Role of Cell Block in Diagnostics-A New Paradigm in Cancer Diagnosis

The two ends of spectrum benign to malignant pose no problem, however in the middle lies a “no man’s land” where wise men tread cautiously. Surgical Pathology and Cytopathology are the main stay in the tumor diagnosis. However, newer technologies like-Immunohistochemistry, Molecular diagnosis, Flowcytometry and Tumor markers introduced in the past decade, have contributed immensely towards achieving accuracy of diagnosis [1]. It has been found that the examination of cytologic material for evidence of malignant neoplasm by the cell block technique is an eminently worthwhile and dependable procedure provided suitable methods and proper diagnostic criteria are provided [2,3]. The improved availability of Immuno Histochemical (IHC) stains in recent years has also increased the desire for cell block preparation in cytopathology laboratories because, larger numbers of initial diagnoses of today are being evaluated by fine needle aspiration versus the past, when a biopsy or resection was available to the pathologist [4]. Contrary to the attempt to single out smear or cell block as being superior to the other, the main aim of this study was to access the utility of cell block in increasing the cytodiagnosis of fine needle aspirates and fluids and to apply immuno histochemical markers on cell blocks and evaluate whether the cell block material fixed in 10% formalin, is suitable for immunohistochemistry (IHC). It has been seen in various studies that the cytologic examination of fluids and fine needle aspirates by means of smears, no matter how carefully prepared, leaves behind a large residue that is not further investigated and that might contain valuable diagnostic material and this residual material can be evaluated in a simple and expedient fashion by treating it as a cell block, embedded in paraffin and examined in addition to the routine smears [5,6]. The utility of cell blocks in comparison to smears is immense for observing architecture parallels which cannot be observed in cyto smears. Moreover IHC stains can be performed on cell blocks more successfully [7]. The main aim of this study was to access the utility of cell blocks in increasing the cytodiagnosis of fine needle aspirates and fluids and to apply IHC markers to enhance diagnosis.