[Orbital immunoblastosarcoma (author's transl)].

The new classifications adopted for lymphoid tumors now include a particular type of proliferative process: immunoblastosarcoma. This tumor is not a rare occurrence in the orbit, as shown by the two cases reported, and possesses sufficiently specific clinical and histologicas characteristics to justify its appearance in a separate class. The cytological and histological characteristics of the immunoblasts from which it develops are described. Tumors of this type were previously mostly included in the group of reticulosarcomas, now become obsolete because of poorly defined characteristics of the reticular cell. The prognosis is poor in spite of the chemotherapeutic and radiotherapeutic treatments proposed.