Association of syndecan-1 with tumor grade and histology in primary invasive cervical carcinoma

Objectives. The expression of syndecan-1, a cell surface heparan sulfate proteoglycan, is reduced during malignant transformation of squamous cells. Studies on squamous cell carcinoma of the head and neck have shown that syndecan-1-positive tumors are associated with longer overall and recurrence-free survival. The purpose of this study was to analyze syndecan-1 expression in invasive cervical carcinoma and to examine the association of syndecan-1 expression with prognostic factors and overall survival. Methods. The study population consisted of 124 patients treated for primary invasive carcinoma of the uterine cervix at the Turku University Central Hospital during the years 1970-1988. The material consisted of 102 (82.3%) squamous cell carcinomas, 16 (12.9%) adenocarcinomas and 1 (0.8%) adenosquamous carcinoma, 1(0.8%) small cell carcinoma, 1 (0.8%) adenoid basal carcinoma, 1 (0.8%) carcinosarcoma, and 2 (1.6%) unclassified cervical carcinomas. Syndecan-1 expression was determined on paraffin-embedded tissue blocks using a human syndecan-1-specific monoclonal antibody B-B4 and immunohistochemistry. The expression of syndecan-1 was classified according to staining intensity as well as the percentage of positively stained tumor cells. Results. Staining intensity was strong in 44 (36%) samples, while 24 (19%) specimens remained syndecan-1-negative. In 49 (40%) samples, the percentage of syndecan-1-positive cells was greater than or equal to 90%. Syndecan-1 expression, as determined by greater than or equal to 50% positively stained tumor cells, was associated with the grade of differentiation (P = 0.03) and squamous histology (P < 0.001), but was not associated with clinical stage (P = 0.16) or disease-free survival (P = 0.86). Age (P = 0.003) and clinical stage (P < 0.001) were significant prognostic factors, but syndecan-1 expression determined neither by percentage of positively stained tumor cells nor by staining intensity was associated with the outcome. Conclusions. In cervical carcinoma syndecan-1 is associated with histological differentiation grade and squamous histology, but does not predict clinical outcome. (C) 1999 Academic Press.