The significance of extracapsular extension of axillary lymph node metastases in early-stage breast cancer

Purpose: To investigate if extracapsular extension (ECE) of axillary lymph node metastases predicts for a decreased rate of disease-free survival or a n increased rate of regional recurrence of breast carcinoma. Methods: The study population consisted of 368 patients with T1 or T2 breas t cancer and pathologically-positive lymph nodes treated with breast-conser ving therapy between 1968 and 1986, The median number of sampled lymph node s was 10, Median follow-up time for the surviving patients was 139 months ( range 70-244), Twenty percent of the patients were treated with supraclavic ular RT, and 64% received both axillary and supraclavicular RT, with a medi an dose to the nodes of 45 Gy, The following factors were evaluated: presen ce of ECE, number of sampled lymph nodes (LN), number of involved LN, size of primary tumor, histologic grade of tumor, presence of lymphatic vessel i nvasion (LVI), presence of an extensive intraductal component (EIC), radiat ion dose, use of adjuvant chemotherapy, and age of patient. Recurrences wer e reported as the 5-year crude sites of first failure, and were divided int o breast recurrences (LR), regional nodal failure (RNF, defined as isolated axillary, supraclavicular, or internal mammary recurrence), and distant me tastases (DM), Results: One hundred twenty-two patients (33%) had FCE and 246 patients did not. The median number of LN with ECE was 1 (range 1-10) and 20% of patien ts had ECE in greater than or equal to 4 LN, Patients with ECE tended to be older (median age 51 vs. 47, p = 0.01), and had a higher number of involve d LN (median 3 vs. 2, p = 0.005) than patients without ECE, Forty-three per cent of patients with ECE had 2:4 involved LN compared to 15% of patients w ithout ECE (p < 0.0001). Models of ECE and the above factors revealed no si gnificant correlation between ECE and either disease-free or overall surviv al. There was no statistically significant increase in local, regional noda l, or distant failures in patients with FCE as compared to patients without ECE, Conclusion: In this population of patients with nodal involvement, the pres ence of ECE correlates with the number of involved LN but does not appear t o add predictive power to models of local, regional, or distant recurrence when the number of positive LN is included. (C) 2000 Elsevier Science Inc.