Expression of SSEA-1 carbohydrate antigen correlates with stage, grade and metastatic potential of transitional cell carcinoma of the bladder.

Expression of stage-specific embryonic antigen-1 (SSEA-1) was immunohistochemically analyzed in primary cancerous regions from transitional cell carcinoma of the bladder. Lymph node metastasis occurred in 14 (50%) of 28 patients with high expression of SSEA-1 antigen, but in only one (4%) of 23 patients with low or no expression. Of 36 invasive bladder carcinoma patients with no metastasis at operation, 8 (57%) of 14 with high expression of SSEA-1 antigen died of cancer or had metastasis, whereas 4 (18%) of 22 with low or no expression had progression of the disease. In addition, stage pT3b-4 tumors more frequently reacted with SSEA-1 MAb than stage pT1 tumors (p less than 0.01). Grade 2 or 3 tumors were also more reactive than grade 1 tumors, which were all unreactive except for one (p less than 0.01, respectively). Our data suggest that SSEA-1, which is a Le(x) antigen, correlates with stage and grade as well as metastatic phenotype of transitional cell carcinoma of the bladder.