Necrosis

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Necrosis (left of image) in a seminoma (right of image). H&E stain.

Necrosis is a type of cell death that is characterized by inflammation.

It is always pathologic. The differential diagnosis of necrosis is very broad; it is important to not be focused only on cancer and infections.

Classic types

As per Robbins:[1]

  • Coagulative.
  • Liquefactive.
  • Gangreneous.
  • Caseous.
  • Fatty necrosis.
  • Fibrinoid.

Coagulative

Features:[2]

  • General: most common; proteinlysis > autolysis/heterolysis.
  • Where/when: all tissue except the brain.
  • Microscopic: cell outlines present.

Liquefactive

Features:[2]

  • General: proteinlysis < autolysis/heterolysis.
  • Where/when: infections, brain, abscess.
  • Microscopic: nothing left; pink on H&E.

Other classic types

  • Gangrenous: coagulative necrosis in ischemic limb.
  • Caseous: cheesy material; tuberculosis.
  • Fat: adipose tissue, e.g. pancreatitis.
  • Fibrinoid: immune complex mediated; bright-pink in vessel walls.

Other types

Gross

Coagulative necrosis:

  • Soft.
  • Grey or white.

Liquefactive necrosis:

  • Mushy, grey.
  • Porridge-like consistency.

Image:

Microscopic

Features:[3]

  • Dead cells - (too much pink on H&E) - one of the following:
    1. Anucleate cells ("Ghost cells") - outlines of cells only.
      • Usually subtle.
      • Fluffy appearance.
    2. Karyolysis - nucleus disintegrating.
    3. Karyorrhexis - nucleus fragmenting.
    4. Pyknosis - nuclear strinkage.
      • Weak sign.
  • Inflammation - typically neutrophils (very common).

DDx of necrosis:

  • Fibrin.

Notes:

  • Inflammation is a reactive phenomenon; it requires blood flow.
    • Post-mortem it is not found.

Images

www:

Stains

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LESION, ANTERIOR RECTUS WALL, SURGICAL BIOPSY:
- EXTENSIVE FAT NECROSIS.
- NO EVIDENCE OF MALIGNANCY.

Micro

The sections show fibroadipose tissue with abundant foamy histiocytes and necrotic adipocytes. Scattered chronic inflammatory cells, including plasma cells eosinophils and lymphocytes, are present. Focally hemosiderin-laden macrophages are identified. Multi-nucleated giant cells are seen. No definite epithelium is identified. Some reactive fibroblasts are present. No significant nuclear atypia is identified.

See also

References

  1. Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 21-22. ISBN 0-7216-0187-1.
  2. 2.0 2.1 Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 6. ISBN 978-1416054542.
  3. Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 4. ISBN 978-1416054542.
  4. URL: http://moon.ouhsc.edu/kfung/jty1/Com08/Com801-1-Diss.htm. Accessed on: 3 November 2010.