title: Prognostic Role of Adjuvant Chemotherapy in Node-Negative (N0), Triple-Negative (TN), Medullary Breast Cancer (MBC) in the Korean Population.
abstract: BACKGROUND
  Despite the favorable prognosis for medullary breast cancer (MBC), the guidelines for the use of adjuvant chemotherapy for MBC have not been clearly established. This study investigated the prognostic role of adjuvant chemotherapy in Korean patients with node-negative (N0), triple-negative (TN) MBC patients.
  
  
  METHODS
  We included data from 252 patients with N0 TN MBC, obtained from the Korean Breast Cancer Registry database. Patients were categorized as those who did not undergo adjuvant chemotherapy (group I) or those who did (group II). Clinicopathological characteristics, breast cancer-specific survival (BCSS), and overall survival (OS) were compared between the groups. In addition, a subgroup analysis for survival based on tumor size was conducted.
  
  
  RESULTS
  A total of 252 N0 TN MBC patients with tumor sizes >1 cm who were diagnosed between April 1997 and March 2011 were enrolled. The median age was 44.95 years (range, 25-72 years), and the median follow-up period was 93.94 months (range, 23-195 months). Overall, the BCSS and OS in group II (97.3% and 97.3%, respectively) were significantly better compared with those in group I (89.2% and 86.2%, respectively). In the subgroup analysis, in patients with tumors >2 cm in size, those in group II had significant better BCSS and OS (97.5% and 97.5%, respectively) compared with those in group I (78.3% and 73.9%, respectively). In contrast in those with tumors 1-2 cm in size, there were no significant differences in BCSS and OS between the groups (both 97.1% for group I, and 95.2% and 92.9%, respectively for group II). Multivariate analysis revealed that adjuvant chemotherapy significantly improved BCSS (P = 0.009) and OS (P = 0.007), but only for patients with larger tumors (>2 cm).
  
  
  CONCLUSIONS
  In patients with N0 TN MBC, adjuvant chemotherapy had a significant clinical survival benefit, but only in those with tumors >2 cm.
authors.affiliation: Division of Breast & Thyroid Surgical Oncology, Department of Surgery, College of Medicine, St. Vincent's Hospital, The Catholic University of Korea, Jungbu-daero 93, Paldal-gu, Suwon-si, Gyeonggi-do, 442-723, Republic of Korea.
authors.forename: SeungTaek
authors.initials: S
authors.lastname: Lim
authors.affiliation: Department of Surgery, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Republic of Korea.
authors.forename: Se Ho
authors.initials: SH
authors.lastname: Park
authors.affiliation: Breast Cancer Center, Department of Surgery, Gachon University Gill Hospital, 1198, Guwoldong, Incheon, 405-760, Republic of Korea.
authors.forename: Heong Kyu
authors.initials: HK
authors.lastname: Park
authors.affiliation: Department of Surgery, Cheil General Hospital and Women`s Healthcare Center, Dankook University College of Medicine, 17 Seoae-ro 1-gil, Jung-gu, Seoul, 100-380, Republic of Korea.
authors.forename: Min Hee
authors.initials: MH
authors.lastname: Hur
authors.affiliation: Department of Surgery, Incheon St. Mary`s Hospital, College of Medicine, The Catholic University of Korea, 56 Dongsu-ro, Bupyung-gu, Incheon, 403-720, Republic of Korea.
authors.forename: Se Jeong
authors.initials: SJ
authors.lastname: Oh
authors.affiliation: Division of Breast & Thyroid Surgical Oncology, Department of Surgery, College of Medicine, St. Vincent's Hospital, The Catholic University of Korea, Jungbu-daero 93, Paldal-gu, Suwon-si, Gyeonggi-do, 442-723, Republic of Korea.
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Suh
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D044466:Asian People; D018276:Carcinoma, Medullary / Q000188:drug therapy* / Q000208:ethnology / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008875:Middle Aged; D015999:Multivariate Analysis; D017063:Outcome Assessment, Health Care / Q000379:methods / Q000706:statistics & numerical data; D011379:Prognosis; D016016:Proportional Hazards Models; D056910:Republic of Korea; D064726:Triple Negative Breast Neoplasms / Q000188:drug therapy* / Q000208:ethnology / Q000473:pathology