump or growth should see a doctor. They can perform tests, diagnose the lump, and determine whether a person needs treatment.