Development of a molecular multimarker assay for the analysis of circulating tumor cells in adenocarcinoma patients.

BACKGROUND

The analysis of circulating tumor cells (CTCs) is emerging as a promising diagnostic tool in oncology. However, even if a variety of methods for CTC isolation have been already developed, their specificity and/or sensitivity still remain problematic. The aim of this study was to develop an immunomagnetic/real-time reverse transcription polymerase chain reaction (RT-PCR) assay for the molecular detection of circulating tumor cells (CTCs) in peripheral blood (PB) of adenocarcinoma cancer patients.

METHODS

The presence of CTCs was evaluated in 945 PB blood samples from 247 adenocarcinoma cancer patients and in 42 healthy controls by immunomagnetic enrichment using the antibodies BM7 and VU1D9 followed by real-time RT-PCR analysis of the marker genes KRT19, MUC1, EPCAM, CEACAM5, BIRCS, SCGB2A2, and ERBB2.

RESULTS

The developed assay showed not only high specificity, as none of the healthy controls were found positive for the multimarker gene panel, but also great sensitivity as CTCs were detected in adenocarcinomas arising from 10 different organs. According to tumor primary origin, CTC positivity was detected in 33.3% of Ampulla of Vater adenocarcinomas, 69.6% of bile ducts adenocarcinomas, 61.3% of breast adenocarcinomas, 61.3% of cardia adenocarcinomas, 60.6% of colon adenocarcinomas, 66.7% of esophagus adenocarcinomas, 57.1% of pancreas adenocarcinomas, 66.7% of rectum adenocarcinomas, 33.3% of small intestine adenocarcinomas, and 62.2% of stomach adenocarcinomas.

CONCLUSIONS

Our results suggest that the current developed technique can be used to detect CTCs in all major adenocarcinomas, with great sensitivity without compromising specificity.