Gender and ethnic differences in chronic myelogenous leukemia prognosis and treatment response: a single-institution retrospective study.
BACKGROUND
In the last decade the importance of ethnicity, socio-economic and gender differences in relation to disease incidence, diagnosis, and prognosis has been realized. Differences in these areas have become a major health policy focus in the United States. Our study was undertaken to examine the demographic and clinical features of chronic myelogenous leukemia (CML) patients presenting initially at the LAC+USC Medical Center, which serves an ethnically diverse population.


RESULTS
Patients were evenly split by gender, overwhelmingly Hispanic (60.9%), and quite young (median age 39, range 17-65) compared with previously reported CML patient populations. Previous CML studies identified significant anemia (Hgb <12 g/dl), significant thrombocytosis (platelets >450 x 109/l), and significant leukocytosis (WBC >50 x 109/l) as significant adverse pretreatment prognostic factors. Using these indicators, in addition to the validated Hasford and Sokal scores, patients were stratified and analyzed via gender and ethnicity. A significantly greater proportion of women presented with significant anemia (p = 0.019, Fisher's exact test) and significant thrombocytosis (p = 0.041, Fisher's exact test) compared to men, although no differences were found in risk stratification or treatment response. MCV values for women were significantly (p = 0.02, 2-sample t-test) lower than those for men, suggesting iron deficiency anemia. Focusing on ethnicity, Hispanics as a whole had significantly lower Hasford risk stratification (p = 0.046, Fisher's exact test), and significantly greater likelihood (p = 0.016, Fisher's exact test) of achieving 3-month complete haematological remission (CHR) compared with non-Hispanics at LAC+USC Medical Center, though differences in treatment outcome were no longer significant with analysis limited to patients treated with first-line imatinib.


CONCLUSIONS
Female CML patients at LAC+USC Medical Center present with more significant adverse pre-treatment prognostic factors compared to men, but achieve comparable outcomes. Hispanic patients present with lower risk profile CML and achieve better treatment responses compared to non-Hispanic patients as a whole; these ethnic differences are no longer significant when statistical analysis is limited to patients given imatinib as first-line therapy. Our patients achieve response rates inferior to those of large-scale national studies. This constellation of findings has not been reported in previous studies, and is likely reflective of a unique patient population.
Lee
Justin P
JP
Keck School of Medicine, University of Southern California, Los Angeles, California, USA. justinpl@usc.edu
Birnstein
Elliott
E
Masiello
David
D
Yang
Dongyun
D
Yang
Allen S
AS
D000293:Adolescent; D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005006:Ethnicity / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000175:diagnosis* / Q000453:epidemiology / Q000208:ethnology / Q000628:therapy*; D015141:Los Angeles / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012107:Research Design; D012189:Retrospective Studies; D012727:Sex Characteristics; D016896:Treatment Outcome; D054928:Validation Studies as Topic; D055815:Young Adult