Fat necrosis is the destruction of fat cells inside the body. It is usually benign, but it can be a symptom of a more serious underlying problem. People often report to the doctor for treatment because it results in the formation of a hard lump at the site of the destroyed cells and the patient may think that the lump is a tumor or another cause for medical concern. Treatment for fat necrosis varies, depending on the location and the underlying causes.
In fat necrosis, fat cells are broken down by the body, usually in response to trauma. It can happen after surgery, as a result of physical stress, in the wake of radiation therapy, and in association with chronic diseases like pancreatic disease. As the cells break down, a mass of rubbery tissue can form. This lump will be palpable to the patient if it is near the surface.
A common site for fat necrosis is in the breast. Patients usually view lumps in the breast as a cause for concern and may seek medical treatment when they identify the unusual deposit of tissue. Other areas where this condition can arise include the thighs, where a lump will also be palpable, and in the fat that surrounds the kidneys. In this last case, the necrosis will usually be identified by a doctor during other diagnostic testing involving the kidneys such as an imaging study.
In the case of lumps in sites like the breast and thighs, it is not uncommon for the skin above the site of the necrosis to become mottled or lumpy. The patient may feel pain or heat in the area as a result of inflammation, and sometimes discharges develop. Treatment for fat necroses can include warm compresses along with anti-inflammatory medications to reduce the pain and swelling associated with the lump. In the breasts, the lump may be biopsied if a doctor cannot confirm that it is caused by fat necrosis through medical imaging such as mammography.
When the fat around the kidneys is damaged, it is indicative of kidney disease. The patient will need treatment for the kidney disease, including monitoring of kidney function. Another type of fat necrosis can be seen in newborns after traumatic births. The newborn may be worked up for signs of undiagnosed complications from the birth and treatment will be provided to address the lump of scar tissue that forms at the necrosis site.