Abstract

The Tasmanian devil facial tumour disease (DFTD) and the canine transmissible venereal tumour (CTVT) are the only two known naturally occurring clonally transmissible cancers. These cancers are spread by the physical transfer of living cancer cells between unrelated individuals. DFTD is spread by biting and is threatening its host species, the Tasmanian devil, with extinction. CTVT is a sexually transmitted cancer affecting domestic dogs that first arose more than ten thousand years ago and has spread around the world together with its host. A remarkable feature of transmissible cancers is their ability to escape their hosts’ immune systems despite their status as allogeneic grafts. I will review the current understanding of the mechanisms of DFTD and CTVT immune evasion and will discuss insights revealed by