A Lump on the Back: 7 Possible Causes

A lump on the back becomes a cause for alarm for many people. However, in most cases, there's nothing to fear.
A Lump on the Back: 7 Possible Causes

Written by Edith Sánchez

Last update: 27 July, 2022

A lump on the back isn’t usually a sign of a serious health problem. That said, there are also cases in which these lumps are manifestations of very severe illnesses. That’s why you should always pay attention to them.

These lumps sometimes have the same color as the skin, sometimes they have a reddish color, and even other tones.

Although most of the time there should be no cause for concern, it’s best to consult a doctor if a ball appears on the back. As we will see below, the causes are very diverse and it is best to take a preventive approach.

Common causes of a lump on the back

It’s very easy for a lump on the back to go unnoticed. Sometimes it’s only detected if it’s accompanied by pain or is very noticeable.

Therefore, it’s advisable to check your back from time to time, either by looking in the mirror or by feeling the area. The main causes of this manifestation are the following.

1. Lipoma

This is one of the most common causes of the appearance of a lump on the back. Lipomas are tumors composed of fat cells that appear under the skin.

Their main characteristic is that they’re soft and mobile. They usually grow slowly and don’t cause discomfort.

It’s very rare for lipomas to turn into cancer. They don’t change the color of the skin and are almost always small. They rarely exceed 5 centimeters (2 inches). Sometimes they’re painful if they’re near nerves or blood vessels.

They usually don’t require treatment unless they cause a lot of discomfort. If they grow too large, they should be removed by surgery under local anesthesia.

A lump on the back.
Malignant lipomas are usually large and don’t go unnoticed, due to their bulky growth.

2. Angioma, or cavernous hemangioma

Angioma is a superficial reddish lesion. It’s a grouping of small blood vessels. It can appear in any area of the body and sometimes takes the form of a lump on the back. Its size is very variable.

When the grouping isn’t small blood vessels, but larger ones, it’s called a cavernous hemangioma. This is usually blue and has no defined margins. It hardly ever measures more than 6 centimeters (2.4 inches). It clears up on its own, although a white trace or hanging tissue may remain.

3. Sebaceous cyst

Another common cause of a ball on the back is a sebaceous cyst. This is a sebaceous mass, soft in texture, that can move.

It hardly ever hurts, but, if it does, it also often takes on a reddish tinge and increases in temperature. If it grows larger than 1 centimeter (0.4 inches) or hurts a lot, it will require medical attention.

4. Boils

A boil is an infection at the root of the hair that gives rise to a reddish bump with pus, very similar to a pimple. The area where it’s located usually feels warmer and it can be quite painful.

The boil looks like a lump on the back or other parts of the body. Even though it’s usually painful, it usually disappears after a few days. If it doesn’t, or if it grows too much, it’s best to visit a dermatologist.

5. Dermatofibroma

Dermatofibroma is a skin tumor caused by the accumulation of collagen. It’s usually red or brown and measures no more than 1.25 centimeters (half an inch) in diameter.

It’s also known as benign fibrous histiocytoma. The consistency of these tumors is hard to the touch and they’re only mobile when pressure is exerted. They rarely cause itching or pain.

Most commonly, dermatofibromas don’t require treatment as they rarely cause symptoms. If they cause pain and itching, or begin to grow, then it’s best to consult a physician.

They can be removed by surgery.

6. Epidermoid cysts

Another possible cause of a ball on the back is an epidermoid cyst. It’s very similar to a sebaceous cyst, but it isn’t the same.

It’s a non-cancerous mass that grows slowly under the skin. It’s usually small and round, with a dark pimple in the center.

It’s filled with a foul-smelling yellow substance, which sometimes drains. If this type of cyst becomes inflamed or infected, it causes redness and tenderness in the area.

7. Skin cancer

Only very rarely is a lump on the back a manifestation of cancer. When it is, it’s usually basal cell cancer. This manifests as small spots that grow gradually.

The lesions look like small elevations, similar to a wound that doesn’t heal. They are pink or brown and it is possible to see blood vessels in them. Bleeding is common.

This type of cancer can be treated with laser surgery or by applying cold to the area to kill the malignant cells. Chemotherapy or radiation therapy may also be required.

A lump on the back.
Regular check-ups of questionable lesions on the back are essential to prevent serious cases of skin cancer in this area.

When to consult a doctor?

Whenever a lump appears on the back it’s important to follow it up.

If the lump is hard and doesn’t move, even though it doesn’t cause pain, it’s best to consult a doctor. This is also the case if these growths disappear and then come back repeatedly.

It’s very important to be attentive to the growth. If it’s suspicious, it would be best to take one photograph per week, always at the same distance. In this way, you can check whether it’s growing or not.

Finally, you should also see a doctor if the lump on the back causes pain or other discomfort, feels red and hot, or drains pus.

A lump on the back is very rarely cancerous, however, it could cause complications if not treated.

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