Background: Fluorometric microculture cytotoxicity assay (FMCA) is a short-term semi-automatic method, based on dye-inclusion of surviving cells. The assay was developed for investigations of drug resistance on tumour cells from biopsy material. In the present study, this short-term assay was evaluated, regarding usefulness in determining radio-sensitivity.
Materials and methods: Eight human lung cancer cell lines were used. There were five small cell lung cancer (SCLC and three non-small cell lung cancer (NSCLC cell lines. Results were compared with the corresponding data derived from the clonogenic assay and/or the extrapolation method.
Results: The surviving fraction (SF) after 2, 5 and 10 Gy compared with data from the clonogenic assay were not in accordance for 5 of the 8 cell lines. The FMCA assay overestimated SF- values for the SCLC cell lines.
Conclusion: The FMCA assay is not useful as a quick screening method for the radioresponsiveness in vitro of human tumour cell lines.