Monocytic sarcoma of the sclera.

A patient with acute monocytic leukaemia and gross ocular involvement successfully treated with local irradiation is described. Leukaemic infiltration of the sclera developed at a time when the patient appeared to be in haematological remission. Despite the frequency of extramedullary disease in monocytic leukaemia the diagnosis of monocytic sarcoma may be very difficult.