Use of vincristine in refractory thrombotic thrombocytopenic purpura.

We describe 3 patients with thrombotic thrombocytopenic purpura (TTP) treated with vincristine. In 2 of them, multimodality treatment with plasmapheresis, acetylsalicylic acid, dipyridamole, corticosteroids, and plasma infusions did not achieve lasting remission, subsequent to which the administration of vincristine was followed by prompt and durable remission. In the third patient, 1 mg of intravenous vincristine as initial therapy in conjunction with multimodality treatment resulted in the prompt resolution of the disease. Our experience suggests that vincristine is effective in the treatment of TTP and can be used as initial treatment in combination with other modalities.

Association of T cell acute lymphoblastic leukemia and histiocytic medullary reticulosis.

Seventeen reported cases of acute lymphoblastic leukemia that terminated in a clinical picture of histiocytic medullary reticulosis were reviewed. Using the presence of T cell markers, mediastinal mass, or very high initial white blood cell count as suggestive of T cell acute lymphoblastic leukemia, nine of 13 evaluable cases fulfilled such criteria. This review raises the possibility that the histiocytic medullary reticulosis appearing in the course of T cell acute lymphoblastic leukemia is the result of lymphokine production by the leukemic cells.

Simultaneous occurrence of multiple myeloma and acute myeloblastic leukemia: fact or myth?

A careful search of the literature disclosed 22 cases of the simultaneous occurrence of multiple myeloma and acute leukemia. An additional eight cases of macroglobulinemia and acute leukemia have also been described. Critical review of these reports, however, suggests that the concomitant occurrence of myeloma or Waldenström's macroglobulinemia and acute myeloblastic leukemia is quite uncommon and probably represents a coincidental or chance association.