Additional cytogenetic changes do not influence the outcome of patients with newly diagnosed acute promyelocytic leukemia treated with an ATRA plus anthracycline-based protocol. A report from the Spanish group PETHEMA

Background and Objectives. To analyze, in patients with de novo acute promy elocytic leukemia (APL) treated with an ATRA plus anthracycline-based proto col, whether the presence of cytogenetic aberrations additional to the t(15 ;17) influences: i) clinical and biological presenting features; li) diseas e outcome. Design and Methods. One hundred and thirteen patients with newly diagnosed APL enrolled in the APL-96 protocol of the Spanish PETHEMA group were studi ed by conventional karyotyping, fluorescent in situ hybridization and rever se transcription-polymerase chain reaction for the PML-RAR alpha fusion. Tr eatment was homogeneous in all cases and consisted of anthracyclines and AT RA. Results. Additional chromosome aberrations were observed in 30% of cases. T he most frequent secondary changes were +8 (14 cases), and abnormalities of chromosomes 9 or 3 (4 patients each), and of chromosomes 1 and 8 (3 cases each). No clinical, biological, morphologic, immunophenotypic or molecular differences were observed between the group of APLs with t(15;17) alone and the group of patients with additional changes. Patients with additional ch anges had a higher rate of complete remission (CR) and 4-year disease-free survival (DFS) (97%, and 97%, respectively) than patients with t(15;17) alo ne (CR, 70% and DFS, 84%) but these differences were not statistically sign ificant. Interpretation and Conclusions, Patients with APL and additional cytogeneti c abnormalities do not show different clinical, biological, morphologic or molecular features as compared to patients with t(15;17) alone. The prognos is of patients with APL and t(15;17) alone and those with additional change s is similar in both groups. This study indicates that there is no rational e for administering more intensive treatment in APL patients with additiona l cytogenetic abnormalities receiving ATRA plus anthracycline-based chemoth erapy. (C) 2001, Ferrata Storti Foundation.