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Fat necrosis is a lump that forms as a result of damage to an area of the fatty breast tissue.
Fat necrosis is benign (non-cancerous) and does not increase the risk of developing breast cancer. It can affect women of any age.
Many women don’t remember any specific injury causing the fat necrosis.
Fat necrosis feels like a firm, round lump and doesn’t usually cause any pain. The skin around the lump may look red, bruised or dimpled.
Fat necrosis usually becomes noticeable as a lump in the breast. Your GP is likely to refer you to a specialist at a breast clinic.
A definite diagnosis can be made through a triple assessment: a breast examination; a mammogram or ultrasound scan; and a fine needle aspiration cytology (FNAC) or core biopsy.
If you are under 35 you’re more likely to have an ultrasound scan than a mammogram as younger women’s breast tissue is often too dense to give a clear mammogram image.
If you’ve been told you have fat necrosis you won’t usually need any treatment or follow up. Fat necrosis often goes away by itself.
If the lump doesn’t disappear, or gets bigger, you may need to have a small operation to remove it. You may also need an operation if the biopsy hasn’t given enough information to confirm fat necrosis.
Your operation can be done using either a local or a general anaesthetic, and you may be in hospital for the day or overnight.
You’ll have a small wound with a stitch or stitches in it, and your doctors will tell you how to care for it afterwards.
Having fat necrosis does not increase your risk of developing breast cancer. However, it’s still important to be breast aware and go back to your GP if you notice any other changes in your breasts.