title: Neoadjuvant chemotherapy in breast-conserving surgery - Consequences on margin status and excision volumes: A nationwide pathology study.
abstract: Neoadjuvant chemotherapy (NACT) is increasingly used in patients with operable disease due to the potential of converting patients requiring mastectomy to breast conserving surgery (BCS) or lowering resection volumes to improve cosmetic outcome. This nationwide retrospective study aims to determine margin status and specimen volume in patients with invasive breast cancer who underwent BCS after NACT.
  
  
  
  All patients who underwent BCS in 2012-2013 for invasive breast cancer were selected from a nationwide network and registry of histology and cytopathology in the Netherlands (PALGA).
  
  
  
  Of the 9901 patients, 626 (6.3%) received NACT. After primary surgery 949 (10.2%) patients had tumour-involved margins compared to 152 (24.3%) after NACT. Close margins (≤1 mm) were seen in another 111 (17.7%) patients after NACT. The adjusted odds ratio for involved margins after NACT was 2.94, meaning a three times higher risk of involved margins compared with primary surgery. In patients with lobular carcinoma (54.9%) and no response to NACT (42.1%) higher tumour-involved margins were seen. High resection volumes >60 cc were observed in 224 (36%) patients after NACT of which 37 (16.5%) had tumour involved margins and 32 (14.3%) close margins ≤1 mm.
  
  
  
  The primary goal of the surgeon performing BCS after NACT, to reach tumour-free margins, is not accomplished in one out of four patients. Patients especially at risk are patients with ILC and no pathological tumour response. Excessive resection volumes after NACT do not guarantee tumour-free margins. Further research is necessary to analyze whether we are counterproductive when NACT is given in order to lower resection volumes.
authors.affiliation: Department of Surgical Oncology, Gelderse Vallei Hospital, Ede, The Netherlands. Electronic address: Mp.vandentol@vumc.nl.
authors.forename: J H
authors.initials: JH
authors.lastname: Volders
authors.affiliation: Department of Surgical Oncology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: M H
authors.initials: MH
authors.lastname: Haloua
authors.affiliation: Department of Plastic Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: N M A
authors.initials: NM
authors.lastname: Krekel
authors.affiliation: Department of Surgical Oncology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: V L
authors.initials: VL
authors.lastname: Negenborn
authors.affiliation: Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Barbé
authors.affiliation: Department of Surgical Oncology, Gelderse Vallei Hospital, Ede, The Netherlands.
authors.forename: C
authors.initials: C
authors.lastname: Sietses
authors.affiliation: Department of Epidemiology and Biostatistics, NKI-AVL, Amsterdam, The Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: Jóźwiak
authors.affiliation: Department of Surgical Oncology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: Meijer
authors.affiliation: Department of Surgical Oncology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: M P
authors.initials: MP
authors.lastname: van den Tol
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000473:pathology; D018275:Carcinoma, Lobular / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D000072662:Margins of Excision; D015412:Mastectomy, Segmental; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods*; D018365:Neoplasm, Residual / Q000188:drug therapy / Q000473:pathology; D009426:Netherlands; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Breast cancer; Breast conserving therapy; Margins; Neoadjuvant chemotherapy; Volume