title: Phase III, multicenter, randomized trial of maintenance chemotherapy versus observation in patients with metastatic breast cancer after achieving disease control with six cycles of gemcitabine plus paclitaxel as first-line chemotherapy: KCSG-BR07-02.
abstract: OBJECTIVE
  The primary purpose of our study was to evaluate whether maintenance chemotherapy with paclitaxel/gemcitabine (PG) was superior to observation in improving progression-free survival (PFS) in patients with metastatic breast cancer (MBC) who achieved disease control with an initial six cycles of PG as their first-line treatment.
  
  
  METHODS
  The study was a prospective, randomized, multicenter, phase III trial. Patients MBC with who achieved disease control after six cycles of PG chemotherapy were randomly assigned to maintenance chemotherapy or observation until progression.
  
  
  RESULTS
  Of 324 patients from 10 centers enrolled, 231 patients with MBC exhibited disease control (complete response + partial response + stable disease) with first-line PG and were randomly assigned to maintenance chemotherapy (n = 116) or observation (n = 115). The median age was 48 years (range, 28 to 76 years), median follow-up was 33 months, and median number of chemotherapy cycles in the maintenance group after random assignment was six. The median PFS time after random assignment was longer in the maintenance group than in the observation group (7.5 v 3.8 months, respectively; P = .026). The median overall survival (OS) time was longer in the maintenance group than in the observation group (32.3 v 23.5 months, respectively; P = .047). The rate of grade 3 or higher neutropenia after random assignment was higher in the maintenance group than in the observation group (61% v 0.9%, respectively; P < .001).
  
  
  CONCLUSIONS
  In patients with MBC who achieved disease control with an initial six cycles of PG chemotherapy, maintenance PG chemotherapy resulted in better PFS and OS compared with observation.
authors.affiliation: Division of Hematology/Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong Gangnam-gu, Seoul, Korea.
authors.forename: Yeon Hee
authors.initials: YH
authors.lastname: Park
authors.forename: Kyung Hae
authors.initials: KH
authors.lastname: Jung
authors.forename: Seock-Ah
authors.initials: SA
authors.lastname: Im
authors.forename: Joo Hyuk
authors.initials: JH
authors.lastname: Sohn
authors.forename: Jungsil
authors.initials: J
authors.lastname: Ro
authors.forename: Jin-Hee
authors.initials: JH
authors.lastname: Ahn
authors.forename: Sung-Bae
authors.initials: SB
authors.lastname: Kim
authors.forename: Byung-Ho
authors.initials: BH
authors.lastname: Nam
authors.forename: Do Youn
authors.initials: DY
authors.lastname: Oh
authors.forename: Sae-Won
authors.initials: SW
authors.lastname: Han
authors.forename: Soohyeon
authors.initials: S
authors.lastname: Lee
authors.forename: In Hae
authors.initials: IH
authors.lastname: Park
authors.forename: Keun Seok
authors.initials: KS
authors.lastname: Lee
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Seok Yun
authors.initials: SY
authors.lastname: Kang
authors.forename: Moon Hee
authors.initials: MH
authors.lastname: Lee
authors.forename: Hee Sook
authors.initials: HS
authors.lastname: Park
authors.forename: Jin Seok
authors.initials: JS
authors.lastname: Ahn
authors.forename: Young-Hyuck
authors.initials: YH
authors.lastname: Im
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology*; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D018572:Disease-Free Survival; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D060046:Maintenance Chemotherapy / Q000379:methods; D008875:Middle Aged; D009367:Neoplasm Staging; D017239:Paclitaxel / Q000008:administration & dosage; D011446:Prospective Studies; D056910:Republic of Korea; D016896:Treatment Outcome; D057832:Watchful Waiting; D000093542:Gemcitabine
chemical_list: D003841:Deoxycytidine; D017239:Paclitaxel; D000093542:Gemcitabine