In vivo detection of circulating tumour cell clusters by photodiagnostic spectroscopy

BACKGROUND: We demonstrate a new diagnostic method, Photodiagnostic Infrared Spectroscoppy (PDIS), which is able to detect circulating tumor clusters and circulating tumor cells in the circulatory system. METHODS: The PDIS method is based on photodiagnostic physics and high resolution spectroscopy and is using calibrated spectroscopic data for the diagnostic analysis of the blood screening spectra. Using Confocal Laser Scanning Mikcroscopy the Indocyangreen-uptake of different cell lines of breast cancer cells is studied. RESULTS: The PDIS supplies calibrated diagnostic data about the presence or absence of CTCs and CTC clusters in the bloodstream with a sensitivity of 98 %. Therefore, the PDIS is suited to control the blood of cancer patients with respect of CTC and CTC clusters with an resolution of one CTC and one CTC cluster per blood volume. PDIS distinguishes the different phenotypes of CTC clusters. CONCLUSION: Circulating tumor cell slusters play a key role in the metastatic process and are formed only in solid tumors, they are appropriate objects to validate cancer treatments and to recognice cancer formation. The PDIS is a calibrated diagnostic method which allows to evaluate the results of solid tumor treatments and of chemotherapy treatments and to optimize the individual cancer treatment strategies.