Molecular and immunological detection of circulating tumor cells and micrometastases from solid tumors

Abstract

Histological, immunological, and molecular methods have been used for detecting micrometastases from nonhematopoietic malignancies. Early studies utilizing cytological methods to identify circulating tumor cells demonstrated the uncertain significance of micrometastasis detection for predicting eventual recurrent disease. Recently, reverse transcriptase-polymerase chain reaction (RT-PCR) for the detection of circulating tumor cells has been suggested as a potential technique for staging of cancer. Studies using RT-PCR thus far indicate that test results may be negative in some patients with known metastatic disease, thereby raising doubts about the utility of the method for staging of disease. In this review, we survey the relevant literature and discuss the range of current applications of histological, immunological, and molecular methods for detecting micrometastases from solid tumors in blood, bone marrow, and lymph nodes and the progress toward determining the significance of micrometastasis detection.

Isolated tumor cells in lymph nodes are not a prognostic marker for patients with stage I and stage II colorectal cancer

“…The former method is alleged to have a greater false-positive rate. This is because positive results detected by RT-PCR may not necessarily mean the presence of the tumor cells, but simply indicate the presence of tumor DNA [24,27]. Therefore, IHC staining technique using anticytokeratin monoclonal antibody, as we did in our study, may be the more appropriate method in respect to its simplicity and its speed as well as its low false-positive rate.…”

Detection of TMPRSS2:ERG fusion gene in circulating prostate cancer cells

“…Using genetic and/or biomarkers to detect the CTC might also provide informed treatment planning. With the recent advances in use of specific antibodies and various sorting techniques following antibody labeling, the ratio of epithelial to blood cells can be augmented so that analysis of these cells is more feasible [19][20][21]. However, many genes associated with prostate carcinogenesis are also expressed in hematopoietic cells, and the existence of non-tumor epithelial cells in the peripheral blood complicates CTC analysis [22,23].…”

Detection of circulating tumor cells in breast cancer patients utilizing multiparameter flow cytometry and assessment of the prognosis of patients in different CTCs levels

“…In the past, various immunologic procedures, including immunocytology-and immunohistochemistry-based methods, and reverse transcriptase polymerase chain reaction (RT-PCR), have been used to detect systemic tumor cell contamination (10)(11)(12)(13)(14). Most current methods do not seem to be sensitive or specific enough to detect circulating cells in significant numbers of patients with carcinomas (15)(16)(17).…”