Neoadjuvant chemotherapy in breast cancer significantly reduces number of yielded lymph nodes by axillary dissection

Abstract

BackgroundNeoadjuvant chemotherapy (NC) is an established therapy in breast cancer, able to downstage positive axillary lymph nodes, but might hamper their detectibility. Even if clinical observations suggest lower lymph node yield (LNY) after NC, data are inconclusive and it is unclear whether NC dependent parameters influence detection rates by axillary lymph node dissection (ALND).MethodsWe analyzed retrospectively the LNY in 182 patients with ALND after NC and 351 patients with primary ALND. Impact of surgery or pathological examination and specific histomorphological alterations were evaluated. Outcome analyses regarding recurrence rates, disease free (DFS) and overall survival (OS) were performed.ResultsAxillary LNY was significantly lower in the NC in comparison to the primary surgery group (median 13 vs. 16; p < 0.0001). The likelihood of incomplete axillary staging was four times higher in the NC group (14.8% vs. 3.4%, p < 0.0001). Multivariate analyses excluded any influence by surgeon or pathologist. However, the chemotherapy dependent histological feature lymphoid depletion was an independent predictive factor for a lower LNY. Outcome analyses revealed no significant impact of the LNY on local and regional recurrence rates as well as DFS and OS, respectively.ConclusionNC significantly reduces the LNY by ALND and has profound effects on the histomorphological appearance of lymph nodes. The current recommendations for a minimum removal of 10 lymph nodes by ALND are clearly compromised by the clinically already established concept of NC. The LNY of less than 10 by ALND after NC might not be indicative for an insufficient axillary staging.

A new era of neoadjuvant treatment with Pertuzumab: Should the 10‐lymph node guideline for axillary lymph node dissection in breast cancer be revised?

“…Whether or not an adequate dissection as described by current guidelines is relevant to patients who received neoadjuvant therapy has been an ongoing source of contention. Our finding of less than 10 lymph axillary lymph nodes recovered following neoadjuvant chemotherapy is validated in other studies . However, other studies have observed no effect of neoadjuvant therapy on the number of axillary lymph nodes recovered .…”

“…Improved disease‐free survival has been observed in patients with at least 10 axillary nodes recovered in the ALND specimen, and thus, this number has become the foundation of the practice‐based guidelines of the American Society of Breast Surgeons . However, neoadjuvant therapies, specifically those targeting human epidermal growth factor receptor 2 (HER2) positive breast cancer, have resulted in improved pathologic complete response (pCR) and, at times, obliteration of axillary lymph nodes …”

Prognostic Value of Axillary Nodal Ratio after Neoadjuvant Chemotherapy of Doxorubicin/Cyclophosphamide Followed by Docetaxel in Breast Cancer: A Multicenter Retrospective Cohort Study

“…It should be noted that the number of retrieved and examined LNs is influenced by NCT [9,10]. In our study, most patients (92.8%) completed the preplanned eight cycles of NCT, while only three cycles of NCT were utilized in previous studies [17,18].…”

“…However, based on previous observations, NCT may change the histological environment of the axillary area and reduce the number of retrieved axillary LNs [9,10]. As a result, the ypN stage can be underestimated, thereby resulting in inadequate treatment.…”

Preoperative Fine Needle Aspiration of Axillary Lymph Nodes in Breast Cancer: Clinical Utility, Diagnostic Accuracy and Potential Pitfalls

“…Brown et al [10] described similar changes in sentinel lymph nodes with a treatment effect. Erbes et al [11] demonstrated the importance of identifying postchemotherapy fibrosis and lymphocyte depletion in lymph nodes. These false positive cases were in fact not true ‘false positive' cases, as axillary lymph node FNA was performed preoperatively and follow-up histology was performed following neoadjuvant chemotherapy.…”