Purpose: Our previous study demonstrated that a transcription reverse-transcription concerted (TRC) diagnosis using peritoneal lavage fluids at laparotomy was a potential prognostic factor for gastric cancer patients; however, the clinical importance of a TRC diagnosis from peritoneal lavage fluids after lymphadenectomy remains unclear.
Methods: TRC amplification targeting CEA mRNA was utilized to detect free cancer cells before and after lymphadenectomy during gastric cancer resection. Of 120 patients who underwent curative gastrectomy for cT2-T4 gastric cancer, 38 whose peritoneal lavage samples were collected pre- and post-lymphadenectomy were eligible for analysis.
Results: Six (16.0 %) patients had CEA positivity before lymphadenectomy (pre-CEA), whereas nine (23.7 %) had CEA positivity after lymphadenectomy (post-CEA). Post-CEA was significantly correlated with higher pathological N-stage. Moreover, the positive post-CEA group had significantly worse relapse-free survival than the negative post-CEA group (p = 0.001). Cox multivariate analysis revealed that post-CEA positivity was a significant predictor of poor relapse-free survival (p = 0.012). It was also a predictor of distant metastasis, but not specific for peritoneal recurrence.
Conclusions: These findings demonstrated that post-CEA positivity in a TRC diagnosis was a potential predictor of disease recurrence, but not a specific predictor of peritoneal recurrence.
Keywords: CEA; Gastric cancer; Peritoneal lavage fluid; TRC.