Acute myeloid leukemia in elderly patients aged over 75 years: experience of a single centre.

The treatment of acute myeloid leukemia (AML) in elderly patients is still controversial and the results of chemotherapy remain unsatisfactory compared with those obtained in younger patients [1,2]. However, a group of elderly patients eligible for intensive chemotherapy can be identified among those with good performance status (PS) and without severe associated diseases [3,4]. Among these patients age is the only variable with statistical significance associated with survival and patients older than 70 years, have a shorter survival rate than those aged between 60 and 70-years-old [2–5,6]; in fact, data confirms that intensive chemotherapy is generally not indicated for patients over 75 years [7]. In this study we have retrospectively analyzed all patients with AML aged 75 years and over admitted in our institution between January, 1990 and December, 1999. In all patients, we analyzed demographical parameters, age, sex, F.A. B. subtype, hematological and chemical parameters at diagnosis of AML. Furthermore, we evaluated the clinical presentation, PS according to W.H. O. classification, chemotherapy administered, toxicity of chemotherapy and the outcome (i.e. complete remission (CR) achievement, CR duration and overall survival). During the study period, 385 patients with acute leukemia were admitted to our institution: 22 were ALL (21%) and 303 AML (79%). Among AML patients, 164 (54%) were elderly patients over 60-years-old and 36 of them were older than 75 years. These 36 patients were 11 males and 25 females with a median age of 80 years (75–91). Twelve patients (33%) presented a preexisting myelodysplasia and 3 patients (8%) presented a previous malignancy (1 colon carcinoma, 1 melanoma, 1 throat carcinoma) only treated with surgery. In Table I, the main patients laboratory parameters and clinical characteristics are summarized. In 28 patients the diagnosis of AML, based on F.A. B. criteria, was the following: 4 M0, 3 M1, 8 M2, 5 M4, 7 M5, 1 M6; 4 patients presented a post MDS leukemia and the F.A. B. classification was not applicable. In 4 patients, due to their bad clinical presentation, bone marrow exam was not performed and diagnosis of AML was made only with peripheral blood analysis. Cytogenetic study was effected in 24 patients. According to cytogenetic characteristics, elsewhere reported [8], the patients were assigned to favorable, intermediate, and adverse-risk categories. Ten patients (28%) with bad PS (W.H.O. 3 or 4) received only supportive care (blood and platelets transfusions, antimicrobial therapy) and died shortly after the diagnosis (median survival 6 days, range 1–10). The remaining 26 patients, eligible for chemotherapy, were divided in two groups: group 1 included patients who received an intensive treatment including anthracyclines þ /2 etposide (11 patients); group 2 patients who received a less intensive care, i.e. low doses of cytosine arabinoside (Ara-C) and/or hydroxyurea (15 patients). The two groups of patients do not differ in age, sex and laboratory parameters, but the patients treated less aggressively presented more frequently W.H. O. score . 2 (80 vs. 27%). No statistical differences were observed in CR rate or CR duration and overall survival. Five patients (45%) achieved CR in group 1 and 3 patients (20%) in group 2. No differences were observed among the number of resistant (27 vs. 20%, respectively). Four out of the 5 patients who achieved CR in the first group received further post-remission therapy with a similar schedule of chemotherapy. Two patients received a maintenance therapy with thioguanine and cytarabine. Two out of 3 patients in group 2 who obtained CR received a post-remission therapy with low doses of cytarabine. Among the 6 patients who received a post-remission