COLORECTAL Polymeric Immunoglobulin Receptor Expression is Correlated with Hepatic Metastasis and Poor Prognosis in Colon Carcinoma Patients with Hepatic Metastasis.

Background/aims: Increased expression of polymeric immunoglobulin receptor (pIgR) in tumor tissue has been detected in various cancer forms. However, the clinical relevance of pIgR in colon cancer hepatic metastasis remains uncertain. The aim of this study was to assess the prognostic value of pIgR in patients with colon carcinoma hepatic metastasis after hepatic resection.

Methodology: Genome-wide gene expression analysis was used to evaluate the expression of pIgR in cryopreserved tissue from liver metastases of colon cancer and in the corresponding primary colon cancer tissues from one patient with hepatic metastatic colon cancer. pIgR expression was further confirmed by quantitative real-time PCR in cryopreserved primary colon carcinoma and paired hepatic metastasis tissues from 32 patients with hepatic metastatic colon cancer and by immunohistochemistry in paraffin-embedded primary colon carcinoma and paired hepatic metastasis tissues from 136 patients with liver metastasis from colon carcinoma who underwent hepatic resection. The relation between pIgR expression and clinicopathologic factors and long-term prognosis in these 136 patients was retrospectively examined. The prognostic significance of negative or positive pIgR exspression in colon carcinoma hepatic metastasis was assessed using Kaplan-Meier survival analysis and log-rank tests.

Results: Positive expression of pIgR was correlated with liver metastasis of colon cancer. Univariate analysis indicated significantly worse overall survival (OS) for patients with a positive pIgR expression in colon carcinoma hepatic metastasis than for patients with a negative pIgR expression. Multivariate analysis showed positive-pIgR in colon carcinoma hepatic metastasis to be an independent prognostic factor for OS after hepatic resection (P = 0.021).

Conclusions: Positive expression of pIgR was statistically significantly associated with poor prognosis of patients with colon carcinoma hepatic metastasis. pIgR could be a novel predictor for poor prognosis of patients with colon carcinoma hepatic metastasis after hepatic resection.