Detection of Circulating Tumor Cells by Cell Block Technique in Malignant Tumors

Cancer is a leading cause of death worldwide and is a major cause of morbidity. To deal with this magnitude of cancers and their diagnostic and prognostics, a multitude of prognostic biomarkers for various cancers have been explored over the decades, with detection of circulating tumor cells (CTCs) in the peripheral blood being one of them. This study was undertaken to explore the routine procedure of cell block in the cytopathology lab to isolate and detect CTCs.

In this cross-sectional study, 112 peripheral blood samples sent for routine blood investigations of various cancer patients were utilized for the preparation of cell block. The sections from the cell block were stained routinely and evaluated for the presence of CTCs. The statistical analysis was done using Mac Statplus software version 8.0.

The malignancies were tabulated as per the International Classification of Diseases for Oncology, third edition (ICD-O-3). The maximum number of cases were from C 50 (breast) - 41/112 (36.6%), followed by C15-C26 (Digestive organs) - 19/112 (16.9%), and C00-C14 (lip, oral cavity, and pharynx) - 18/112 (16.07%) cases. CTC was detected in six (5.35%) out of 112 cases, out of which three were from the breast and one each from category C6.9 (mouth), C32.0 (glottis), and C53.8 (cervix uteri).

Among various advanced and molecular techniques available for the detection of CTCs, the cell block technique proves to be one of the effective methods, especially in resource-limited settings as these can further be utilized for additional diagnostic techniques similar to the ones employed for routine paraffin blocks.