Intensive (2+5) Or Semi-Intensive (FLUGA) Chemotherapy For Patients With Acute Myeloid Leukemia Who Are 70 Years Of Age Or Older

Intensive chemotherapy in patients with acute myeloid leukemia (AML) who are 70 years of age or older leads to an overall survival (OS) lower than 30% at one year. This is due to low tolerability of intensive chemotherapy schedules and biological adverse features of this group of patients.

To evaluate the therapeutic results in AML patients who are 70 years of age or older treated with intensive (2+5) or semi-intensive (FLUGA) chemotherapy.

Multicenter retrospective study based on data of the epidemiologic AML PETHEMA group Registry to evaluate the OS in patients who are 70 year of age or older that have followed the treatment recommendations of the group (LMA2007/2+5 protocol: idarrubicin 12 mg/m² for 2 days plus IV cytarabine 200 mg/m² for 5 days, and two cycles with IV cytarabine 100 mg/m² for 5 days; LMA2011/FLUGA protocol: 3 induction courses with oral fludarabine 40 mg/m² for 4 days plus subcutaneous cytarabine 75 mg/m² for 4 days following maintenance treatment with an outpatient schedule of lower doses of fludarabine plus cytarabine. Patients diagnosed with acute promyelocytic leukemia and/or an ECOG of 4 were excluded.

Of the 155 patients included from 30 hospitals, 78 were treated according to LMA2007/2+5 scheme and 77 to LMA2011/FLUGA recommendations. Median of age in the FLUGA vs 2+5 was 77 years [70-89] vs 74 years [70-81], p<0.001; leukocytes were 27x10⁹/L [0,6-350] vs 40 x10⁹/L [0,4-316], p=0.13; also without significant differences in hemoglobin, platelets, fibrinogen, creatinine, albumin, uric acid and ECOG. Secondary AML affected 28% of patients in the FLUGA schedule and 26% of the 2+5; low/intermediate/high risk cytogenetics was 3%, 66% and 31% in the FLUGA schedule and 7%, 77% and 16% in the 2+5 (p=0.11). Response to induction courses following FLUGA vs 2+5 were: complete remission (CR) 51% vs 37% (p=0.13), CR plus partial remission (PR) 69% vs 47% (p=0.01), mortality 10% vs 24% (p=0.03). Hospitalization rate was 67% in the FLUGA group vs 100% in the 2+5. OS at 6 months and at 1 year were 57% and 40% with FLUGA and 48% and 24% with 2+5 (p=0.03), respectively. In addition to the therapeutic regimen, other factors associated with the OS at one year were CR vs not CR (59% vs 10%, p <0.001) and cytogenetic risk low / intermediate vs high (43% vs 0%, p <0.001).

In patients who are 70 years of age or older, therapeutic recommendations consisting in semi-intensive chemotherapy (FLUGA) led to an improved OS at 1 year compared with intensive chemotherapy (2+5). In this group of patients achieving CR should be a therapeutic goal because it significantly improves the prognosis.

No relevant conflicts of interest to declare.