Leveraging the increased rates of pathologic complete response after neoadjuvant treatment in breast cancer to de-escalate surgical treatments

J Surg Oncol. 2021 Jan;123(1):71-79. doi: 10.1002/jso.26236. Epub 2020 Oct 1.

Abstract

Introduction: Breast conservative surgery (BCS) and sentinel lymph node biopsy (SLNB) after neoadjuvant treatment (NAT) is safe and effective for selected patients. This aim of this study is to evaluate the impact of anatomic site of response on outcomes and to assess the real population who may benefit from nonsurgical approaches after NAT.

Material and methods: From a prospectively maintained database, patients with T1-4 N0-2 breast cancer undergoing NAT were identified. Clinicopathological and survival rates were compared in relation to response and anatomic site of response.

Results: Six hundred and forty-six patients were included in the study. Pathologic complete response (pCR) was an independent factor for BCS and SLN. HER2 positive and TN tumors with cN0 achieving a breast pCR remain ypN0 (p = .002). Residual axillary disease was associated with breast residual tumor (p = .05) and subtype (p = .001). With a median follow up of 35.25 months, patients with any pCR had improved survival when compared with partial response, but not significant differences between pCR, axillary pCR, or breast pCR.

Conclusion: Achieving a pCR increases BCS and SLN. In selected subgroups, sparing any axillary surgery after NAT maybe feasible. In cN+ patients, any pCR was associated with survival, but not the anatomic site of response.

Keywords: breast neoplasms; de-escalation; neoadjuvant therapy; pathologic complete response; survival.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Breast Neoplasms / drug therapy
  • Breast Neoplasms / pathology*
  • Breast Neoplasms / surgery
  • Carcinoma, Ductal, Breast / drug therapy
  • Carcinoma, Ductal, Breast / secondary*
  • Carcinoma, Ductal, Breast / surgery
  • Carcinoma, Lobular / drug therapy
  • Carcinoma, Lobular / secondary*
  • Carcinoma, Lobular / surgery
  • Combined Modality Therapy
  • Female
  • Follow-Up Studies
  • Humans
  • Lymphatic Metastasis
  • Mastectomy / mortality*
  • Middle Aged
  • Neoadjuvant Therapy / mortality*
  • Neoplasm Invasiveness
  • Neoplasm Recurrence, Local / drug therapy
  • Neoplasm Recurrence, Local / pathology*
  • Neoplasm Recurrence, Local / surgery
  • Prognosis
  • Prospective Studies
  • Sentinel Lymph Node Biopsy
  • Survival Rate
  • Young Adult