Prognostic relevance of disseminated tumour cells in bone marrow of patients with transitional cell carcinoma

Objective: This prospective study is the first immunocytochemical investigation of the frequency and prognostic value of CK+ tumour cells in the bone marrow of patients with transitional cell carcinoma (TCC). Methods: Bone marrow aspirates from 228 TCC patients were taken preoperatively. Cytospins were made and stained by immunocytochemistry using the monoclonal antibodies CK2 and A45-B/B3. 27 patients with no evidence of any malignant disease served as control group. Results: CK+ tumour cells were detected in 28% (63/228) of the TCC patients. No CK+ cells (0/27) were detected in the control group. In multivariate analysis the detection of ≥3 CK+ cells in bone marrow was an independent prognostic factor (hazard ratio = 2.7, p < 0.05) in patients with T2-4 tumour classification. Conclusion: Disseminated CK+ cells play a role in the biology of tumour spread of TCC, and their immunocytochemical detection can be useful in assessing the prognosis of TCC patients with an invasive tumour.