Micrometastases in axillary lymph nodes and bone marrow of lymph node-negative breast cancer patients--prognostic relevance after 10 years.

The long-term prognostic significance of immunohistochemically detectable occult tumor cells in bone marrow and axillary lymph nodes of breast cancer patients considered to be lymph node-negative in multilevel haematoxylineosin (H&E) lymph node sectioning was analyzed. A total of 212 patients with a median follow-up of 10.3 years were included in the study. Bone marrow was obtained during surgery and stained with anti-cytokeratin and anti-EMA antibodies. Additional consecutive sections of lymph nodes were stained either with H&E or with anti-cytokeratin antibodies. All histological sections were analyzed by the same pathologist. Micrometastases were detected in bone marrow of 67 (32%) patients. Immunohitochemical examination of negative axillary lymph nodes--based on multilevel H&E examination--revealed micrometastases in 14 (7%) cases. There was no difference in overall or disease-free survival between patients with or without epithelial cells in bone marrow. Immunohistological examination of axillary lymph nodes also did not add any prognostic information for overall or disease-free survival. However, patients with occult micrometastases in axillary lymph nodes had a slightly higher rate of local recurrences. Immunohistochemical analysis of bone marrow or axillary lymph nodes does not add prognostic information if multilevel H&E sectioning is performed. Therefore, decision about adjuvant therapy in breast cancer patients considered to be lymph node-negative in multilevel H&E microscopy should not be based on immunohistochemical detection of micrometastases in bone marrow or axillary lymph nodes.