Devil Facial Tumour Disease (referred to as DFTD) is the name given to a fatal condition that is afflicting a significant portion of the native population of Tasmanian devils. The condition first becomes noticed as small lesions or lumps around the mouth that develops into large tumours predominantly around the face and neck, but sometimes in other parts of the body as well.
DFTD was first reported in the mid 1990’s and has now been confirmed in most areas throughout Tasmania except for north-west and west coast devil populations. It is having a major impact in areas with high-density populations, and is predominantly affecting the adult populations. The disease does not usually become apparent in devils until they are at least two years old. The cancers affect the capability of the devil to ingest food thereby weakening the animal and making it more difficult for it to compete with other animals for food. Evidence suggests that animals appear to die within three to five months of the lesions first appearing, from starvation and the breakdown of body functions.
There are three well-known types of malignant skin tumours. In all of them the ultraviolet rays from the sun plays a significant etiological role. The most common one is basal cell carcinoma or basaloma, which does not metastasize and is the more benign of the three types. Sometimes it grows very aggressively with a great tendency for recurrence, and destroys underlying tissue, bone, cartilage etc., with pronounced cosmetic and functional defects as a consequence.
A facial tumour disease is continuing to ravage Tasmania’s wild devils, with almost half of the devil population believed lost to the disease. Fears the disease is spreading have been realised, with 3 new cases discovered in the south of the state.
Malignant melanoma is the type of tumour presently increasing the most in incidence. It spreads both through lymphatic pathways and hematogenously, and in the long term has a bad prognosis, especially if the tumour is not discovered until it has grown deep into the skin. It is usually pigmented by the melanin in the melanocytes. This may not always be the case, as so-called amelanotic , i e not blue or brown colored, melanomas exist.
The disease has now spread across 65 per cent of the state, with 3 new cases discovered in southern Tasmania. The disease is across the eastern part of the state and extends as far west as the Cradle Valley, and also down into the south of the state. To date we haven’t recorded the disease on the west coast or in the far north-west, so it’s in the eastern parts of the state that the disease is having the greatest impact.