SERUM CONCENTRATION OF CD44 VARIANT-6 AND ITS RELATION TO PROGNOSIS IN PATIENTS WITH GASTRIC-CARCINOMA

BACKGROUND. The expression of variant isoforms of CD44 is correlated w ith the ability of tumor cells to metastasize in some clinical carcino mas. In this study, the serum concentration of soluble splice isoforms of CD44 that shared exon variant 6 (sCD44v6) were measured and the hi stologic expression of CD44v6 in tumors from patients with gastric car cinoma examined. METHODS. Serum samples were obtained from 102 patient s with primary gastric carcinoma before surgery and serum levels of sC D44v6 were determined with an enzyme-linked immunoadsorbent assay. The expression of CD44v6 in tumors was examined by immunohistochemical st aining. RESULTS. Both the serum concentration of sCD44v6 and its expre ssion in tumors were associated significantly with the depth of invasi on of the tumor, lymph node metastasis, and clinical stage in patients with diffuse type gastric carcinoma. Among patients with gastric carc inoma, the serum level of sCD44v6 was higher in those with CD44v6 posi tive tumor cells than in those with CD44v6 negative tumor cells. The s erum level of sCD44v6 was a prognostic indicator in patients with diff use type gastric carcinoma, as was the histologic expression of CD44v6 . However, neither CD44v6 nor sCD44v6 was a predictor of survival time in patients With intestinal type gastric carcinoma. CONCLUSIONS. It a ppears that CD44v6 and sCD44v6 are related to the progression of diffu se type gastric carcinoma. An elevated serum level of sCD44v6 may be u seful as a prognostic indicator in patients with diffuse type gastric carcinoma. (C) 1998 American Cancer Society.