Association of Low-Dose Aspirin and Survival of Women With Endometrial Cancer.
OBJECTIVE
To examine the survival outcomes in women with endometrial cancer who were taking low-dose aspirin (81-100 mg/d).


METHODS
A multicenter retrospective study was conducted examining patients with stage I-IV endometrial cancer who underwent hysterectomy-based surgical staging between January 2000 and December 2013 (N=1,687). Patient demographics, medical comorbidities, medication types, tumor characteristics, and treatment patterns were correlated to survival outcomes. A Cox proportional hazard regression model was used to estimate adjusted hazard ratio for disease-free and disease-specific overall survival.


RESULTS
One hundred fifty-eight patients (9.4%, 95% confidence interval [CI] 8.8-11.9) were taking low-dose aspirin. Median follow-up time for the study cohort was 31.5 months. One hundred twenty-seven patients (7.5%) died of endometrial cancer. Low-dose aspirin use was significantly correlated with concurrent obesity, hypertension, diabetes mellitus, and hypercholesterolemia (all P<.001). Low-dose aspirin users were more likely to take other antihypertensive, antiglycemic, and anticholesterol agents (all P<.05). Low-dose aspirin use was not associated with histologic subtype, tumor grade, nodal metastasis, or cancer stage (all P>.05). On multivariable analysis, low-dose aspirin use remained an independent prognostic factor associated with an improved 5-year disease-free survival rate (90.6% compared with 80.9%, adjusted hazard ratio 0.46, 95% CI 0.25-0.86, P=.014) and disease-specific overall survival rate (96.4% compared with 87.3%, adjusted hazard ratio 0.23, 95% CI 0.08-0.64, P=.005). The increased survival effect noted with low-dose aspirin use was greatest in patients whose age was younger than 60 years (5-year disease-free survival rates, 93.9% compared with 84.0%, P=.013), body mass index was 30 or greater (92.2% compared with 81.4%, P=.027), who had type I cancer (96.5% compared with 88.6%, P=.029), and who received postoperative whole pelvic radiotherapy (88.2% compared with 61.5%, P=.014). These four factors remained significant for disease-specific overall survival (all P<.05).


CONCLUSIONS
Our results suggest that low-dose aspirin use is associated with improved survival outcomes in women with endometrial cancer, especially in those who are young, obese, with low-grade disease, and who receive postoperative radiotherapy.
Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Southern California, and the Norris Comprehensive Cancer Center, Los Angeles, California; the Departments of Obstetrics and Gynecology, Tokai University School of Medicine, Kanagawa, Osaka University Graduate School of Medicine, Osaka, and Niigata University Graduate School of Medicine, Niigata, Japan; and the Departments of Gynecologic Oncology and Cancer Biology and the Center for RNA Interference and Non-Coding RNAs, the University of Texas MD Anderson Cancer Center, Houston, Texas.
Koji
K
Matsuo
Sigita S
SS
Cahoon
Kosuke
K
Yoshihara
Masako
M
Shida
Mamoru
M
Kakuda
Sosuke
S
Adachi
Aida
A
Moeini
Hiroko
H
Machida
Jocelyn
J
Garcia-Sayre
Yutaka
Y
Ueda
Takayuki
T
Enomoto
Mikio
M
Mikami
Lynda D
LD
Roman
Anil K
AK
Sood
D000230:Adenocarcinoma / Q000453:epidemiology / Q000473:pathology / Q000628:therapy; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D001241:Aspirin / Q000627:therapeutic use*; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology*; D004305:Dose-Response Relationship, Drug; D016889:Endometrial Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000628:therapy; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000453:epidemiology*; D006973:Hypertension / Q000453:epidemiology*; D007564:Japan / Q000453:epidemiology; D008875:Middle Aged; D009367:Neoplasm Staging; D009765:Obesity / Q000453:epidemiology*; D012189:Retrospective Studies; D013223:Statistics as Topic; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D001241:Aspirin