Clinicopathology significance of podoplanin immunoreactivity in esophageal squamous cell carcinoma.

BACKGROUD AND AIM

Podoplanin (D2-40) is a specific marker for lymphatic endothelium. The vast majority of previous studies on podoplanin immunostaining in esophageal squamous cell carcinoma (ESCC) focused on identifying lymphatic vessel invasion (LVI) and counting lymphatic vessel density (LVD) and had contradictory results. Recent studies show podoplanin expression on cancer cells or tumor stroma in several cancers, which have specific significance; but the status in ESCC remains unclear. Therefore, the aim of this study was to further study and summarize the clinicopathological significance of podoplanin immunoreactivity in ESCC.

MATERIALS AND METHODS

We examined podoplanin expression in tissue specimens from 107 patients with ESCC by immunohistochemistry. Podoplanin positive lymphatic vessels in intratumoral and peritumoral tissues and podoplanin positive expression in cancer cells and tumor stroma were analyzed, and correlated with clinicopathologic parameters and three-year overall and free-disease survival.

RESULTS

34 (31.8%) and 28 (26.2%) of 107 specimens had podoplanin positive expression in cancer cells and tumor stroma, respectively. Logistic regression analysis showed high intratumoral lymphatic vessel density (I-LVD) and podoplanin positivity in cancer cells were increased risks of lymph node metastasis (LNM) (OR=2.45, P=0.03; OR=0.35, P=0.01, respectively). Survival analysis showed that I-LVD was a significant factor related to poor three-year overall and free-disease survival (P=0.04, P=0.03, respectively).

CONCLUSIONS

Previous data and our results show that podoplanin seems to be a useful marker to predict LNM, recurrence, and worse prognosis in ESCC; in particular, LVI, high I-LVD, and podoplanin positivity in cancer cells are associated with LNM, recurrence and overall survival.