Filtration and agar embedding applied to fine needle aspirates for tumor diagnosis by electron microscopy - A combined technique

OBJECTIVE: To develop a novel method for processing of fine needle aspirate s subjected to electron microscopic (EM) study. STUDY DESIGN: Included 70 cases of poorly differentiated malignant tumors i n which a definitive diagnosis was not possible on light microscopic (LM) e xamination and that thus required application of an ancillary technique suc h as FNA/EM for diagnosis. We have established a novel method of processing , a technique of filtration through nylon mesh filters to eliminate red blo od cells (RBCs) and necrotic debris,followed by agar well embedding to avoi d loss of diagnostic material during processing without centrifugation at l ater steps after agar embedding, thus minimizing the time required for proc essing. It was successfully carried out in 70 cases. RESULTS: The combined technique was extremely effective in eliminating RBCs and necrotic debris. It also avoided further loss of valuable diagnostic m aterial. All accurate diagnosis was rendered in 70 cases; that was not poss ible by LM alone. The whole procedure saves two to three hours of processin g as centrifugation is not required after the agar embedding step. CONCLUSION: This technique tons found to be cost- and time-effective, parti cularly suitable for developing countries, where financial resources are li mited.