Exploiting LIBS as a spectrochemical analytical technique in diagnosis of some types of human malignancies

In the present work we are presenting a detailed in vitro study of using laser-induced breakdown spectroscopy (LIBS) as a quick and simple method for spectrochemical analysis to identify and characterize some types of human malignancies. This has been performed via detection of the abundance of certain elements namely calcium and magnesium in malignant tissues with respect to the non-neoplastic ones. In order to improve the performance of the LIBS technique - in particular its sensitivity, reproducibility and limit of detection - the measurements have been performed under vacuum (10(-2) Torr) and the samples were frozen down to -196 degrees C in a specially designed vacuum chamber. Under such experimental arrangements a pronounced enhancement has been achieved in the signal to noise (S/N) ratio of different spectral lines. Significant discriminating results have been obtained in case of breast and colorectal cancers indicating the possibility of adopting LIBS in the early detection of the malignancy as well as the identification of the severity and the grade of the disease. The present work demonstrated that future in vivo measurements are also feasible and reliable using especial endoscopic systems for delivery of laser beam and collection of the emitted plasma light.