Clinical evidence of breast cancer micrometastasis in the era of sentinel node biopsy

Abstract

Sentinel node biopsy for early-stage breast cancer has been established as an excellent surgical and staging procedure developed to enhance the detection of minimal lymph node involvement such as micrometastases. Multisection and the proper use of immunohistochemical staining have led to the increased detection of micrometastases, and this has given rise to new questions about the treatment to be employed concerning micrometastasis. That is whether complete axillary lymph node dissection (ALND) and adjuvant systemic therapy are really required for patients with micrometastasis because of the low prevalence of nonsentinel lymph node metastasis. Some currently published case studies report that selected patients with micrometastases without further ALND would not suffer from a high incidence of regional recurrence. However, the long-term prognostic risk of systemic recurrence and local failure associated with residual axillary disease in the sentinel lymph node-positive patient electing for no further axillary surgery has not been defined. Numerous studies have investigated the impact of occult metastases, which may be regarded as micrometastases or a small tumor deposit. Although data from randomized controlled trials are lacking, these studies suggest that the prognosis of breast cancer patients with micrometastases should not be considered the same as that in truly node-negative patients. Patients with micrometastases should have some adjuvant systemic therapy. Ongoing randomized trials will provide prospective answers to the question of the optimal treatment for micrometastasis.

Sentinel Lymph Node Biopsy in Breast Cancer: Predictors of Axillary and Non-Sentinel Lymph Node Involvement

“…Some authors recommended complementary axillary dissection in patients with micrometastasis due to the relationship of subclinical nodal disease with worse survival figures (3,(5)(6)(7)25).…”

“…Recent data from studies investigating the prognostic significance of lymph node micrometastases compared with node-negative disease revealed poorer disease-free survival (DFS) (3), which was close to 40% (4), or overall survival (OS) rates in the micrometastatic group (5,6). Thus, the data emphasised the risk of observational protocols in this subgroup of patients (7). On the contrary, a novel conservative approach omitting ALND in SLN-positive patients has been suggested recently (8).…”

Histopathologic Characteristics of Sentinel Lymph Node Biopsy in Breast Carcinoma: Uludağ University Faculty of Medicine Experience

“…Di a me ter of the tumor, lympha tic in va si on and pe ri ne u ral in va si on de ter mi ne n-SLN me tas ta sis and as a con se qu en ce they de ter mi ne axil lary dis sec ti on. 12,23,24 The ra te of po si ti ve SLN varies bet we en 27-45%. In our se ri es, the po si ti ve SLN was 33.4%.…”

Comparison of Immunohistochemistry with Conventional Histopathology for Evaluation of Sentinel Lymph Node in Breast Cancer

“…However it may show a false negative result in patients with poorly differentiated breast cancer as happened in 2 of our patients (6% false negative rate). There is also concern that routine use of IHC may increase the detection of false positive tumor deposits and the detection of micrometastasis of no biological relevance [12].…”