title: Tailoring treatment for ductal intraepithelial neoplasia of the breast according to Ki-67 and molecular phenotype.
abstract: BACKGROUND
  The post-surgical management of ductal intraepithelial neoplasia (DIN) of the breast is still a dilemma. Ki-67 labelling index (LI) has been proposed as an independent predictive and prognostic factor in early breast cancer.
  
  
  METHODS
  The prognostic and predictive roles of Ki-67 LI were evaluated with a multivariable Cox regression model in a cohort of 1171 consecutive patients operated for DIN in a single institution from 1997 to 2007.
  
  
  RESULTS
  Radiotherapy (RT) was protective in subjects with DIN with Ki-67 LI ≥ 14%, whereas no evidence of benefit was seen for Ki-67 LI <14%, irrespective of nuclear grade and presence of necrosis. Notably, the higher the Ki-67 LI, the stronger the effect of RT (P-interaction <0.01). Hormonal therapy (HT) was effective in both Luminal A (adjusted hazard ratio (HR)=0.56 (95% CI, 0.33-0.97)) and Luminal B/Her2neg DIN (HR 0.51 (95% CI, 0.27-0.95)).
  
  
  CONCLUSIONS
  Our data suggest that Ki-67 LI may be a useful prognostic and predictive adjunct in DIN patients. The Ki-67 LI of 14% could be a potential cutoff for better categorising this population of women at increased risk for breast cancer and in which adjuvant treatment (RT, HT) should be differently addressed, independent of histological grade and presence of necrosis.
authors.affiliation: Division of Cancer Prevention and Genetics, European Institute of Oncology, Milan, Italy. matteo.lazzeroni@ieo.it
authors.forename: M
authors.initials: M
authors.lastname: Lazzeroni
authors.forename: A
authors.initials: A
authors.lastname: Guerrieri-Gonzaga
authors.forename: E
authors.initials: E
authors.lastname: Botteri
authors.forename: M C
authors.initials: MC
authors.lastname: Leonardi
authors.forename: N
authors.initials: N
authors.lastname: Rotmensz
authors.forename: D
authors.initials: D
authors.lastname: Serrano
authors.forename: C
authors.initials: C
authors.lastname: Varricchio
authors.forename: D
authors.initials: D
authors.lastname: Disalvatore
authors.forename: A
authors.initials: A
authors.lastname: Del Castillo
authors.forename: F
authors.initials: F
authors.lastname: Bassi
authors.forename: G
authors.initials: G
authors.lastname: Pagani
authors.forename: A
authors.initials: A
authors.lastname: DeCensi
authors.forename: G
authors.initials: G
authors.lastname: Viale
authors.forename: B
authors.initials: B
authors.lastname: Bonanni
authors.forename: G
authors.initials: G
authors.lastname: Pruneri
mesh_terms: D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage; D001943:Breast Neoplasms / Q000378:metabolism / Q000532:radiotherapy / Q000601:surgery / Q000628:therapy*; D002278:Carcinoma in Situ / Q000378:metabolism / Q000532:radiotherapy / Q000601:surgery / Q000628:therapy*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000532:radiotherapy / Q000601:surgery / Q000628:therapy*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000378:metabolism / Q000532:radiotherapy / Q000601:surgery / Q000628:therapy*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008875:Middle Aged; D010641:Phenotype; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D013629:Tamoxifen / Q000008:administration & dosage
chemical_list: D018931:Antineoplastic Agents, Hormonal; D019394:Ki-67 Antigen; D013629:Tamoxifen