Comparison of clinical outcome of breast cancer patients with T1-2 tumor and one to three positive nodes with or without postmastectomy radiation therapy.
OBJECTIVE
The value of postmastectomy radiation therapy for breast cancer patients with T1-2 tumor and one to three positive nodes remains controversial. The purpose of this retrospective study was to compare the clinical outcomes of breast cancer patients with T1-2 and one to three positive nodes with and without postmastectomy radiation therapy.


METHODS
Between May 1990 and June 2008, of 318 breast cancer patients with T1-2 and one to three positive nodes who had undergone modified radical mastectomy, 163 received postmastectomy radiation therapy and 155 did not. The clinico-pathologic characteristics were analyzed for clinical outcomes including loco-regional recurrence, distant metastasis, disease-free survival and overall survival.


RESULTS
During the median follow-up period of 102 months, the clinical outcomes in postmastectomy radiation therapy versus no-postmastectomy radiation therapy groups were as follows: loco-regional recurrence rate (3.1 versus 11.0%, P= 0.006); distant metastasis rate (20.9 versus 27.7%, P= 0.152); 10-year disease-free survival rate (73.8 versus 61.3%, P= 0.001); and 10-year overall survival rate (82.1 versus 76.1%, P= 0.239). Through a multivariate analysis, a positive nodal ratio of ≥25% (hazard ratio= 4.571, P= 0.003) and positive lymphovascular invasion (hazard ratio= 2.738, P= 0.028) were found to be independent poor prognostic predictors of loco-regional recurrence. The reduction in loco-regional recurrence (hazard ratio= 0.208, P= 0.004) by postmastectomy radiation therapy was found to be significant.


CONCLUSIONS
On the basis of our results, postmastectomy radiation therapy is highly recommended for breast cancer patients with T1-2 and one to three positive nodes, especially for high-risk subgroups with a positive nodal ratio of ≥25% and positive lymphovascular invasion, not only for reducing loco-regional recurrence but also for improving disease-free survival.
Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan, Republic of China.
Chih-Jen
CJ
Huang
Ming-Feng
MF
Hou
Hung-Yi
HY
Chuang
Shi-Long
SL
Lian
Ming-Yii
MY
Huang
Fang-Ming
FM
Chen
Ou-Yang
OY
Fu
Sheng-Fung
SF
Lin
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008408:Mastectomy; D008875:Middle Aged; D009362:Neoplasm Metastasis; D018714:Radiotherapy, Adjuvant; D012008:Recurrence; D012189:Retrospective Studies; D016896:Treatment Outcome