Current practice guidelines recommend the combination of
chemotherapy and thoracic radiation for locally advanced
non-small cell lung cancer (NSCLC). Previous meta-analyses have shown that concurrent chemoradiation (CCRT) may be superior to sequential chemoradiation (SCRT). However, few previous in vitro studies have analyzed these two treatment schedules. In the current study, four
lung cancer cell lines harboring wild-type
epidermal growth factor receptor, comprising two squamous and two non-squamous cell lines, were used. The IC10 concentrations of three
platinum-based regimens were combined with
radiation treatment. Cells were irradiated at 0, 2, 4, 6 and 8 Gy using a 137Cs irradiator concurrently or sequentially. Surviving fractions (SFs) were plotted as a function of the radiation dose. In A549 cells, only the
docetaxel (Doc) and
carboplatin (Carbo) combination showed a significant
radiosensitizing effect with CCRT treatment. For the other three cell lines, no difference was identified in the SFs between CCRT and SCRT. An in vitro method of comparing CCRT with SCRT was established using
lung cancer cell lines. Overall, no significant difference was detected in the
radiosensitizing effect of the two treatment schedules, with the exception of the A549 cell lines treated with Doc/Carbo.