Management of contralateral axillary lymph node metastasis from breast cancer: a clinical dilemma.

AIMS AND
BACKGROUND: Contralateral axillary lymph node metastasis (CAM) in breast cancer patients is uncommon and the source uncertain. Management is complicated when CAM occurs as the first event of relapse after treatment of the primary tumor, especially in the absence of metastatic disease elsewhere.
METHODS: We reviewed the records of all breast cancer patients treated during 1999-2012. All patients with pathologically confirmed metachronous CAM were included. The examined data were demographic characteristics, tumor features and management modalities. Data from an epidemiological report that described the pathological characteristics of breast cancer in China during 1999-2008 were employed to allow further comparison. Twenty-eight patients with CAM were included in the study; they comprised 0.81% of the total number of patients. The median patient age was 47 years (range, 27-60 years). Half of the initial breast cancers were located at inner and central sites. Initial cancers were generally locally advanced (stage III, 50%) and hormone receptor negative. Treatment modalities included axillary lymph node dissection (ALND), mastectomy, radiation, and chemotherapy (± targeted therapy).
RESULTS: After 29 months of follow-up, 25 patients had disease progression with a median progression-free survival of 10 months. Regional recurrence was most commonly seen at sites including bilateral breast, chest wall and superficial lymph nodes, accounting for 44% (n = 11) of patients who progressed. Median progression-free survival was prolonged in patients treated with radiotherapy (10 months vs 22 months). During the observation period, 13 patients died of disease progression. We found that CAM was associated with tumors with aggressive pathological features and had a poor prognosis.
CONCLUSION: CAM is most likely to be distant metastasis from the initial breast cancer through lymphatic drainage rather than regional metastasis from a new occult breast cancer. Comprehensive treatment including chemotherapy and radiotherapy can provide better control; however, ANLD alone is insufficient treatment and mastectomy is not recommended.