Malignant transformation

Malignant transformation
In genetics, "transformation" is also used to describe the incorporation of foreign DNA by bacteria.

Malignant transformation is the process by which cells acquire the properties of cancer. This may occur as a primary process in normal tissue, or secondarily as malignant degeneration of a previously existing benign tumor.

There are many causes of primary malignant transformation, or tumorigenesis. The underlying commonality is genetic mutation either by inheritance or more commonly by acquiring mutations in one's DNA over time. Although malignant transformation may occur because of changes within the cell, it can be induced by inorganic toxic substances such as cadmium or arsenite and organics such as tobacco-specific nitrosamines. It is also thought that some malignant transformations are due to viruses such as the Epstein-Barr virus, although this is currently restricted to just a few cancer types. A more common cancer associated with viral infection is cervical cancer, which has been linked to the human papilloma virus.

Malignant transformation of cells in a benign tumor may be detected by pathologic examination of tissues. Often the clinical signs and symptoms are suggestive of a malignant tumor. The physician, during the medical history examination, can find that there have been changes in size or patient sensation and, upon direct examination, that there has been a change in the lesion itself.

Risk assessments can be done and are known for certain types of benign tumor which are known to undergo malignant transformation. One of the better known examples of this phenomenon is the progression of a nevus to melanoma.

References

  • M.Monti; L'ulcera cutanea: approccio multidisciplinare alla diagnosi ed al trattamento; Milano 2000. ISBN:8847000726 9788847000728 .
  • Mazzeo Francesco; Trattato di clinica e terapia chirurgica; Padova, 2001- ISBN:8829915661 9788829915668.
  • Fishman J.R.A., Parker M.G.; Malignancy and chronic wounds: Marjolin's Ulcer. J. Bum Care and Rehab., 12, 3: 1991.

See also



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