Postoperative irradiation in breast cancer patients with one to three positive axillary lymph nodes. Is there an impact of axillary extranodal tumor extension on locoregional and distant control?
OBJECTIVE
To evaluate the impact of extracapsular extension (ECE) on locoregional and distant control in breast cancer patients with one to three positive axillary lymph nodes treated with postoperative irradiation. As shown in literature, ECE is diagnosed in up to 30% of node-positive breast cancer patients. Consequences of ECE and prognosis of these patients are unclear.


METHODS
The medical records of 1,142 node-positive females with a carcinoma of the breast, postoperatively irradiated between 1994 and 2003, were retrospectively reviewed. Of the 274 patients presenting with one to three positive axillary lymph nodes, 91 (33.2%) showed ECE. While all patients were irradiated using tangential fields, only eight out of 274 patients received additional nodal irradiation.


RESULTS
Patients' mean age was 58.2 years (range, 28-96 years), and the mean observation period 42.9 months (range, 6.6-101 months). In 93.4% of patients, locoregional control was achieved. On multivariate analysis of metastases-free survival, the hazard ratios for ECE and histological grade 3 were 2.71 (95% confidence interval [CI], 1.316-5.581; p = 0.007) and 2.435 (95% CI, 1.008-5.885; p = 0.048), respectively. The 3-year and 5-year metastases-free survival rates for patients with ECE were 78% and 66%, compared to 90% and 87% in patients without ECE (p = 0.0048).


CONCLUSIONS
Locoregional recurrence remains low in breast cancer patients (one to three positive axillary lymph nodes +/- ECE) treated with surgery, adequate axillary dissection, and tangential field irradiation only. However, ECE is significantly linked to a considerable risk for subsequent distant failure.
Stranzl
Heidi
H
Department of Radiotherapy-Radiooncology, University Medical School, Graz, Austria. heidi.stranzl@meduni-graz.at
Ofner
Petra
P
Peintinger
Florentia
F
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001317:Austria / Q000453:epidemiology; D001365:Axilla; D001943:Breast Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000517:prevention & control*; D011182:Postoperative Care / Q000706:statistics & numerical data*; D011379:Prognosis; D018714:Radiotherapy, Adjuvant / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome