Oophorectomy and tamoxifen adjuvant therapy in premenopausal Vietnamese and Chinese women with operable breast cancer.
OBJECTIVE
In 1992, the Early Breast Cancer Trialists' Collaborative Group reported that a meta-analysis of six randomized trials in European and North American women begun from 1948 to 1972 demonstrated disease-free and overall survival benefit from adjuvant ovarian ablation. Approximately 350,000 new cases of breast cancer are diagnosed annually in premenopausal Asian women who have lower levels of estrogen than western women.


METHODS
From 1993 to 1999, we recruited 709 premenopausal women with operable breast cancer (652 from Vietnam, 47 from China) to a randomized clinical trial of adjuvant oophorectomy and tamoxifen (20 mg orally every day) for 5 years or observation and this combined hormonal treatment on recurrence. At later dates estrogen- and progesterone-receptor protein assays by immunohistochemistry were performed for 470 of the cases (66%).


RESULTS
Treatment arms were well balanced. With a median follow-up of 3.6 years, there have been 84 events and 69 deaths in the adjuvant treatment group and 127 events and 91 deaths in the observation group, with 5-year disease-free survival rates of 75% and 58% (P =.0003 unadjusted; P =.0075 adjusted), and overall survival rates of 78% and 70% (P =.041 unadjusted) for the adjuvant and observation groups, respectively. Only patients with hormone receptor-positive tumors benefited from the adjuvant treatment. In Vietnam, for women unselected for hormone receptor status, a cost-effectiveness analysis suggests that this intervention costs $350 per year of life saved.


CONCLUSIONS
Vietnamese and Chinese women with hormone receptor-positive operable breast cancer benefit from adjuvant treatment with surgical oophorectomy and tamoxifen.
Love
Richard R
RR
University of Wisconsin Comprehensive Cancer Center, 610 Walnut Street, Madison, WI 53705-2397, USA. rrlove@facstaff.wisc.edu
Duc
Nguyen Ba
NB
Allred
D Craig
DC
Binh
Nguyen Cong
NC
Dinh
Nguyen Van
NV
Kha
Nguyen Ngoc
NN
Thuan
Tran Van
TV
Mohsin
Syed K
SK
Roanh
Le Dinh
le D
Khang
Hoang Xuan
HX
Tran
Trinh Luong
TL
Quy
Tran Tu
TT
Thuy
Nguyen Van
NV
Thé
Pham Nhu
PN
Cau
Ton That
TT
Tung
Nguyen Dinh
ND
Huong
Dang Thanh
DT
Quang
Le Minh
le M
Hien
Nguyen Ngoc
NN
Thuong
Le
L
Shen
Tian-Zhen
TZ
Xin
Ye
Y
Zhang
Qian
Q
Havighurst
Thomas C
TC
Yang
Yonghong Fred
YF
Hillner
Bruce E
BE
DeMets
David L
DL
D000328:Adult; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001365:Axilla; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000208:ethnology / Q000601:surgery*; D017024:Chemotherapy, Adjuvant; D002681:China / Q000453:epidemiology; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D009367:Neoplasm Staging; D010052:Ovariectomy; D017697:Premenopause; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D013629:Tamoxifen / Q000627:therapeutic use*; D016896:Treatment Outcome; D014744:Vietnam / Q000453:epidemiology
D018931:Antineoplastic Agents, Hormonal; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D013629:Tamoxifen