Neurotrophic receptor, tropomyosin-related kinase B as an independent prognostic marker in gastric cancer patients.

Background and Objectives: Neurotrophic receptor tyrosine kinase TrkB has been associated with clinical outcome and chemotherapy resistance in neuroblastoma and certain human malignancies. Recent studies have focused on the association between metastatic potential and TrkB expression in tumor cells.
Methods: To determine the role of TrkB in gastric cancer, we analyzed TrkB mRNA levels by real-time reverse transcription polymerase chain reaction in 90 patients with gastric cancer. TrkB levels were correlated with clinicopathological variables. The association between TrkB and overall survival was evaluated by univariate and multivariate analyses.
Results: The mean TrkB level in gastric cancer tissue was 2.96 (range, 0-27.1). Thirty-eight (42%) of 90 patients showed detectable TrkB levels, whereas the remainder had no detectable TrkB. There was no significant association between clinicopathological variables and TrkB positivity. TrkB level was significantly associated with extent of lymph node metastasis in node positive patients (P = 0.03). TrkB positivity (n = 38) was significantly correlated with worse patient survival (P = 0.03). Multivariate analysis showed TrkB to be an independent prognostic parameter for overall survival (P = 0.04).
Conclusions: TrkB is an independent prognostic marker in patients with gastric cancer and appears to be associated with metastatic potential.