Canadian doctors are reporting the case of a man with severe autism who developed an extremely rare super-giant basal cell carcinoma (BCC) measuring 25cm, after avoiding medical care for a decade.

The 51-year-old man presented to the dermatology clinic at McMaster University in Hamilton, Ontario, with two large friable ulcers, on his back and left anterior chest wall.

The lesions first appeared 10-12 years ago but the man, who had severe autism and a history of isolation and avoiding medical services, had not sought earlier treatment.

The endophytic ulcerating lesion on his back had sharply demarcated rolled borders with significant ulceration into the muscle and potentially the bone.