Does microgranular variant morphology of acute promyelocytic leukemia independently predict a less favorable outcome compared with classical M3 APL? A joint study of the North American Intergroup and the PETHEMA Group.
Few studies have examined the outcome of large numbers of patients with the microgranular variant (M3V) of acute promyelocytic leukemia (APL) in the all-trans retinoic acid era. Here, the outcome of 155 patients treated with all-trans retinoic acid-based therapy on 3 clinical trials, North American Intergroup protocol I0129 and Programa para el Estudio de la Terapéutica en Hemopatía Maligna protocols LPA96 and LPA99, are reported. The complete remission rate for all 155 patients was 82%, compared with 89% for 748 patients with classical M3 disease. The incidence of the APL differentiation syndrome was 26%, compared with 25% for classical M3 patients, and the early death rate was 13.6% compared with 8.4% for patients with classical M3 morphology. With a median follow-up time among survivors of 7.6 years (range 3.6-14.5), the 5-year overall survival, disease-free survival, and cumulative incidence of relapse for patients with M3V were 70%, 73%, and 24%, respectively. With a median follow-up time among survivors of 7.6 years (range 0.6-14.3), the 5-year overall survival, disease-free survival, and cumulative incidence of relapse among patients with classical M3 morphology were 80% (P = .006 compared with M3V), 81% (P = .07), and 15% (P = .005), respectively. When outcomes were adjusted for the white blood cell count or the relapse risk score, none of these outcomes were significantly different between patients with M3V and classical M3 APL.
Tallman
Martin S
MS
Memorial Sloan-Kettering Cancer Center, Department of Medicine, New York, NY, USA. tallmanm@mskcc.org
Kim
Haesook T
HT
Montesinos
Pau
P
Appelbaum
Frederick R
FR
de la Serna
Javier
J
Bennett
John M
JM
Deben
Guillermo
G
Bloomfield
Clara D
CD
Gonzalez
Jose
J
Feusner
James H
JH
Gonzalez
Marcos
M
Gallagher
Robert
R
Miguel
Jose D Gonzalez-San
JD
Larson
Richard A
RA
Milone
Gustavo
G
Paietta
Elisabeth
E
Rayon
Chelo
C
Rowe
Jacob M
JM
Rivas
Concha
C
Schiffer
Charles A
CA
Vellenga
Edo
E
Shepherd
Lois
L
Slack
James L
JL
Wiernik
Peter H
PH
Willman
Cheryl L
CL
Sanz
Miguel A
MA
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003561:Cytarabine / Q000008:administration & dosage; D003630:Daunorubicin / Q000008:administration & dosage; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D015473:Leukemia, Promyelocytic, Acute / Q000145:classification / Q000188:drug therapy* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy* / Q000473:pathology*; D012074:Remission Induction; D015996:Survival Rate; D016896:Treatment Outcome; D014212:Tretinoin / Q000008:administration & dosage; D055815:Young Adult
D003561:Cytarabine; D014212:Tretinoin; D003630:Daunorubicin