Retrospective Study of Women Presenting with Axillary Metastases from Occult Breast Carcinoma

Although palpable axillary lymphadenopathy is most often related to benign disorders, it may be a harbinger of an underlying advanced malignancy. Fewer than 1% of patients diagnosed with breast cancer initially present with axillary metastases as their only clinical manifestation. This study represents the Mayo Clinic experience with women with occult breast cancer who presented with axillary metastases. Among a group of 44 women undergoing axillary biopsy for a palpable mass, 35 had histologic evidence of a metastatic carcinoma of primary breast cancer origin. Our retrospective analysis focused on the workup, identification, treatment, and outcome of these 35 women. All 35 women had a palpable axillary nodule, no dominant breast mass, and normal mammograms and chest radiographs. Histologic analysis of the axillary node revealed a probable breast cancer in all patients. Long-term follow-up was available for 33 patients (mean 71.5 months, range 4–252 months). Mastectomy was performed as part of the primary treatment in 18 patients (51%), and among them a primary breast tumor was found in 6 (33%). Of the women who underwent mastectomy (n = 18) and for whom follow-up data were available (n = 17), six developed tumor recurrence (35%), and four died of their disease (24%). Among the patients who did not undergo mastectomy (n = 17) as their primary treatment, follow-up revealed that 12 (of 16) patients developed recurrent disease (75%), and 11 patients died of breast carcinoma (69%). Despite extensive clinical and radiologic evaluation, a primary tumor was not initially located in any of the 35 women with axillary metastases from a presumed occult breast carcinoma. As a consequence of aggressive surgical intervention, six primary breast cancers were located in mastectomy specimens, and those 17 patients followed after mastectomy fared significantly better than the 16 patients without mastectomy (p = 0.047).