title: BGX-Ki-67 index as a supplementary marker to MIB-1 index, enabling more precise distinction between luminal A and B subtypes of breast carcinoma and eliminating the problem of membranous/cytoplasmic MIB-1 staining.
abstract: OBJECTIVE
  We compared clinical utility of MIB-1 and BGX-Ki-67 clones of anti-Ki-67 antibody in a group of 156 patients with invasive ductal breast cancer.
  
  
  METHODS
  MIB-1 labeling index (MIB-1LI) and BGX labeling index (BGXLI) were evaluated immunohistochemically both in primary tumors (T) and synchronous lymph node metastasis (LNM).
  
  
  RESULTS
  In addition to nuclear MIB-1 staining, in 23 of 145 and 19 of 144 T and LNM, respectively, membranous/cytoplasmic labeling was found. In these cases, BGX-Ki-67 showed exclusively nuclear labeling and presented significantly higher labeling index. High BGXLI(T) was a significant independent negative prognostic factor for disease-free survival. Moreover, based on BGXLI(T)/BGXLI(LNM), patients with high MIB-1LI(T) were stratified into low- and high-risk carriers.
  
  
  CONCLUSIONS
  In carcinomas with membranous/cytoplasmic MIB-1 staining, additional assessment of BGXLI is recommended. It may help in defining breast cancer subtype and in selection of individuals at risk who, despite appropriate therapy, would benefit from more frequent controls aimed at earlier implementation of second-line treatment.
authors.affiliation: From the Departments of Applied Radiobiology, joanna@eikon.pl.
authors.forename: Joanna
authors.initials: J
authors.lastname: Niemiec
authors.affiliation: From the Departments of Applied Radiobiology.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Adamczyk
authors.affiliation: Tumor Pathology.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Ambicka
authors.affiliation: Head and Neck Cancers, and.
authors.forename: Anna
authors.initials: A
authors.lastname: Mucha-Małecka
authors.affiliation: Surgical Oncology, Maria Sklodowska-Curie Memorial Centre and Institute of Oncology, Krakow Branch, Krakow, Poland.
authors.forename: Wojciech M
authors.initials: WM
authors.lastname: Wysocki
authors.affiliation: From the Departments of Applied Radiobiology.
authors.forename: Kaja
authors.initials: K
authors.lastname: Majchrzyk
authors.affiliation: Tumor Pathology.
authors.forename: Janusz
authors.initials: J
authors.lastname: Ryś
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000401:mortality / Q000473:pathology*; D002462:Cell Membrane / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D013194:Staining and Labeling; D055815:Young Adult
chemical_list: D000906:Antibodies; D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen
keywords: BGXLI; Breast carcinoma; Lymph node metastases; MIB-1 LI; Prognostic significance