Impact of systemic treatment on local control for patients with lymph node-negative breast cancer treated with breast-conservation therapy.
OBJECTIVE
To determine the impact of tamoxifen and chemotherapy on local control for breast cancer patients treated with breast-conservation therapy.


METHODS
The data from 484 breast cancer patients who were treated with breast-conserving surgery and radiation were analyzed. Only patients with lymph node-negative disease were studied to provide comparative groups with a similar stage of disease and a similar competing risk for distant metastases. Actuarial local control rates of the 277 patients treated with systemic therapy (128, chemotherapy with or without tamoxifen; 149, tamoxifen alone) were compared with the rates for the 207 patients who received no systemic treatment. Only 10% of the patients had positive (2%), close (3%), or unknown margin status (5%).


RESULTS
Patients treated with systemic therapy had improved 5-year (97.5% v 89.8%) and 8-year (95.6% v 85.2%) local control rates compared with those that did not receive systemic treatment (P =.004, log-rank test). There was no statistical difference in local control between patients treated with chemotherapy and patients treated with tamoxifen alone (P =.219). Systemic treatment, margin status, young patient age, estrogen and progesterone receptor status, and primary tumor size were analyzed in a Cox regression analysis. The use of systemic treatment was the most powerful predictor of local control: patients who did not receive systemic treatment had a relative risk of local recurrence of 3.3 (95% confidence interval, 1.5 to 7.5; P =.004).


CONCLUSIONS
In this retrospective analysis, systemic therapy appears to contribute to long-term local control in patients with lymph node-negative breast cancer treated with breast-conservation therapy.
Buchholz
T A
TA
Departments of Radiation Oncology, Biomathematics, Breast Medical Oncology, and Surgical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA. tbuchhol@mdanderson.org
Tucker
S L
SL
Erwin
J
J
Mathur
D
D
Strom
E A
EA
McNeese
M D
MD
Hortobagyi
G N
GN
Cristofanilli
M
M
Esteva
F J
FJ
Newman
L
L
Singletary
S E
SE
Buzdar
A U
AU
Hunt
K K
KK
D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery*; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D013629:Tamoxifen / Q000627:therapeutic use*; D016896:Treatment Outcome
D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen