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Aim: To isolate disseminated tumor cells from the bloodstream of patients with transitional cell carcinoma. Material and methods: From 112 patients undergoing chemotherapy, TUR or surgery for transitional cell carcinoma (Ta-T4, G1-G4) in our department we collected a total of 246 samples of 16ml blood by venepuncture ( range 1-10). Samples were collected before and after treatment. The patients` median age was 64.3 years (range 34.8-90.3). The cells were separated on a Ficoll gradient. The mononuclear cell fraction was collected, washed and labelled with anti-CD45 microbeads. After the separation using an autoMACS unit, the CD45 negative cell population was collected on a cytospin device. After gentle centrifugaton, the supernatant was taken off, and the cells were stained with a pan-anticytokeratin antibody. Counterstaining was performed with hemalaun. The slides were evaluated by a trained pathologist. Results: 70 of the 246 (28.5%) contained abnormal cells classified by cytokeratin staining and/or abnormal morphology. The proportion of positive samples was not dependent on T stage nor did it correlate with grading. Patients undergoing chemotherapy for the treatment of more advanced transitional cell carcinoma did not have circulating tumor cells more often in their blood than did patients undergoing surgical procedures. However, pre-operative samples contained tumor cells more often than did post-operative (34.4% vs. 24.2%, p=0.012). This was true for samples from primary and secondary TURs as well as for samples from radical cystectomies.Conclusions: Transurethral resection and radical cystectomy lowered the amount of circulating epithelial cells in the bloodstream of patients with transitional carcinoma.

[Proc Amer Assoc Cancer Res, Volume 46, 2005]