Fat necrosis

Fat necrosis
Other namesalso known as Balser's necrosis
Micrograph of breast tissue showing fat necrosis. H&E stain
SpecialtyPathology

Fat necrosis is necrosis affecting fat tissue (adipose tissue).[1] The term is well-established in medical terminology despite not denoting a specific pattern of necrosis.[2] Fat necrosis may result from various injuries to adipose tissue, including: physical trauma, enzymatic digestion of adipocytes by lipases,[3] radiation therapy,[4] hypoxia, or inflammation of subcutaneous fat (panniculitis).

The gross appearance of fat necrosis is as an irregular, chalky white area within otherwise normal adipose tissue.[1]

Pathophysiology

Trauma

Traumatic injury of adipose tissue liberates stored fat[1][3] as well as lipases[1] from adipocytes. The extracellular fat then elicits a swift inflammatory response, attracting macrophages and polymorphonuclear leukocytes which proceed to phagocytose the freed fat. The process eventually leads to fibrosis. The necrotic tissue may eventually form a palpable mass (especially if situated at a superficial site like the breast).[3]

Traumatic fat necrosis commonly affects the breast and may resemble a tumour (especially in case of calcification of the necrotic mass).[1]

Enzymatic digestion

Pancreatic conditions like acute pancreatitis,[3] pancreatic carcinoma, and pancreatic trauma[5] result in liberation of pancreatic lipase which proceeds to digest fat to form free fatty acids which subsequently combine with calcium to form soapy precipitates.[3][2]

Although the peripancreatic region is the most commonly affected (due to direct contact with enzymes), associated fat necrosis may occur throughout the body in subcutaneous tissue, hand and foot joints, and bone marrow. These extrapancreatic complications are known as pancreatic panniculitis.[5]

Clinical significance

Breast fat necrosis

Causes

Examples of causes include but are not limited to:[citation needed]

Epidemiology

Fat necrosis in the breast occurs around 0.6%, this represents 2.75% of lesions that end up being benign. However, 0.8% of fat necrosis occurs from tumors of the breast, 1–9% occurs in breast reduction surgery. Individuals that are high risk include women around the age of 50yrs along with pendulous breasts.[8]

See also

References

  1. ^ a b c d e Strayer, David S.; Rubin, Emanuel; Saffitz, Jeffrey E.; Schiller, Alan L., eds. (2015). Rubin's Pathology: Clinicopathologic Foundations of Medicine (7th ed.). Philadelphia: Wolters Kluwer Health. pp. 34–35. ISBN 978-1-4511-8390-0.
  2. ^ a b Kumar, Vinay; Abbas, Abul K.; Aster, Jon C., eds. (2015). Robbins and Cotran pathologic basis of disease (Ninth ed.). Philadelphia, PA: Elsevier/Saunders. pp. 43–44. ISBN 978-1-4557-2613-4.
  3. ^ a b c d e Cross, Simon S. (2013). Underwood's Pathology (6th ed.). Churchill Livingstone. p. 85. ISBN 978-0-7020-4672-8.
  4. ^ "fat necrosis". www.cancer.gov. 2011-02-02. Retrieved 2024-06-16.
  5. ^ a b Lee, P. C.; Howard, J. M. (May 1979). "Fat necrosis". Surgery, Gynecology & Obstetrics. 148 (5): 785–789. ISSN 0039-6087. PMID 432796.
  6. ^ Kerridge, William D.; Kryvenko, Oleksandr N.; Thompson, Afua; Shah, Biren A. (2015-03-16). "Fat Necrosis of the Breast: A Pictorial Review of the Mammographic, Ultrasound, CT, and MRI Findings with Histopathologic Correlation". Radiology Research and Practice. 2015: 613139. doi:10.1155/2015/613139. PMC 4378709. PMID 25861475.
  7. ^ Genova, Rafaella; Garza, Robert F. (2020), "Breast Fat Necrosis", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 31194348, retrieved 2020-11-12
  8. ^ Rice, Hannah; Warland, Jane (October 2013). "Bearing Witness: Midwives experiences of witnessing traumatic birth". Women and Birth. 26: S39. doi:10.1016/j.wombi.2013.08.215. ISSN 1871-5192.