SummaryWe assessed the safety and efficacy of melphalan, arsenic trioxide (ATO) and ascorbic acid (AA) (MAC) combination therapy for patients with multiple myeloma (MM) who failed more than two different prior regimens. Patients received melphalan (0AE1 mg/kg p.o.), ATO (0AE25 mg/kg i.v.) and AA (1 g i.v) on days 1-4 of week 1, ATO and AA twice weekly during weeks 2-5 and no treatment during week 6 of cycle 1; during cycles 2-6, the schedule remained the same except ATO and AA were given twice weekly in week 1. Objective responses occurred in 31 of 65 (48%) patients, including two complete, 15 partial and 14 minor responses. Median progression-free survival and overall survival were 7 and 19 months respectively. Twenty-two patients had elevated serum creatinine levels (SCr) at baseline, and 18 of 22 (82%) showed decreased SCr levels during treatment. Specific grade 3/4 haematological (3%) or cardiac adverse events occurred infrequently. Frequent grade 3/4 non-haematological adverse events included fever/chills (15%), pain (8%) and fatigue (6%). This steroid-free regimen was effective and well tolerated in this heavily pretreated group. These results indicate that the MAC regimen is a new therapeutic option for patients with relapsed or refractory MM.

A reaction for an esterase, with a nonhalogenated, short-chain naphthyl ester (alpha-naphthyl butyrate or alpha-naphthyl acetate) as the substrate, has been used to identify mononuclear phagocytes by light microscopy. By analyzing techniques used in the collection, separation, fixation, processing, and embedding of human blood leukocytes for electron microscopy, we adapted the light microscopic method for use in determining the fine structural localization of this reaction. In monocytes, the reaction product covered the external surface of the plasma membrane. This distribution indicated that monocytic esterase is an ectoenzyme. The addition of NaF completely inhibited the monocytic reaction. In lymphocytes, the reaction product was localized in membrane-bounded intracellular organelles, similar to those previously shown to contain phospholipid and called Gall bodies. These organelles correspond with the punctate densities or focal reaction product observed by light microscopy. Other investigators believe that this distribution of enzyme in lymphocytes marks a subset of T cells, the Tmicro. The lymphocytic reaction was not inhibited by NaF.

Six women presented with the clinical picture of essential thrombocythemia (ET) without the anemia, marked splenomegaly, and extreme leukocytosis characteristic of chronic myelogenous leukemia (CML). All had the Philadelphia chromosome on karyotype analysis of the bone marrow. Peripheral basophilia was present in four cases, providing a clinical clue that the Philadelphia chromosome might be present. Marrow biopsy showed granulocytic hyperplasia and either small megakaryocytes or sheets of megakaryocytes with marked atypia, findings that are more typical of CML than ET. The clinical importance of finding the Philadelphia chromosome in patients who seem to have ET is in assessing prognosis. ET generally follows a chronic, indolent course. However, five of these six patients who had the Philadelphia chromosome underwent clinical transition to the accelerated phase of CML or blastic leukemia in 4-7 years.

No abstract

No abstract