Key takeaways
- Cysts and tumors are both types of lumps commonly found in the body. While they can be similar in appearance, you can tell apart with a few key characteristics.
- Cysts are typically benign and are filled with fluid, air, or other material, which can be drained or removed. They can feel tender to the touch and can move around under the skin.
- Tumors can be either benign or malignant and are often made up of a solid area of tissue. They typically feel firm and hard. If your tumor is benign, it won’t require treatment, but if it is malignant, it will need to be surgically moved.
Finding a lump under your skin can be alarming, but most of the time, it’s harmless. If it’s a cyst, it is a small sac filled with air, fluid, or other material.
A tumor refers to any unusual area of extra tissue. Benign tumors tend to stay in one place, while malignant tumors grow and may cause new tumors to develop in other parts of your body.
Both cysts and tumors can appear in your skin, tissue, organs, and bones. It’s also possible to have both, such as ovarian cysts and ovarian tumors.
If you’re concerned, your doctor can help you determine what you have and whether it is serious.
In most cases, you can’t tell the difference between a cyst and a tumor just by looking at them.
However, the following chart summarizes a few things you can watch for to see whether it’s more likely to be a cyst or a tumor.
Keep in mind that these aren’t strict rules, and sometimes a cyst and a tumor can have similar characteristics. In addition, these signs apply to superficial tumors and not to internal tumors in your organs. If you see or feel anything you’re concerned about, it’s best to see your doctor.
| Characteristic | Cyst | Tumor |
|---|---|---|
| fast-growing | ✓ | |
| red and swollen | ✓ | |
| blackhead in center | ✓ | |
| white, yellow, or green discharge | ✓ | |
| firm | ✓ | |
| tender | ✓ | |
| able to move around under skin | ✓ |
Tumors can sometimes grow large enough that they put pressure on surrounding tissues. Depending on where your lump is located, you may experience additional symptoms, such as difficulty breathing, moving your joints, eating, or controlling your bladder.
If you notice a lump accompanied by unusual symptoms, even if they don’t seem related, contact your doctor as soon as possible.
Tumors are the result of abnormal cell growth. Usually, the cells in your body grow and divide to form new cells whenever your body needs them. When older cells die, they’re replaced by new ones.
Tumors form when this process breaks down. Old, damaged cells survive when they should die, and new cells form when your body doesn’t need them. When these extra cells keep dividing, they may form a tumor.
Malignant tumors are caused by cancer and can spread to nearby tissue. As cancerous tumors grow, cancer cells can break off and travel throughout the body, forming new tumors.
However, some tumors are benign, which means they form in only one spot without spreading to surrounding tissue. Types of benign tumors include:
Learn more: Benign tumors.
There are many types of cysts with various causes. These include:
- Epidermoid cysts:These develop when hair follicles get clogged and skin cells accumulate underneath.
- Sebaceous cysts: These develop if the sebaceous gland becomes blocked.
- Breast cysts: These develop of fluid accumulates in the breast tissue.
- Ganglion cysts:These can happen from injury, but there isn’t always an obvious cause.
- Pilonidal cysts: Friction or hormones are possible causes of these types of cysts.
- Ovarian cysts: These can form when an egg doesn’t release correctly, and fluid builds up, or when a follicle reseals after releasing an egg and traps fluid inside.
- Baker cysts: These can be caused by injury or certain conditions like arthritis.
- Pilar cysts: These are caused by protein buildup in the hair follicle.
- Mucous cysts: These cysts can be related to piercings, biting your lips, or difficulty with mouth hygiene.
- Branchial cleft cysts: These form during embryonic development when tissues in the neck and collarbone develop abnormally.
- Perineural cysts: These are typically caused by exertion or trauma.
Learn more: What’s causing this cyst?
Can a cyst turn into a tumor?
It’s rare for a cyst to turn into a tumor, as each develops differently. However, this could happen in cases where malignant cells infect a cyst. These are called cystic neoplasms
Some examples include certain
Sometimes doctors recognize cysts during a physical exam, but they often rely on diagnostic imaging. Diagnostic images help your doctor figure out what’s inside the lump. These types of imaging include ultrasounds, CT scans, MRI scans, and mammograms.
Cysts that look smooth, both to the naked eye and in diagnostic images, are almost always benign. If the lump has solid components due to tissue rather than liquid or air, it could be either benign or malignant.
However, the only way to confirm whether a cyst or tumor is cancerous is to have it biopsied by your doctor. This involves surgically removing some or all of the lump. They’ll look at the tissue from the cyst or tumor under a microscope to check for cancer cells.
If the lump is filled with fluid, your doctor might use something called fine needle aspiration. They’ll insert a long, thin needle into the lump to pull out a sample of the fluid.
Depending on the location of the lump, most biopsies and aspirations are done in an outpatient setting.
Treatment for cysts and tumors depends entirely on what’s causing them, whether they’re cancerous, and where they’re located. However, most cysts don’t require treatment.
If it’s painful or you don’t like the way it looks, your doctor can remove it or drain the fluid that’s within it. If you decide to drain it, there’s a chance the cyst will regrow and require complete removal.
Benign tumors also usually don’t need treatment. If the tumor is impacting a nearby area or causing other problems, you may need surgery to remove it.
Cancerous tumors almost always require treatment with surgical removal, radiation therapy, or chemotherapy. In some cases, you may need a combination of these treatments.
When should I see a doctor?
While most cysts and tumors can wait until your next appointment with your doctor, let them know immediately if you notice that the lump has the following characteristics, as these could be signs of cancer, pre-cancer, or infection.
- bleeds easily or oozes
- changes color
- grows quickly
- itches
- ruptures
- looks red or swollen
That said, any change in a lump or appearance of a new lump that doesn’t fit these signs should also be evaluated by a doctor.
Do tumors hurt when pressed?
Tumors can hurt when pressed, and this is more likely with ones that are benign.
Are cysts hard or soft?
Cysts can be either hard or soft, depending on the type. Usually, a softer cyst isn’t cancerous, but there are exceptions.
It’s often hard to tell the difference between a cyst and a tumor — even for doctors. While there are a few things you can look for to help you identify whether a lump is more likely to be a cyst or a tumor, it’s best to make an appointment with your doctor.
They can take a small sample of the lump to determine whether it’s a cyst, tumor, or something else and recommend the best course of treatment.