The clinical importance of a transcription reverse-transcription concerted (TRC) diagnosis using peritoneal lavage fluids in gastric cancer with clinical serosal invasion: a prospective, multicenter study.

Purpose. We have developed a novel molecular method of diagnosis using the technique of transcriptase-reverse transcriptase concerted reaction (TRC) for the detection of cancer micrometastasis. This study prospectively examined the clinical importance of the TRC diagnosis with peritoneal lavage fluids collected from gastric cancer operations at multiple institutes. Methods. TRC amplification targeting carcinoembryonic antigen mRNA was applied to detect gastric cancer cells in peritoneal lavage fluids obtained during gastric cancer resections from nine different hospitals. A total of 137 patients with a clinical diagnosis of serosa-invading neoplasms were enrolled to investigate the correlation between the TRC diagnosis and patient prognosis. Results. Of the 137 patients, 27 (20%) were positive by cytologic examination. In contrast, TRC targeting carcinoembryonic antigen mRNA was positive in 59 of 137 (54%) patients. TRC positivity was associated with a poorer overall survival in all patients and in the 104 patients who underwent a curative operation. TRC positivity also was associated with the peritoneal recurrence-free survival rate in the 104 curative cases. Multivariate analysis showed that TRC positivity and the pathologic N factor were prognostic factors for the overall survival time. Conclusion. Our prospective multicenter study showed that the TRC test using peritoneal lavage fluids could be a potential prognostic factor to predict patient survival and peritoneal recurrence with clinically diagnosed, serosa-invading gastric cancer.