American Burkitt's lymphoma-hand-mirror variant. A detailed investigation of cytologic, ultrastructural, and immunologic features.

Previous studies of patients with lymphoid malignancies have suggested a relationship between survival and the presence of more than 40% hard-mirror cells in the bone marrow. This report represents the first detailed study of a patient with American Burkitt's lymphoma with numerous hand-mirror cells in the bone marrow during the course of the disease. The Burkitt cells were atypical because of their hand-mirror configuration in the bone marrow, the presence of cytoplasmic glycogen, the finding of an IgG surface marker, and a strongly positive acid phosphatase staining reaction. The presence of increased numbers of hand-mirror forms in the bone marrow during the course of the patient's illness may have clinical significance, because they were replaced by non-hand-mirror Burkitt cells in the terminal phase. More reports and investigations of patients with large numbers of hand-mirror forms in the bone marrow are needed to elucidate the full significance of this unusual cellular phenomenon.