title: Significance of serum carcinoembryonic antigen and CA 15-3 in monitoring advanced breast cancer patients treated with systemic therapy: a large-scale retrospective study.
abstract: OBJECTIVE
  The significance of serum carcinoembryonic antigen (CEA) and CA 15-3 in monitoring advanced breast cancer is still controversial. To clarify this issue, the Tumor Marker Study Group of the Japanese Breast Cancer Society conducted a large-scaled retrospective study.
  
  
  METHODS
  The findings from four clinical trials and seven institutes of 528 patients with advanced breast cancer were collected. Three-hundred forty-eight patients, in whom both serum CEA and CA 15-3 were measured during therapy, were selected for analysis.
  
  
  RESULTS
  The pretreatment positivity rate of CA 15-3 was significantly higher than that of CEA (p<0.0001). Time-to-progression (TTP) in CEA- and CA 15-3-positive patients was significantly shorter than TTP in negative patients. The changes in either marker level correlated well with response to therapy in marker-positive patients but not in negative patients. TTP in the marker-positive patients with a greater than 20%-reduction in either marker level during therapy was significantly longer than that in positive patients without such a reduction (p<0.01 for CEA and CA 15-3).
  
  
  CONCLUSIONS
  CA 15-3 is more useful for monitoring advanced breast cancer than CEA and a greater than 20%-reduction in marker levels suggests longer TTP in pretreatment marker-positive patients.
authors.affiliation: Department of Breast and Thyroid Surgery, Kawasaki Medical School, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Kurebayashi
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Tanaka
authors.forename: Norio
authors.initials: N
authors.lastname: Kohno
authors.forename: Masafumi
authors.initials: M
authors.lastname: Kurosumi
authors.forename: Takuya
authors.initials: T
authors.lastname: Moriya
authors.forename: Reiki
authors.initials: R
authors.lastname: Nishimura
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Taguchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000097:blood* / Q000188:drug therapy; D002272:Carcinoembryonic Antigen / Q000097:blood*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008875:Middle Aged; D018396:Mucin-1 / Q000097:blood*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D018396:Mucin-1