Characteristics And Prognosis Of Patients Diagnosed As De-novo Acute Myeloid Leukemia With Chromosome 8 Abnormality

Objective To explore the clinical features and prognosis of de novo acute myeloid leukemia(AML) with chromosome 8 abnormality.Methods Collecting 25 patients diagnosed as de novo AML with chromosome 8 abnormality from May 2007 to May 2014 admitted to The People’s Liberation Army Hospital 307. The last follow‐up was October 1st 2015. The mean follow‐up was 29.8 months(1.5‐87);This paper analyzed characteristics of their gender,age, sub‐type of FAB, blood routine,percentage of bone marrow leukemia blast cells,chromosome aberration and gene mutation at first visit and explore the relationship between the characteristics and CR(complete response) rate as well as the prognosis.Results Among 25 AML patients, 1 case of M3 with tetrasomy 8, 24 cases of patients with trisomy 8. 12 cases diagnosed as M5(50%),while M2,M3,M4 and M6 had 3 cases respectively(12.5%); 1case did not receive chemotherapy and eventually survived 5 months under palliative therapy. 24 patients received 1‐2 cycles of standard induction chemotherapy, after CR1 either consolidation chemotherapy or allo‐HSCT with HLA‐matched sibling donor were performed. Among 4 cases of M3, 3 cases had chromosome 8 aberration(2 cases with trisomy 8 and 1 case with tetrasomy 8) as well as t(15,17)(q22,q12), the last case with trisomy 8 sole without t(15,17)(q22,q12). ALL the 4 cases M3 had RARA gene mutation; After received 2 cycles of arsenic acid combined with HA regimen chemotherapy, the case with tetrasomy 8 achieved CR1, but he lost to follow‐up after 13 months. The other 3 cases achieved CR1 after receiving only 1 cycle of arsenic acid combined with HA regimen chemotherapy; 1 case of 3 patients of M3 in CR1 relapsed two times, at the very beginning of second relapsed, the karyotype evolved to complex karyotype and he achieved CR3 at last visit. The other 2 cases kept CR1 until last visit. their mean over survival(OS) was 76.3 months(64‐87), and the 5‐year OS was 100%. Among 20 cases of non‐M3, 12 cases achieved CR1, 4 cases achieved partial response(PR), and 4 cases were no response(NR); Total effective rate was 80%(CR and PR rate was 60% and 20% respectively); 5 cases relapsed in 3‐year follow‐up after CR1(41.7%), 3 of them achieved CR2 after re‐induction chemotherapy, and 2 cases remained NR. Among 20 cases of non‐M3, 1 case lost to follow‐up after diagnosis within 1 month. Mean followed‐up of 19 cases was 26.2 months(1.5‐84), those 9 cases died(6 cases of M5,1 case of M4 and 2 cases of M2),who achieved PR or NR or relapsed after CR1; The 3‐year DFS and OS were 21% and 31.5% respectively. 2 cases of non‐M3 who accepted allo‐HSCT with HLA‐matched sibling donor kept disease‐free survival until last visit with OS of 58 and 66 months respectively. Except for 3 cases of M3 and 2 cases who received allo‐HSCT, among other 18 cases, 11 cases with initial WBC count less than 10×109/L had longer OS and DFS than that of 7 cases with initial WBC count not less than 10×109/L(mean 36.2 vs 9.3, P=0.03; mean 24.5 vs 0.46, P=0.002). 12 patients who achieved CR1 had longer OS than those who did not(mean 32.42 vs 6.8, P=0.002). All the 3 cases of M3 with RARA gene kept survival until last visit. Among non‐M3 patients, those patients with anyone of FLT3(2 cases), MLL(1case) and HOX11(5 cases) had a poor prognosis while the patients either C‐kit(2 cases) or NPM1(2 cases) had preferable prognosis.Conclusion Trisomy 8 has a higher incidence in M5 than others AML sub‐type, and the prognosis of M5 was poor. The initial WBC count above 10×109/L is a high‐risk factor. Trisomy 8 may increase the risk of de nove AML except for M3, so allo‐HSCT with available HLA‐matched sibling donor after CR1 may be recommended. The gene mutation may have an important significance in prognosis.The patients of M3 with trisomy 8 and RARA gene mutation were sensitive to chemotherapy; The existence of trisomy 8 had no adverse effect on prognosis of M3 no matter with t(15,17) or not. M3 with trisomy 8 as well as RARA gene had a very good prognosis. The evolution of karyotype during the later course has a close relationship with progression of diseases. The patients of M3 with complex karyotype may have poorer prognosis.