What Is the Best Management of cN0pN1(sn) Breast Cancer Patients?

Abstract

Although the majority of breast cancer patients are clinically node-negative (cN0) at diagnosis, 15-20% will have a metastatic sentinel lymph node (SLN, pN1(sn)). While a less radical approach regarding axillary surgery in cN0 patients with a positive SLN biopsy is advocated, the limitations of 5 published trials on axillary management in pN1(sn) are discussed intensely in the literature and support the performance of ongoing validation and extension trials, especially considering the lack of data in the setting of mastectomy. As locoregional radiotherapy has a significant effect on both recurrence and survival, a standardization of locoregional radiotherapy in the situation of SLN biopsy alone in pN1(sn) patients has to be defined in the future, and de-escalation trials should embrace a truly multidisciplinary approach. This is also of utmost importance considering the fact that high-volume nodal disease requires an intensified adjuvant chemotherapy strategy to which patients omitting axillary dissection cannot be stratified. Finally, there is mounting evidence that the therapeutic role of extensive axillary surgery in low-volume nodal disease is negligible, and multidisciplinary and translational efforts must be undertaken to individualize treatment in order to gain a reasonable balance between necessary staging information and unnecessary treatment-related morbidity.

Keywords: Axillary surgery; Breast cancer; Radiotherapy; Sentinel lymph node biopsy.

Fig. 1

Relative survival (≈ tumor-specific survival) by number of positive lymph nodes based on data from the Munich Cancer Registry (MCR) (M0 at diagnosis, without neoadjuvant therapy).

Fig. 2

Relative survival (≈ tumor-specific survival) by intrinsic (-like) subtype for patients with 1–3 positive lymph nodes based on data from the Munich Cancer Registry (MCR) (M0 at diagnosis, without neoadjuvant therapy).