Leukaemic conversion of non-Hodgkin's malignant lymphomata.

In 143 patients with poorly differentiated lymphosarcoma, leukaemic conversion has been observed in 25. The cytological type was prolymphocytic or lymphoblastic or lymphoblastoid (immunoblastic ?). Twenty-five patients were treated with chemo-radiotherapy, followed by active immunotherapy as if they had primary acute lymphoid leukaemia. A complete remission was obtained in 11. Four are still in first complete remission after 4 1/2 years. Among 136 patients suffering from so-called "poorly differentiated reticulosarcoma", 17 became leukaemic. The cells are cytologically very dystrophic and unidentifiable. A remission was obtained in 7 patients but it was of short duration (median 1 1/2 months, longest 7 months).