Clinical outcome with correlation to disseminated tumor cell (DTC) status after DTC-guided secondary adjuvant treatment with docetaxel in early breast cancer

J Clin Oncol. 2014 Dec 1;32(34):3848-57. doi: 10.1200/JCO.2014.56.9327. Epub 2014 Nov 3.

Abstract

Purpose: The presence of disseminated tumor cells (DTCs) in bone marrow (BM) predicts survival in early breast cancer. This study explores the use of DTCs for identification of patients insufficiently treated with adjuvant therapy so they can be offered secondary adjuvant treatment and the subsequent surrogate marker potential of DTCs for outcome determination.

Patients and methods: Patients with early breast cancer who had completed six cycles of adjuvant fluorouracil, epirubicin, and cyclophosphamide (FEC) chemotherapy underwent BM aspiration 2 to 3 months (BM1) and 8 to 9 months (BM2) after FEC. Presence of DTCs in BM was determined by immunocytochemistry using pan-cytokeratin monoclonal antibodies. If one or more DTCs were present at BM2, six cycles of docetaxel (100 mg/m(2), once every 3 weeks) were administered, followed by DTC analysis 1 and 13 months after the last docetaxel infusion (after treatment). Cox regression analysis was used to evaluate disease-free interval (DFI).

Results: Of 1,066 patients with a DTC result at BM2 and available follow-up information (median follow-up, 71.9 months from the time of BM2), 7.2% were DTC positive. Of 72 docetaxel-treated patients analyzed for DTCs after treatment, 15 (20.8%) had persistent DTCs. Patients with remaining DTCs had markedly reduced DFI (46.7% experienced relapse) compared with patients with no DTCs after treatment (adjusted hazard ratio, 7.58; 95% CI, 2.3 to 24.7). The docetaxel-treated patients with no DTCs after treatment had comparable DFI (8.8% experienced relapse) compared with those with no DTCs both at BM1 and BM2 (12.7% experienced relapse; P = .377, log-rank test).

Conclusion: DTC status identifies high-risk patients after FEC chemotherapy, and DTC monitoring status after secondary treatment with docetaxel correlated strongly with survival. This emphasizes the potential for DTC analysis as a surrogate marker for adjuvant treatment effect in breast cancer.

Trial registration: ClinicalTrials.gov NCT00248703.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't
  • Webcast

MeSH terms

  • Antineoplastic Agents, Phytogenic / administration & dosage*
  • Antineoplastic Agents, Phytogenic / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Bone Marrow Cells / chemistry
  • Bone Marrow Cells / drug effects*
  • Bone Marrow Cells / pathology
  • Breast Neoplasms / chemistry
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / mortality
  • Breast Neoplasms / pathology
  • Chemotherapy, Adjuvant
  • Chi-Square Distribution
  • Cyclophosphamide / administration & dosage
  • Disease-Free Survival
  • Docetaxel
  • Drug Administration Schedule
  • Epirubicin / administration & dosage
  • Female
  • Fluorouracil / administration & dosage
  • Humans
  • Immunohistochemistry
  • Infusions, Intravenous
  • Kaplan-Meier Estimate
  • Keratins / analysis
  • Ki-67 Antigen / analysis
  • Middle Aged
  • Neoplastic Cells, Circulating / chemistry
  • Neoplastic Cells, Circulating / drug effects*
  • Neoplastic Cells, Circulating / pathology
  • Norway
  • Predictive Value of Tests
  • Proportional Hazards Models
  • Prospective Studies
  • Retreatment
  • Risk Factors
  • Taxoids / administration & dosage*
  • Taxoids / adverse effects
  • Time Factors
  • Treatment Failure

Substances

  • Antineoplastic Agents, Phytogenic
  • Ki-67 Antigen
  • Taxoids
  • Docetaxel
  • Epirubicin
  • Keratins
  • Cyclophosphamide
  • Fluorouracil

Supplementary concepts

  • FEC protocol

Associated data

  • ClinicalTrials.gov/NCT00248703