UTILITY OF ELECTRON-MICROSCOPY IN THE ASSESSMENT OF TRANSTHORACIC NEEDLE LUNG-BIOPSY SPECIMENS

RATIONALE AND OEJECTIVES. The authors determine the usefulness of elec tron microscopy (EM) in the workup of patients with certain intrathora cic masses undergoing transthoracic needle biopsy (TNB). METHODS. Over a 4-year period, 1603 patients underwent TNB at our institution. Of t hese, 79 had EM examination of the aspirated material, The study is a retrospective review of this latter group, Previous use of EM for TNB had suggested that it may be helpful in those with pleural, chest wall , and mediastinal lesions, The 40 men and 39 women had pulmonary (n = 49), mediastinal (n = 17), pleural (n = 10), and chest wall (n = 3) le sions. RESULTS. The adequate specimen rate was 59% (47 of 79) for ligh t microscopy (LM) and 37% (29 of 79) for EM, Of the 28 patients with s atisfactory specimens for both LM and EM, the correct diagnosis was ob tained by LM 79% (22 of 28) and EM 96% (27 of 28) of the time, Electro n microscopy was most helpful in patients with mediastinal (6 of 6 cor rect versus 3 of 6 for LM) and pleural (3 of 3 versus 1 of 3) lesions. CONCLUSIONS. In specific circumstances, EM can be a very useful adjun ct to LM in patients undergoing TNB, Problems with sample adequacy mus t be addressed.