Detection of cytokeratin-positive cells in bone marrow in breast cancer and colorectal carcinoma in comparison with other factors of prognosis.

A prospective study is presented in which 293 patients suffering from breast cancer and colorectal carcinoma were analyzed for prognostic relevance of detected isolated disseminated tumor cells in bone marrow (IDTBM). The patients underwent surgery in the period from 1995 to 1997 and remained under observation until 1999. The monoclonal antibody A 45-B/B3 was used in the standard immuno-cytochemical method for detecting IDTBM, which represented an independent prognostic factor for survival time in patients with breast cancer or colorectal cancer. In breast cancer, when IDTBM were detected, the survival period was reduced by at least half. When disseminated tumor cells containing the A45-B/B3 antibody were detected in bone marrow, the risk of an earlier relapse of the tumor increased at least fourfold. In colorectal cancer, detection of IDTBM reduced survival time by a factor of 1.2-4.3. The risk of earlier relapse increased when disseminated tumor cells containing the A45-B/B3 antibody were detected in bone marrow by 2.8-8.1. Therefore, the use of IDTBM as an independent prognostic factor would provide an important method for determining the pathological stage of various cancers. Standardization of this technique into a generally accepted method would be especially desirable in treatment of patients with breast or colorectal cancer.