PLoS ONE (Jan 2012)

Immunoglobulin kappa C predicts overall survival in node-negative breast cancer.

  • Zonglin Chen,
  • Aslihan Gerhold-Ay,
  • Susanne Gebhard,
  • Daniel Boehm,
  • Christine Solbach,
  • Antje Lebrecht,
  • Marco Battista,
  • Isabel Sicking,
  • Christina Cotarelo,
  • Cristina Cadenas,
  • Rosemarie Marchan,
  • Joanna D Stewart,
  • Mathias Gehrmann,
  • Heinz Koelbl,
  • Jan G Hengstler,
  • Marcus Schmidt

DOI
https://doi.org/10.1371/journal.pone.0044741
Journal volume & issue
Vol. 7, no. 9
p. e44741

Abstract

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BACKGROUND: Biomarkers of the immune system are currently not used as prognostic factors in breast cancer. We analyzed the association of the B cell/plasma cell marker immunoglobulin kappa C (IGKC) and survival of untreated node-negative breast cancer patients. MATERIAL AND METHODS: IGKC expression was evaluated by immunostaining in a cohort of 335 node-negative breast cancer patients with a median follow-up of 152 months. The prognostic significance of IGKC for disease-free survival (DFS) and breast cancer-specific overall survival (OS) was evaluated with Kaplan-Meier survival analysis as well as univariate and multivariate Cox analysis adjusted for age at diagnosis, pT stage, histological grade, estrogen receptor (ER) status, progesterone receptor (PR) status, Ki-67 and human epidermal growth factor receptor 2 (HER-2) status. RESULTS: 160 patients (47.7%) showed strong expression of IGKC. Univariate analysis showed that IGKC was significantly associated with DFS (P = 0.017, hazard ratio [HR] = 0.570, 95% confidence interval [CI] = 0.360-0.903) and OS (P = 0.011, HR = 0.438, 95% CI = 0.233-0.822) in the entire cohort. The significance of IGKC was especially strong in ER negative and in luminal B carcinomas. In multivariate analysis IGKC retained its significance independent of established clinical factors for DFS (P = 0.004, HR = 0.504, 95% CI = 0.315-0.804) as well as for OS (P = 0.002, HR = 0.371, 95% CI = 0.196-0.705). CONCLUSION: Expression of IGKC has an independent protective impact on DFS and OS in node-negative breast cancer.