Paraffin Sections of Sputum Block: Description of a New Method for Pathological and Molecular Study

Aim: This study was designed to enhance the scope of sputum analysis by using it as a clinical tool in gene/protein expression, by making the paraffin embedded blocks.
Methodology: The specimens were prepared as smear and cell blocks for cytopathologic examination. The preparation of paraffin-embedded block from sputum samples employs fixation and dehydration of the cell specimens. The sputum specimen is first exposed to a suitable fixating agent, Formalin, and graded acetone was employed to dehydrate the samples and saved as pellet. Paraffin blocks containing embedded pellet were taken out gently from the tube. The solidified paraffin-embedded tissue blocks through this novel approach were found to be easy to process for immunohistochemistry and molecular analysis.
Results: Immunohistochemistry staining was performed on paraffin section of sputum block for Cytokeratin (CK) and was found to be easy to process for immunohistochemistry.
Conclusion: The sputum block preparation is feasible and non-invasive, can be useful to identify new biomarkers of exposure or susceptibility in patients with lung pathology to enhance the understanding of airways changes due to different etiological factors and may be useful to find new biomarkers in order to assess and monitor early lung damage.