NCIt definition : A spectrum of T-cell lymphoproliferative disorders that arise from the mucosal sites
of the head and neck. They are characterized by the presence of CD30-positive neoplastic
lymphoid cells with pleomorphic nuclei and abundant cytoplasm. Cells that resemble
the hallmark cells of anaplastic large cell lymphoma are often seen. The lesions usually
arise from the oral cavity and, less frequently, the conjunctiva, orbit, and nasopharynx.
In most cases complete remission is achieved, following excision, with or without
radiotherapy, and with or without systemic chemotherapy.;