The fact that Tasmanian devils are prone to a bizarre type of
contagious facial cancer disease was first noted in 1996 in the far north east
of Tasmania, and since then, the disease has spread south and west and now
affects devils in over 85% of their distribution territory.
The disease, termed devil facial tumor disease (DFTD), is
spread by biting, causing the appearance of tumors on the face, jaws and in the oral cavity. The
tumors often become very large and in ~60% of the cases, metastasize to
internal organs, including regional lymph nodes, lungs, spleen, heart and
kidneys.
The tumors kill the host within 6 months of the emergence of
first lesions, due to starvation, secondary infection and metastases
formation.In
contrast to other transmissible cancer diseases, such as the human Burkitt’s
lymphoma and adult T-cell leukemia, which are spread by viruses (Epstein-Barr
virus (EBV) and adult T-cell leukemia/ lymphoma (HTLV-I), respectively), the
DFTD which is spread by biting, appears to be transduced by the cancer cells
themselves being passed from one animal to another.
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