Surgical treatment of breast carcinoma after neoadjuvant therapy

Neoadjuvant therapy (NT) applied before breast cancer surgery can lead in favourable cases to regression of the tumor or its total disappearance - pathological complete response (pCR). Due to downstaging after NT, the extent of the surgery can be reduced. pCR represents an important prognostic factor for survival. The aim of this study was to evaluate the effectiveness of NT resulting in pCR on our sample of patients and to assess the frequency of locoregional recurrence (LRR) depending on the extent of the surgery in postoperative care.

This retrospective study was performed on a sample of 96 patients who underwent breast cancer surgery between 2006 and 2018 after previous NT. On the basis of the histological examination after surgery we evaluated the degree of regression and thus also pCR. In postoperative care we followed the patients for any occurrence of LRR in the breast and axilla.

pCR (Chevallier 1) was observed in 26 cases - 27.1%. During follow-up in postoperative care, 8 cases of LRR occurred - 8.3% (5.2% after mastectomy and 2.1% after breast-conserving surgery). Mean follow-up was almost 30 months with the median of 26.5 months.

With the development of new NT procedures a significant rise in pCR has occurred, predominantly in HER 2+ and triple negative subtypes, thus leading to a decreased incidence of LRR. The number of breast-conserving surgeries with sentinel lymph node biopsy is rising. In a select group of patients breast-conserving surgery is safe and is associated with a low number of LRR events.