BACH CAU CAP TIEN TUY BAO 6 TRE EM:
NHAN MOTTRl/QNG HgP LUI BENH HOAN TOAN SAU DIEU TRI BANG ALL-TRANS RETINOIC ACID
(ATRA) TAI KHOA NHI - BENH VIEN BACH MAI
Nguyen Van Bang*, Can Tuyet Nga**, Le Thj Lan Anh*, Nguyen Tien Dung***
TOM T A T
Bgch cdu cdp the tiin tuy bdo (acute promyelocytic leukemia: APL) la mot phdn nhom rieng biet cita bgch can cdp the tiiy vd co nhieu dgc tinh rieng biet ve dien bien vu ddp img dieu tri. Benh chu yeu gap a ngtrdi lan Ire tudi. rdt il giup o tre em dtrdi 10 tudi. Thanh lini lim nhdt trong dieu tri APL nhimg ndm gdn day Id nhd lien bo ve di truyen hgc nen dd phdt hien dirge 6 gene dieu hod long hpp protein alpha thy the ciia acid retionic trong benh APL (APL/RARA) Idm ca sa khoa hoc cho viec dieu tri hdng all trans- retinoic acid (ATRA) trong benh ndy. Viec phdt hien sam vd khang dinh chdn dodn bdng xet nghiem di tritven hoc. sir dimg sdm cdl-trans retinoic acid (ATRA) vd dp diing day du cdc bien phdp dieu tri hd trg tich circ vd dimg dan dd lam thay ddi hoan todn tien hrong henh cua APL. tir mot the henh khdng chira dtrgc vd tir vong nhanh chong do roi logn ddng mdu nirng thdnh mgt henh cd the lui henh hoan loan vd hen vimg. Tgi Viet Nam den nay chua thciv co thong bdo ve dieu tri APL hdng ATRA a tre em. Chimg loi thong bdo mgt tnrdng hgp benh nhdn 6 tuoi bi APL dieu tri bimg ATRA vu huu chdi dgi dugc lui henh houn todn suu mat giai dogn ciiv ky nirng do giam bgch cdu hgt ddn den nhiem khudn mdu, nham chia se mgt so thong tin cimg cdc dong nghiep ve the benh dgc biet nay.
Ttr khoa: bgch cdu cup lien tuy hao (APL). gene dieu hod tdng hgp protein ulphu (PML/RARA) . ull-truns retinoic acid (ATRA). tre em.
I. DAT VAN DE
Bach cau cap the tien tuy bao (acute promy- elocytic leukemia: APL, thudng dtroc ggi la the M3 trong bang phan loai Phap-My-Anh) la mdt phan nhom riSng biet trong bach cau cap the tiiy va co nhiSu dac tinh dac biet ve dien bien va tien lugng [I, 3]. Benh chii ySu gap d ngudi Idn tre tuoi, rat it gap d tre em dudi 10 tuoi [ I ]. Benh nhan bj APL eo the tir vong nhanh chdng trong benh canh xuat huyet 6 at, nhirng lai co the lui benh hoan toan va ngoan muc neu diSu trj kip thdi va dting dan [ 1,6,9]. Thanh tyu Idn nhat trong diSu trj APL nhirng nam gan day nhd nhirng tien bg ve di truyen hpc, cho phep phat hien d gene dieu boa tong hgp protein alpha thu thS ciia acid retionic trong benh APL (viet tit la APL/
RARA) lam ca sd khoa hgc cho viee dieu trj blng
all trans-retinoic acid (ATRA) trong the benh nay [2, 3]. Viec phat hien sdm va khang djnh chan doan bang ket qua xet nghiem di truyen hgc, sir dung all- trans retinoic acid (ATRA) va ap dung day dti eac bien phap dieu trj hd trg tich eye va dimg dan da lam thay doi hoan toan tien lugng benh ciia APL, tu mpt the benh khdng chira dugc va tir vong nhanh chdng do roi loan dong mau thanh mgt benh chua khoi (lui benh hoan toan va ben vCrng) [4-7, 9, 10]. Tai Viet Nam, ATRA da dtrgc sir dung dieu trj APL d ngudi Idn ttr vai nam nay vdi ket qua rat dang khich le. Tuy nhien, chua thay cd thdng bao nao ve ket qua dieu tri APL bang ATRA d tre em. Khoa Nhi, Benh vien Bach Mai vita cd djp tiep nhan va dieu tri mdt benh nhin APL lui benh holn toan sau mdt giai doan cue ky nang do giam bach cau hat dan dSn nhiem khuan
*Bd mdn Nhi, DH Y Hd Ndi: **Khoa Dirge - BV Bgch Afai; *** Khoa Nhi - BV Bgch Mai
56 47 (Thang 12/2009) Y HOC LAM SANG
I 13
mlu. Chimg toi xin thdng bao trudng hpp nay nham chia se mot so thong tin cting cac dong nghiep ve the benh dac biet nay.
Thong bao trudng hgp lam sang
Benh nhi Nguyen Dinh Th. nam, 6 tuoi, vao khoa Nhi - Benh vien Bach Mai ngay 8/6/2009 vi xanh xao, nhieu cham xuat huyet tren da va chay mlu cam ttr hon mpt thang.
Khum khi vao: tre thieu man nang, met, co nhieu cham-not-mang xuat huySt rai rac tren da;
chay mau cam nhiSu lan. Gan to (3 cm), laeh hach khong to. Khong co cac biSu hien nhiem khuan tren lam sang va can lam sang.
Cong thiic mim (CTM) hie vuo vien (H./6/09):
hong cau (HC) 3,46 T/l, Hb: 101 g/l, tiSu cau (TC):
17 G/l, so lugng bach cau (BC): 3,48 G/l trong do ty IS da nhan trung tinh (TT): 24,7% (0,86 G/l), lym- pho (L): 54,3% (1,89 G/L), mono (M): 2 1 % (0,73 G/l). Khong thay xuat hien cac te bao non (blast) d mau ngoai vi.
Tuy do (tai Benh vien Nhi Trung uong ngay 21/5/09): so lugng te bao tuy: 23.800/mm\ blasts (pro- myeloblast): 65%, TT: dua: 1%, nhieu miii: 10%, ua
acid: 1%, L: 20%, HC ua acid: 3%, HC Itrdi: 2%.
Khdng thly nguySn mau TC va mau TC tren tuy do.
Peroxidase (+).
Ket lugn: BCC the tien tuy bao (M3)
Tien trien va dieu trj tai khoa Nhi - Benh vien Bach Mai
Ttr ngay 8/6/09: sdt nhe (T: 37,5-38°C), CRP: 0,1 mg/dl. Ket qua ve ddng bach cau trong mau ngoai vi qua cac lan xet nghiem mlu dupe trinh bay trong bang I.
Benh nhi dugc diSu trj bang: ceftriaxone (9 ngay) tiep den ceftazidim (6 ngay) phoi hgp vdi gentamycin. Ddng thai tre dugc dieu tri bang Meth- ylprednisolone 2mg/kg (15 ngay). Trudng hgp lam sang, benh nhan khdng c6 cae bieu hien roi loan dong mau nang de doa tinh mang. Xet nghiem dong mau CO' ban (19/6/09) rdi loan mirc dp nhe: ty le prothrombin: 89,4%, thdi gian prothrombin (PT):
12,2 giay, APTT: 22,7 giay (chimg 28,3 giay), PT- INR: 1,06, nghiem phap rugu: duo'ng tinh (+++), thdi gian tiSu euglobulin (Von-Kaula) >60 (chuan
>60), D-Dimmer: 2.460 ug/l (binh thudng: 125-345 ug/I), fibrinogen: 1,06 g/l (binh thudng 2-4 g/l).
Bdng 1. Ket qud ve dong bqch cdu trong mdu ngoai vi
BC(G/1)
TT (% va tuyet ddi) Blast (%)
8/6 3,5 25% (850)
0
12/6 2,1 4% (80)
67
16/6 5,0 6% (300)
66
19/6 8,4 3% (240)
72
21/6 12,8 14% (1800)
69
Den ngay 23/6/09: tre sdt eao 39-39,5°C, da rat xanh, chay mau cam nhieu lan, rat met, xuat huySt dudi da da hinh thai. Xet nghiem cho thay:
HC: 1,5 T/I, Hb: 96g/l, TC: 15 G/l, BC: 12,1 G/I:
TT: 5% (600/mm^), L: 9%, Blasts: 86%.
Tre dirge dimg hod tri lieu tdn cdng tir 24/6, gdm:
- Cytarabin (Alexan) 70mg, truySn TM 30 phiit.
- Daunorubicin (Daunoblastin) 30ing, truySn TM 30 phut.
- Etoposide lOOmg, truySn TM 30 phiit.
- Dexamethason 4mg IV.
Dieu tri hd tra:
- Bicarbonate 500ml + G5% 500 ml. Ringer 500ml.
- Allopurinol udng.
- Truyen mau nhieu lan.
- Ceftazidim TM.
Dien biin fir 30/6 (sau 1 tudn hod trj lieu): sdt 38°5- 39°C, thiSu mau nang, met nang.
CTM: HC: 2,46 T/l, Hb: 73g/l, BC: 0,23 G/l, TT 9,2% (20 te bao/mm').
-Ngirng hoa trj lieu.
- c l y mau, CTM, CRR
- Cefoperazon + Sulbactam 5 ngay sau thay blng
14 I
Y H O C L A M S A N G 36 47 (Ttiang 12/2009)Meropenem (24 ngay) + Gentamycin + Sulfame- thoxazol - Trimetoprim.
- Filgrastim (Leucokin) 1 mg/kg dudi da, 15 ngay (7/7 dSn 21/7).
- Dieu tri ho trg: truyen mau, allopurinol, truyen Ringer va bicarbonate (2.000mi/24h).
Ket qua cay mau lan dau (ve ngay 3/7):
E. coli, nhay cam vdi Cefobactam (cefoperazon- sulbactam, Meropenem, Fosfomycin va Amikacin.
Benh nhan dugc thay Cefobactam (cefoperazon- sulbactam) bang Meropenem phoi hgp vdi Fosfo- mycin va Amikacin.
Ket qua cay mau lan 2 sau 4 ngay (7/7) va lan 3 mpt tuan sau do (14/7) deu am tinh.
Cac xet nghiem CTM (6/7): HC: 1,4 T/l, Hb 42 g/l, BC: 0,28 G/l, TT: 25% (70 BCTT/mm^), TC: 6,0 G/l, va ngay 17/7, BC: 2,54 G/l, TT: 65%
(1,650), HC: 1,6 G/l, Hb 49g/l, TC: 69 G/l.
Tre bat dau dugc dting ATRA ttr ngay 17/7 vdi liSii lOmg (25mg/m-/24h) lieu duy nhat trong ngay, lien tuc den nay (ke hoach dieu tri dti 52 tuan).
Ngirng KS (20/7) (sau 24 ngay dting Mero- penem): sau 2 tuan khdng sdt va 2 lan cay mau (-).
Ngimg Filgrastim (21/7), sau 15 ngay) khi BC 20,23 G/l (TT: 56%, 12,000), HC 2,4 T/l, TC: 153 G/l).
Ket qua cac xet nghiem mau ngoai vi dyoe trinh bay trong bang 2.
Bdng 2. Ket qud cdc xet nghiem mdu ngoai vi Cac thong so
BC (G/l) TT (%) Blast (%) HC (T/l) Hb (g/l) TC (G/l)
7/8 5,4 72,4
0 2,6 75 459
14/8 8,5 87,5
0 2.8 83 292
24/8 11.5 67,0 0 3.6 106 438
- Tuy do (28/8): lui benh hoan toan.
Ttr ngay 31/7 khi BC 11,0 G/l (TT: 60%, Blast 8%): ben canh ATRA, tre dugc dieu tri lai bang Daunorubicine va Cytarabine. Tuan tiep theo do, xuat hien sot dao dpng (3-5 can/ngay) 39°-40°C, sirng dau mat trong diii phai, mat dudi canh tay phai gan nach, sau vai ngay sung thSm cang tay phai. Tre dugc chan doan la viem co/ap-xe co (nghi do tu cau vang, dti kSt qua cay mau ve am tinh). Dap irng tdt vdi dieu trj khang sinh, tien triSn tot sau 8 ngay dieu trj phoi hgp Bristopen va Amikacin.
Benh nhan xuat vien ngly.... (hinh I va 2), tiep tuc udng ATRA theo dy kiSn dii 12 thang. Tai khlm, nhap vien, kiem tra tuy dd trudc khi bit diu lieu trinh duy tri 6 thang cho kSt qua tuy dd hoan toan binh thudng.
Bat dau lieu trinh ciing c6 mdi thang I dpt (Cytarabin 200ing/m2/ngay chia 2 lln tiem dudi da hoac TM chia 2 lan trong 5 ngay, va Doxorubicin
45mg/m2 TM, I lieu duy nhat moi dot). Hien da qua 2 dpt dieu trj cimg co. Tinh trang lam sang rat tot, xet nghiem mau ngoai vi hoan toan binh thudng.
Tuy do trirdc dieu trj cimg cd thang thir 2: hoan toan lui benh.
IL NHAN XET VA B A N LUAN
Do dac diem riSng biet vS benh canh lam sing va kha nang dieu tri ngoan miic cita benh APL, benh can dugc khang djnh chan doan sdm, khdi dau dieu tri dac hieu bang hoa chat va ATRA phoi hgp vdi cham sdc dac biet dS ciru song va chira khdi benh nhan. Tuy nhien, cho den nay d nude ta, gia dinh vl thay thuoc thudng co thai do thit vpng va
"budng xudi" trirdc benh nhan bi the benh BCC the tuy noi ehung, ke ca APL vi von dinh kien la BCC the tuy tien lugng qui xau, it khi nang cuu song. Vi vay, thong qua trudng hop benh nhan Th., ciing vdi nhung nhung thong bio ngay clng nhieu vS ket qua
56 47 (Ttiang 12/2009) Y HOC LAM SANGI 15
ngoan muc trong dieu trj APL trSn the gidi, chimg toi mu6n giri den cac ddng nghiep mot thong diep mdi: APL Id mgt the henh nirng nhimg co the chiru khoi (hd benh) houn todn: vi vgy. cdn dugc chdn dodn sow bimg hinh thui hgc (tuy do), khdng dinh hcmgxel nghiem di truyen hgc (phdt hien gene APL/
RARA) vu dii'u cup cim bdng hod chdt phoi hgp vdi tluinc diic hii'ii lu .4TP4 vu chum soc tich circ nhir thdng le Irong dieu tri henh BCC hdng hod chut noi chimg.
Benh nhan Th. rat may man la dti khdi dau dieu trj mupn (hon 1 thang kS ttr khi chan doan) va chi dugc dieu trj bang ATRA sau dpt suy tuy sau diSii tri hoa chat nhung khong bi roi loan dong mlu nang gay tir vong nhanh chdng ngay khi chua kjp diSu tri hoa chat nhu cac trudng hgp APL van thtrdng gap.
Day la sy may man hi huu khong de gap, nen can nit kinh nghiem cho nhung benh nhan sau, nham tranh bien chirng nii ro ve rdi loan dong mau co thS gap bat cir benh nhan nao. Mat khac, hien tugng suy tuy nang khi vtia mdi khdi dau dieu trj hoa chat va hau qua ciia giam bach cau hat nang la nhiem khuan huyet do E.coli da thyc sy de doa tinh mang benh nhi trong nhirng ngay dau. Viec sir dung phoi hgp cac khang sinh mdi. phd rpng vdi thude kich thich sinh dong te bao tuy (Filgrastim ma biet duge la Leucokin) keo dai va diSu trj hd trg tich cue bang truyen mau va tieu cau nhieu lan, tang cudng dao thai dgc chat npi sinh (tang bai nieu bang truySn djch khoi lugng Idn, kiem hoa nudc tieu, sir dung allopurinol), dam bao dinh duong nang lugng cao, de phong viem phoi do Pneumocystis carrinii bang Bactrim da cho phep benh nhan thoat khoi de dga tir vong. Viee khdi dau dieu trj bang ATRA d benh nhan nay ciia chiing tdi bj tri hoan mpt phan do tinh trang nhiem khuan huyet, nhung mpt phan con do lan dau tiSn nen chua co kinh nghiem. Tuy vay, sy lui benh holn toan va keo dai trong tnrdng hgp nay cd IS chinh la do hieu qua ciia viec su dung ATRA phdi hgp vdi cle hoa chat chdng phan bao van dugc dting ttr trti'dc den nay. Benh nhan ctia chiing tdi chua duac xet nghiem gene APL/RARA trudc dieu
tri va khi lui benh nhirng co s6 lugng bach eau trong ] mau ngoai vi thap <10.000/mm^ va nhat la cd sy dap >
irng ngoan muc vdi /VTRA cho phep tien doan nguy j CO' tai phat thap. -
Dieu lam nen sy khac biet giira APL vdi cae the khac ciia BBC the tuy la trong APL co sy bat thirdng dac trung ve chuyen doan nhiem sac the j (NST) t [15:17]. Chinh sy chuyen doan nay eo lien : quan chat che vdi thii the ctia acid retinoic va dan dSn sy san xuat ra protein alpha thu the acid retinoic cita APL (APL/RARA: acute promyelocytic leuke- mia/retinoicacid receptor alpha) [1-3]. CactSbaoac | tinh d benh nhan APL eye ky nhay cam vdi tac dung \ gay biet hoa ctia all-trans retinoic acid (ATRA). Ca sd khoa hgc ciia viec dieu tri bang /VFRA trong APL | la cung cap mpt lieu acid retinoic co tac dung dugc i ly de giiip ca the vupt qua dugc sy irc che thong | tin di truyen ma protein sinh ra ttr gene APL/RARA ' tao ra trong dieu kien ma nong do acid retinoic chi d mirc sinh ly. Mpt khi tin hieu da dugc phuc hoi, ; cac te bao non se trudng thanh va chSt sinh ly [3, 4]. Ve mat xet nghiem di truyen hpc, viec bien mat i CLia gene APL/RARA tren chudi RNA cudi dpt dieu j tri qua RT-PCR (reverse-transcription-polymerase \ chain reaction) cho phep tien lugng tot vi rat it kha •
nang tai phat [1-3]. i Dac trung ve lam sang ciia APL la sy roi loan j
i
ddng mau tram trpng xay ra trong giai doan dau ctia I benh va nang ISn dot ngot hon nhiSu khi bat dau dieu trj tan cdng bang hoa chat so vdi cac the lam sang j khac ciia BCC the tuy [I]. Mat khac, do dac tinh rat it khi tham nhiem vao he than kinh nSn khong 1 can phai kiSm tra djch nao tuy khi mdi chan doan va
ciing khdng can diSu trj hoa chat npi tuy [ I ]. ; Da sd benh nhan APL se lui benh holn toan
khi dugc diSu trj bang ATRA, dii rang mgt minh ATRA khdng dii dS chiia khdi benh [I, 5-8]. NhiSu \ nghien cii'u thti' nghiSm lam sang ngau nhien eho i thly Igi ich ciia viec phdi hgp dieu trj hoa chit vdi | ATRA [7, 8. 10] ciing nhu tie dung ciia ATRA trong dieu trj duy tri [I, 4-6]. Ty IS lui benh hoan toan d ; tre em bj APL da vugt qua 80% ttr khi ap dung phac I
16 I
Y HOC LAM SANG S6 47 (Ttiang 12 / 2009)do dieu tri sdm, phoi hgp hoa chit vdi ATRA va dieu trj ho trg manh me kSt hgp vdi chain soc tich eye (1,5-10). Cimg nhu APL d ngudi Idn, APL d tre em se co tien lugng tot hon neu so lugng bach can trong mau ngoai vi thap<IO.OOO/mm^ Nhung vi tre em bj APL hay gap the tang bach cau >10.000/inm^
nen tien lupng ehung khong tdt bang d ngudi Idn.
dac biet neu cd bien dj FLT3 thi kha nang tien lugng cang xau ho'n.
Hien nay, trudng phai Bac My dting phac dd dieu tri chuan cho tre em bi APL la dting ATRA cang sdm cang tot phoi hgp vdi cytarabine va daunorubi- cin liSu thong thudng trong dieu trj tan cdng; ciing CO bang ATRA phoi hgp vdi daunorabiein: duy tri bang ATRA ciing 6MP va methotrexate thay tot hon duy tri bang ATRA do'n thuan d benh nhan la ngudi Idn [8]. Tnrdng phai Italia va chau Au dting phac do tan cong bang ATRA phdi hgp vdi idarubicin ma khong diing cytarabine d tre em va eiing cd bang ATRA va mpt anthracycline (idarubicin va mitoxan- trone) [1,7]; dieu tri cimg cd giong nhu phac do Bac My.
Vi kha nang tai phat thap, nSn khdng co chi djnh ghep tS bao ngudn d nhung benh nhan lui benh dpt dau. Ngay ca vdi nhu'ng benh nhan tai phat. dieu
TAI LIEU THAM K H A O
trj lai bang hoa chat vdi phac do cd arsenic trioxide la thude dung nap tot d trS em cho phep dat ty le lui benh >85%. Phoi hgp arsenic trioxide vdi ATRA ed thS dat ty IS lui benh >90-100% d ca tre em va ngudi Idn [10].
i n . KET LUAN
Sy phat hien gene APL/RARA va hieu qua dieu tri ciia ATRA da lam thay doi han tien lugng benh bach cau cap the tien tuy bao. DS ciru sdng benh nhan, can khang djnh benh sdm bang tuy do va xet nghiem di truyen hpc dS chi djnh dieu trj ATRA sdm, trudc khi dting hoa chat dS tranh tir vong do rdi loan dong mau nang. Trudng hgp benh nhan dieu trj tai khoa chiing tdi la trudng hgp APL d tre em dau tiSn tai Viet Nam dtrgc diSu trj bang ATRA. Thdi gian theo doi cdn ngan, nSn chua thS xac dinh khdi benh, nhung sy dap irng tdt vdi diSu tri hoa chat thdng thtrdng phdi hgp vdi ATRA cho thay trien vgng rat kha quan trong dieu trj benh nay. Chiing ta ciing can co mpt phac do hudng dan diSu trj rieng thdng nhat cho thS benh nay d tre em Viet Nam de nhanh chdng cd tong ket kinh nghiem trong toan quoc*
1. Sanz MA. Griimvade D. Tallman MS, et cd.: Management of acute promyelocytic leukemia: Recommenda- tions from an expert panel on behalf of the European LeiikemiaNet. Blood 2009, 113f9):I875-]89] (prepub- lished online Sep 23, 2008).
2. Gameiro P. Vieira S. Carrara P, et al.: The PML-RAR alpha transcript in long-term follow-up of acute pro- myelocytic leukemia patients. Haematologica 86 (6): 577-85, 2001.
3. Jurcic JG, Nimer SD, Scheinberg DA, et al.: Prognostic significcmce of minimal residual disease detec- tion and PML/RAR-alpha isoform type: long-term follow-up in acute promyelocytic leukemia. Blood 98 (9):
2651-6, 2001.
4. Altucci L, RossinA, Raffelsberger W, et al.: Retinoic acid-induced apoptosis in leukemia cells is mediated by paracrine action of tumor-selective death ligand TRAIL. Nat Med 7 (6): 680-6, 2001.
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7. Ortega J.I. Madero L. Martin G. et ul.: Treutment with all-trans retinoic acid and anthracycline mono- chemotherupy for children with ucute promyelocytic leukemiu: a midticenter study hy the PETHEMA Group.
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SUMMARY
ACUTE PROMYELOCYTIC LEUKEMIA(APL) IN CHILDREN: APROPOS OF ONE CASE OF APL WITH COMPLETE REMISSION UNDER ATRRA IN PEDIATRIC DEPARTMENT, BACHMAI HOSPITAL
• Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloid leukemiu (AML) and is treated differently than other types of AML. Optimul treutment requires rapid initiation of treatment and sup- portive care measures. The churucteristic chromosomul uhnormulity associuted with APL is [15; 17]. This
trunslocatioii involves a hreukpoint thut includes the retinoid ucid receptor and that leuds to production of the promyelocytic leiikemia/retinoic acid receptor alpha (PML'RARA) fusion protein. The disease is very umcom- mon in children less than 10 years of age. Clinically, APL is commonly characterized by a severe coagulopa- thy often present at the time of diagnosis. Mortality during induction (with cytotoxic agents) due to bleeding complications is more common in this subtype than in other French-Americcm-British classifications. The leu- kemia cells from patients with APL are especially sensitive to the differentiution-indiicing effects of all-trans retinoic acid (ATRA). The basis fin- the drumutic efficacy of ATRA uguinst APL is the ubility of pharmacologic doses of ATRA to overcome the repression of signaling caused by the PML/RARA fusion protein at physiologic ATRA concentrations. Restoration of signaling leads to differentiation of APL cells and then to postmaturalion apoptosis. Most patients with APL achieve a complete remission when treated with ATRA. though single-agent ATRA is generally not curative. A series of randomized clinical trials has defined the benefit of combining ATRA with chemotherapy during induction therapy and also the mil lly of using ATRA as maintenance therapy.
For children with APL, survival rates exceeding 80% are now achievable using treatment programs that pre- scribe the rapid iniliation of ATRA and appropriate supportive care measures.
So far in Vietnam, no pediatric case of APL that achieved complete remission under ATRA treatment was reported. We presented a case off-year child with APL achieved complete remission in our pediatric depart- ment. Bachmai ho.spital in purpose of shewing information and experience with our colleagues and raising the alert on the parculiur disease.
Key-words: acute promyelocytic leukemia, acute promyelocytic leiikemia/retinoic acid receptor alpha (PML/
RARA) fusion protein, all-trans retinoic acid, children. ' '
