Weak stromal Caveolin-1 expression in colorectal liver metastases predicts poor prognosis after hepatectomy for liver-only colorectal metastases.

Loss of stromal Caveolin-1 (CAV1) expression is associated with poor prognosis in various cancers. We evaluated the prognostic value of CAV1 expression of both cancer cells and stromal cells in colorectal liver metastases (CRLM) in patients undergoing hepatectomy. In this retrospective study, 109 patients were enrolled. CAV1 expression was studied by immunohistochemistry. The staining was scored semiquantitatively as weak or strong. Disease-free survival (DFS) and overall survival (OS) were calculated using both Kaplan-Meier and multivariate Coxregression methods. Weak stromal CAV1 expression was associated with decreased DFS and OS in univariate and in multivariate analysis (HR 2.00; 95% CI, 1.24-3.22; P = 0.004, and HR 2.47; 95% CI, 1.28-4.76; P = 0.007, respectively). Cancer cell CAV1 expression was not associated with DFS and OS. Five-year DFS and OS rates were 13% and 43%, respectively, in patients with weak stromal CAV1 expression and 40% and 71%, respectively, in patients with strong stromal CAV1 expression. In this study, we indicate that weak stromal CAV1 expression in CRLM is an adverse prognostic factor in patients who undergo liver resection for liver-only colorectal metastases. We suggest validation of this finding in an independent cohort and consideration of risk stratification for post-hepatectomy adjuvant follow-up and therapy.