Search

The aim of this study was to describe the presenting features, the frequency and outcome of myeloid sarcoma (MS) diagnosed in our Institution from January 1995 to December 2000. Twelve MS were seen and the frequency account for only 2% of all acute myeloid leukemia (AML) patients observed in our department in the same period. Median age was 45 years (range: 4-84). All had been initially misdiagnosed as malignant lymphoma (ML) and a median of 2.9 months (range: 1-6) elapsed between the misdiagnosis and the correct of MS, effectuated in our department. At that time, a bone marrow examination revealed a myelodysplastic condition in seven patients, an infiltration by blast cells >30% in two patients, and normal features in the other three. In the non-leukemic patients a median of 5 months (range: 2-44 months) elapsed between the diagnosis of MS and acute leukemia. In all, 10 patients received intensive treatment. A total of seven patients (70%) achieved MS complete remission (CR). Patients who presented isolated skin localization and received only radiotherapy, obtained a MS-CR, but subsequently developed AML. Only in patients who were treated within 4 months from the initial ML diagnosis we achieved complete remission of both MS and leukemia, whereas in patients who were treated after this time, we obtained a complete disappearance of MS without response at the bone-marrow level, irrespectively of the specific therapy regimen. Median survival time from MS diagnosis was 7 months (range: 1-49 months), and only one patient is still alive, 49 months after bone marrow transplantation. Our data stress the importance of an accurate and prompt identification of this rare form of AML, and suggest that, even in patients with isolated MS, the early administration of AML-like intensive chemotherapy followed by bone marrow transplantation might reduce the risk of subsequently developing systemic disease.

Myelodysplastic syndromes (MDS) evolve in overt acute nonlymphocytic leukemia (ANLL) in about 40% of patients: the treatment of ANLL-MDS is not yet well clarified. To identify the role for aggressive and conservative approaches in ANLL-MDS, we evaluated retrospectively 78 patients in a 7-year period. Thirty-one patients (16 males and 15 females, median age 57.5 years, median MDS duration 5.5 months) were eligible for aggressive chemotherapy; 17 patients (54.8%) achieved complete remission (CR), 10 (32.3%) were resistant and 4 (12.9%) died during induction from infective complications. All patients that achieved CR relapsed, with a median CR duration of 6 months (range 2-28 months); median survival of the whole group was 8.5 months, while median survival of responders was 9 months. No prognostic factor revealed a statistical significance in the outcome, due to the small number of patients in each subgroup. Forty-seven patients (27 male and 20 female, median age 71.8 years, median MDS duration 10.1 months) were not eligible for aggressive chemotherapy; 16 patients (34.2%) received supportive care only, 31 patients (65.8%) needed conservative chemotherapy for disease progression. Median survival of the conservatively treated group was 5.5 months, without statistical difference from the aggressively treated group; 10/47 conservatively treated patients (21%) survived for longer than 12 months. In conclusion, aggressive chemotherapy may play a role only in a selected population of ANLL-MDS patients, while further studies could be helpful to identify the optimal conservative approach.

A monoclonal antibody (S17-12), previously described to recognize subsets of myelomonocytic cells, is demonstrated to bind CD9 antigen, a surface marker of B-cell precursors, platelets and several non-hematopoietic tissues. The proportion of S17-12, CD9-positive leukemic cells was determined in 102 patients with acute non-lymphocytic leukemia. It was found to be above 75% in 14/22 M3 cases (including 3/3 of microgranular variant) and only in 1/80 cases of different FAB subtype. Complete reactivity (greater than 95%) of leukemic clonogenic cells with CD9 MoAB was restricted to 4/18 M3 cases. Therefore, a high proportion of CD9-positive cells seems to be peculiar to M3 cases. This may help in the diagnosis of cases that lack typical morphological features.

Thirty patients with advanced acute leukemia and lymphoma were treated with the sequential combination of high dose ARA-C (HiDAC 3 gm/m2 infused i.v. over 3 h at 0, 12, 24, 36 h) and asparaginase (ASP 6.000 IU/m2 i.m. at hour 42). The sequence was given on day 1 and 8 irrespective of the degree of myelosuppression. Of 22 patients with leukemia there was only one who was absolutely refractory to therapy. Complete remission was induced in 3 patients with ANLL (30%) and in 3 with ALL (30%). Three patients became hypoplastic but recovered with blasts and 12 died from infection, complicated by intracranial hemorrhage in 3, during hypoplasia. Of 8 patients with lymphoma, 2 were clearly refractory to therapy, one died from sepsis and the remaining 5 all entered remission (2 CR + 3 PR, 62%). Activity of HiDAC/ASP against CNS disease is suggested by the clinical response seen in patients with overt meningeal or intracerebral involvement. Toxicity associated with HiDAC/ASP was mainly hematologic. All but one patient experienced hypoplasia and severe pancytopenia; documented infections and major hemorrhages occurred in 80 and 20% of patients respectively. We conclude that HiDAC/ASP is a regimen with definite activity against acute leukemia and lymphoma including CNS disease. Alternate treatment schedules should be explored in order to reduce marrow toxicity.