Kategorie: Maligní lymfomy a leukémie
Téma: Acute myeloid leukemia - Clinical
Číslo abstraktu: P623
Autoři: MUDr. Mgr. Cyril Šálek, Ph.D.; MUDr. František Folber, Ph.D.; MUDr. Eva Froňková, Ph.D.; RNDr. Bohumír Procházka; prof. MUDr. Petr Cetkovský, Ph.D.; prof. MUDr. Jiří Mayer, CSc.; prof. MUDr. Michael Doubek, Ph.D.
Ninety-two patients with adult ALL were treated in two major centres in the Czech Republic in 2007–2012. Median age at diagnosis was 37.8 mos. Patients ≤55 yrs. of age were treated according to GMALL 07/2003 protocol, treatment of older patients was not standardised. MRD levels were monitored in bone marrow at clearly defined timepoints.
o evaluate prognostic impact of MRD load at different timepoints of the therapy on overall suvival (OS).
The search for PCR target was performed in 85 pts. PCR marker was found in 78/85 (92%) pts. In 30/85 (35.5%) pts. a fusion gene was found (BCR/ABL in 24 pts., MLL/AF4 in 6 pts.), Ig/TCR rearrangements were monitored in 48/85 (56.5%) pts.. The search for Ig/TCR was undertaken in the group without fusion gene only; the success rate for Ig/TCR detection was 87% (48/55 pts.). MRD negativity (MRDneg) was defined as whatever value <10-4 when outside of quantitative range.
Patients reaching MRDneg after the first course of chemotherapy (day 26) had 3 yrs. OS 78%, n=30 (vs. 52%, n=37) with median survival not reached (vs. 52 mos.) (P=0.036), median time to relapse was not reached (NR) (vs. 34 mos.) (P=0.012). Patients reaching MRDneg after the second induction therapy (day 46) had 3 yrs. OS 77%, n=44 (vs. 46%, n=24) with median survival not reached (vs. 30 mos.) (P=0.023), median time to relapse was NR (vs. 34 mos.) (P=0.066). Patients who were MRDneg at the beginning of consolidation therapy (after previous 2 induction cycles, week 11) had 3 yrs. OS 80%, n=40 (vs. 48%, n=15) with median survival not reached (vs. 30 mos.) (P=0.007), median time to relapse was NR (vs. 10 mos.) (P<0.001). Of 34 pts. who were indicated to alo-HSCT, 24 pts. were MRDneg prior to HSCT. Three-year-OS in MRDneg group was 82% (vs. 45%), median survival NR (vs. 24 mos.) (P=0.034), median time to relapse was NR (vs. 10 mos.) (P=0.005). All 4 pts. who remained MRDpos after the alo-HSCT relapsed in median of 7 mos (P<0.001); median OS was 22 mos. (P=0.005). The mean time to MRD negativity was significantly longer in BCR/ABL+ ALL (105 days) than in other types of B-ALL (44 days) and T-ALL (56 days) (P=0.002).
Summary and Conclusions:
MRD load after the first induction cycle and at the beginning of consolidation therapy has prognostic significance regarding OS and relapse free survival. MRD load prior to alo-HSCT is of prognostic impact as well. MRDpos status within 3 months after the HSCT defines the group with especially unfavorable prognosis. MRD response in BCR/ABL+ ALL is significantly slower than in other adult ALL subgroups.
Datum přednesení příspěvku: 15. 6. 2013