Early detection of peritoneal dissemination of gastrointestinal cancers by reverse-transcriptase polymerase chain...

We examined the usefulness of the reverse-transcriptase polymerase chain reaction (RT-PCR) analysis for E-cadherin mRNA in the early diagnosis of peritoneal dissemination of gastric and colorectal cancers. The RT-PCR analysis was performed on RNA samples extracted from cells which were collected preoperatively from ascites or intraperitoneally infused fluid. E-cadherin mRNA was detected in 2/2 cases (100%) graded into P-1 peritoneal dissemination, indicating the presence of metastatic cells. In the cases with P-2 and P-3 dissemination the gene expression was detected in 2/3 (67%) and 3/5 (60%), respectively. The RT-PCR analysis was more sensitive for P-1 dissemination than cytological examination. These results suggest that determination of E-cadherin gene expression is useful for the early detection of peritoneal dissemination in gastrointestinal cancer because of its high sensitivity and specificity.