The Cause of Fatty Lumps on the Back

Fatty lumps on the back are common and cause concern among people who suffer from them. It’s necessary to differentiate them from other pathologies to apply an adequate treatment.
The Cause of Fatty Lumps on the Back
Leonardo Biolatto

Written and verified by the doctor Leonardo Biolatto.

Last update: 27 May, 2022

The discovery of fatty lumps on the back usually causes concern in the person who finds them. Sometimes there isn’t a single one, but one that’s accompanied by other smaller lumps, which worries the person even more.

In any case, it’s important to establish a differential diagnosis of the lesion. In other words, although it may look like a fatty lump, it may be another pathology, such as a sebaceous cyst or a boil.

Although it’s true that fat is the most common cause of this symptom, it doesn’t hurt to get it checked by a doctor to discover the real cause of the problem. Sometimes, an examination alone is enough to determine the origin of the lump, without the need for further tests.

Specifically, an accumulation of fat on the skin is called a lipoma. The name refers to its conformation, which consists of adipocytes, which are fat cells.

Lipomas aren’t malignant, and are generally limited to a size that doesn’t affect other body structures. However, giant lipomas and internal lipomas can lead to unexpected complications, to the point of interrupting the functioning of other organs.

Differential diagnosis of fatty lumps

As we stated above, the existence of a fatty lump on the back requires a differential diagnosis. You have to discover whether you’re dealing with a lipoma or another skin lesion with similar symptoms. Below, we detail the three most common ones.

A woman with fatty lumps on the back.
As we stated above, the existence of a fatty lump on the back requires a differential diagnosis. This way, a medical professional can determine the type of lesion.

1. Lipoma

This is a classic fatty lump. It grows slowly and progressively, and becomes evident when the patient discovers it, sometimes by accident. It isn’t painful and reaches a point of balance where it stops growing, with the exceptions we mentioned. If it’s small, doctors often recommend doing nothing. However, if it’s large or aesthetically bothersome, you can remove it with local surgery.

2. Boil

A boil is an infection of a hair follicle. It can appear on your back, especially in the lower area, where there’s more hair. Sometimes, it hurts, while other times it doesn’t. The pain is usually associated with infection.

If there’s such a complication, pus appears, which exerts pressure in an effort to come out. This is why it differs from a lipoma, which doesn’t have secretions. Treatment of a boil consists of antibiotics if there’s an infection, drainage if there’s pus, and wound washes with antiseptics.

3. Sebaceous cyst

This lesion is very similar to lipomas, as it also contains fat. However, the histological difference is that it has a cyst coating and fluid inside. Although sebaceous cysts hardly ever hurt, they can become infected, like a boil.

They move and even sink a little with pressure. Like a lipoma, treatment is based on its size and the discomfort it causes. If the patient decides to remove it, they’ll need local surgery to do so.

Symptoms and risk factors

Fatty lumps or lipomas are common on the back. Nevertheless, they can also appear on the upper limbs and neck. It isn’t common for them to appear on the lower limbs.

When you touch a lipoma, it moves around a bit and feels soft. It can sink when pressured but it isn’t liquid like a cyst. Thus, it offers some resistance to palpation. It’s usually easy for doctors to identify them, due to these characteristics.

Most fatty lumps don’t exceed 1-2 inches. If it’s larger, it’s probably a giant lipoma, which is an entity in itself. It requires a different approach because it penetrates deeper structures and it isn’t easy to remove, as in other cases.

Experts don’t know the exact origin of lipomas. They assume that there’s some kind of genetic link, since fatty lumps appear repeatedly in family groups with this tendency. But, as of yet, there are no conclusive studies.

Regarding age, the most affected group is adults between the ages of 30 and 60. Also, there’s no clear information on why they mostly affect adults.

A woman with a lipoma.
Lipomas can be large in some patients, even affecting the functionality of other organs.

Keep reading: Everything You Need to Know about a Lump in the Neck

When to see your doctor if you have a fatty lump on your back

If you notice a fatty lump on your back, you should go to see your doctor for a differential diagnosis. The medical professional will be able to quickly distinguish whether it’s a lipoma or another condition. Likewise, they’ll indicate complementary methods or not, based on the seriousness.

Some added symptoms warn of the need to go see your doctor quickly, such as:

  • If the fatty lump gets bigger
  • Presence of pus that drains
  • Hardening of the supposed lipoma, with loss of mobility and softness
  • Swollen glands near the area

Pay attention to fatty lumps

Although lipomas are benign, they require attention. It’s best to see your doctor for a differential diagnosis than to remain in doubt. Even more so, if your symptoms lead you to suspect an infection, compression of neighboring structures, or enlargement of size.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Laín, Alberto Lozano, and José Alberto Codina Silva. “Enucleación quirúrgica de quiste sebáceo en la región mandibular.” Revista Mexicana de Estomatología 4.1 (2017): 37.
  • Monsel, G., V. Pourcher, and E. Caumes. “Infección cutánea bacteriana.” EMC-Tratado de Medicina 22.2 (2018): 1-7.
  • Michal, Michael, et al. “Dysplastic Lipoma.” The American journal of surgical pathology 42.11 (2018): 1530-1540.
  • Lipoma, Endobronchial. “Endobronchial lipoma.” Singapore Med J 58.8 (2017): 510-511.
  • Shanks, John A., W. Paranchych, and J. Tuba. “Familial multiple lipomatosis.” Canadian Medical Association Journal 77.9 (1957): 881.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.