Identification of mRNA markers for molecular staging of lymph nodes in colorectal cancer

Background: One evolving approach to improved prognostication of cancer patients is the identification of previously occult disease by use of quantitative reverse transcription-PCR. Surprisingly, no systematic analysis of potential mRNA markers for colorectal cancer has been reported. We therefore performed an extensive mRNA marker survey for colorectal cancers.Methods: We identified potential markers through literature and database searches. We analyzed all markers by quantitative reverse transcription-PCR on a limited set of primary tumors and benign lymph nodes. Selected markers were further evaluated on a larger tissue set with positive lymph nodes.Results: We evaluated 43 markers and undertook further analysis of 6 in the secondary screening. Five gene markers—CDX1, carcinoembryonic antigen (CEA), CK20, TACSTD1, and Villin1 (VIL1)—provided perfect classification of lymph node status.Conclusions: Several mRNA markers are capable of providing exceptionally accurate characterization of lymph node status in colorectal cancer. An automated, multimarker, quantitative reverse transcription-PCR assay for characterization of lymph nodes from colorectal cancer patients may be useful for improved staging and therapeutic decision making in colorectal cancer.