Combined analysis of tumor growth pattern and expression of endogenous lectins as a prognostic tool in primary testicular cancer and its lung metastases

Abstract

The aim of this study was to glyco- and immunohistochemically analyze expression of distinct growth/adhesion-related markers of primary testicular carcinomas and their lung metastases in relation to the risk of developing lung metastases and survival of patients, and to correlate immunohistochemical staining profile and syntactic structure analysis in order to delineate new prognostic parameters for this tumor type. Clinical features of 50 patients with primary testicular carcinomas and their corresponding lung metastases were evaluated and compared to those of a control cohort of 25 cases. The set of eight probes including labeled galectins-1 and -3, specific non-cross-reactive antibodies against galectins-1, -3, and -8 as well as anti- Ki-67, anti-bcl-2, and anti-p53 was applied to formalinfixed, paraffin-embedded tumor sections of both primary and metastatic lesions. Syntactic structure analysis computed staining intensities and structural features of the tumor cells. These parameters were set into relation separately and in combination to clinical data including tumor stages, smoking habits, applied cytostatic therapy, disease-free interval, and survival. The risk of testis cancer patients to develop lung metastases depends in descending order on the tumor cell type (non-seminoma versus seminoma), tumor cell heterogeneity (mixed versus monomorphous cell type), age of patients, and pT stage. The extent of differential expression of galectinrelated features between primary and secondary lesions was pronounced. Prognostic correlations for distinct galectin-related features were delineated in combination with data from syntactic structure analysis, for example cluster radius of galectin-3-positive tumor cells and postsurgical and total survival. Lengths of disease-free interval and total survival of patients were also correlated to characteristics obtained by syntactic structure analysis and their combination with galectin data in the first place, then to smoking habits, percentage of proliferating cells in the primary and secondary tumors, and finally to expression of certain galectins and of p53. Patients with non-seminoma testicular cancer should be thoroughly controlled for lung metastases. Regarding marker selection, our study underscores that further investigation of the growth-regulatory network of galectins is clearly warranted.