Importance of Missed Axillary Micrometastases in Breast Cancer Patients

Abstract

Axillary lymph node metastases dramatically worsen the prognosis of patients with breast cancer. Despite this prognostic significance, routine histologic examination of axillary lymph nodes examines less than 1% of the submitted material. It is therefore obvious that micrometastatic disease is missed with this rather cursory examination, and the question arises as to the significance of this missed disease. Most lines of evidence suggest that missed axillary micrometastases exist and contribute to patient mortality. Most large studies of breast cancer micrometastases have suggested that undetected axillary micrometastases can be identified with more detailed examinations of the regional lymph nodes and that this group of patients has a poorer prognosis than those with no metastases identified. In addition, small-volume nodal disease, too small to be detected by traditional hematoxylin and eosin staining, has been shown to be capable of producing tumors in animal models. Finally, micrometastases have been shown to be of significance in other diseases. This article reviews the lines of evidence and the ongoing studies that are attempting to clarify the significance of micrometastatic disease in patients with breast cancer.

Probing of breast cancer using a combination of plasma and urinary circulating cell-free DNA

“…The risk of disease relapse in patients with early-stage breast cancer is significant and, in part, may be attributed to missed micrometastases during diagnosis [ 16 ]. This highlights the need for more thorough monitoring of patients following the surgical removal of cancerous tissues.…”

Significance of micrometastases on the survival of women with T1 breast cancer

“…6 Although straightforward to define, the impact of lymph node micrometastases on survival remains an unresolved issue. [7][8][9][10] In initial series, women with micrometastases did not experience a survival disadvantage when compared with women with lymph node-negative breast cancer, 1,11,12 suggesting that micrometastases are not of major clinical interest.…”

The prognostic significance of micrometastases in node-negative squamous cell carcinoma of the vulva

“…In breast cancer, for example, the presence of micrometastases in axillary nodes is an independent and a significant predictor of clinical outcome (Gray et al, 2001;Umekita et al, 2002). In cervical cancer, some preliminary work has detected micrometastases in histologically negative nodes (Van Trappen et al, 2001).…”