Postoperative detection of circulating EGFR transcripts as a surrogate marker for circulating tumor cells to predict tumor recurrence after adjuvant radio(chemo)therapy in locally advanced squamous cell carcinoma of the head and neck (LASCCHN)
You can manage bookmarks using lists, please log in to your user account for this.
Media type:
E-Article
Title:
Postoperative detection of circulating EGFR transcripts as a surrogate marker for circulating tumor cells to predict tumor recurrence after adjuvant radio(chemo)therapy in locally advanced squamous cell carcinoma of the head and neck (LASCCHN)
Description:
6014 Background: The prognostic role of circulating tumor cells (CTCs), occurring in up to 35% of LASCCHN patients, is still largely undetermined. In this prospective study we tested whether the detection of CTCs was associated with treatment outcome of adjuvant radio(chemo)therapy. Methods: Patients with LASCCHN (N=64) of the oropharynx (N=40), oral cavity (N=15), hypopharynx (N=3) or CUP (N=6) presenting after tumor surgery for adjuvant treatment were enrolled in this study. Peripheral blood samples were collected before start and at the end of adjuvant radio- (N=22) or radiochemotherapy (N=42). Transcripts of epidermal growth factor receptor (EGFR) were detected using RT-PCR. Samples positive in at least 2 of 3 PCR replicates were considered CTC-positive, according to previous studies. CTC detection was correlated with failure-free (FFS) and overall survival (OS). Results: CTCs were detected in blood samples from 21 of 64 patients (33%) whereas all 30 samples from healthy donors used as control were negative. The CTC+ and CTC- patient cohorts were comparable with relation to sex, age, smoking history, T and N stage, tumor localization, type of adjuvant treatment and the median follow-up for OS and FFS. Detection of CTCs before or after adjuvant treatment was not predictive for OS. However, the presence of CTCs at the start of adjuvant radio(chemo)therapy identified patients with reduced FFS (CTC- vs CTC+ [% of patients without relapse at 2 years]: 89% vs. 60%, HR: 0.30, 95% CI: .08-.92, p=.037). Multivariate Cox regression analysis revealed that the prognostic value of the CTC status was not influenced by the T and N stage and independent of whether the adjuvant treatment consisted of radio- or radiochemotherapy. Conclusions: Persistence of CTCs after tumor resection as detected by EGFR transcripts was established as an independent marker for tumor recurrence in LASCCHN. Postoperative detection of CTCs might prove useful for risk stratification in future clinical trials for optimization of adjuvant treatment, especially for the poor-prognosis group of CTC+ patients.