Prognosis of Minimal Residual Disease in Bone Marrow, Blood and Lymph Nodes in Breast Cancer

Abstract

The most important factor affecting the outcome of patients with invasive cancers is whether the tumor has spread, either regionally (to regional lymph nodes) or systemically (to the bone marrow). However, a proportion of patients with no evidence of systemic dissemination will develop recurrent disease after primary therapy. Clearly, these patients had occult systemic spread of disease that was undetectable by methods routinely employed (careful pathological, clinical, biochemical and radiological evaluation). This early dissemination of tumor cells is known as occult metastases (or micrometastases). In addition, the success of adjuvant therapy is assumed to stem from its ability to eradicate occult metastases before they become clinically evident. Therefore, methods for the detection of occult metastases in patients with the earliest stage of cancer, i.e., prior to detection of metastases by any other clinical or pathological analysis, have received a great deal of attention. This chapter focuses on the detection and significance of occult metastatic cells in the peripheral blood bone marrow and lymph nodes of patients with breast cancer.