As the cancers develop in affected devils, they may become emaciated, particularly if the tumours interfere with teeth and feeding. Many females lose their young. Affected animals appear to die within six months of the lesions first appearing.

The Tasmanian devil, a large carnivorous Australian marsupial, is under threat from a widespread fatal disease in which a malignant oral-facial tumour obstructs the animal's ability to feed. Here we show that the chromosomes in these tumours have undergone a complex rearrangement that is identical for every animal studied. In light of this remarkable finding and of the known fighting behaviour of the devils, we propose that the disease is transmitted by allograft, whereby an infectious cell line is passed directly between the animals through bites they inflict on one another.

The impact and distribution of Tasmanian devil facial tumour disease (DFTD) is being monitored in wild populations around the State. DFTD has now been recorded across the eastern half of Tasmania and as far west as Cradle Valley. In recent weeks, the disease has been confirmed at Fentonbury and Adamsfield in the south, and immediately north of Eaglehawk Neck on the Forestier Peninsula. So far, the disease has only been recorded in wild Tasmanian devils.

The lips are not defined as belonging to the oral cavity in the TNM-system, and are therefore mentioned separately here. Among the benign conditions hemangiomas are not unusual. They are found on the mucosal side of the lip, have a bluish hue and can be compressed to make the color disappear. They bleed when bitten, and are usually easy, if not too large, to remove surgically. Large hemangiomas may occasionally require radiotherapy or laser treatment.