THE EFFECT OF FORCEPS SIZE ON THE ADEQUACY OF SPECIMENS OBTAINED BY TRANSBRONCHIAL BIOPSY

This study prospectively compared the diagnostic yield of transbronchi al biopsies using large and small forceps (cup sizes, 3 x 2 x 0.9 vers us 2 x 1.5 x 0.6 mm, respectively). Diagnostic yield was compared by a pathologist, blinded to the size of forceps used on the basis of the relative amount of tissue obtained, alveolar tissue obtained, and abil ity to ascertain a histopathologic diagnosis. Large forceps obtained s ignificantly more tissue than did small forceps (20 of 27 patients [74 %] versus five of 27 patients [19%], p < 0.005, with similar amounts o btained in two patients). Also, large forceps obtained significantly m ore alveolar tissue than did small forceps (16 of 22 patients [73%] ve rsus six of 22 patients [27%], p < 0.05, with no alveolar tissue obtai ned in five patients). In 18 of the 27 patients, biopsies performed re sulted in nonspecific diagnoses, including fibrosis or chronic inflamm ation. All nine of the patients with a specific diagnosis were ultimat ely proved to have sarcoidosis. There was a trend toward more of these patients having noncaseating granulomas obtained with the large force ps than with the small forceps (seven of nine patients versus four of nine patients). No difference was observed in the amount of postbiopsy bleeding with either forceps. We conclude that large forceps used for transbronchial biopsy yield more tissue and more alveolar tissue than do small forceps. These findings may have an impact on the diagnostic yield in some diseases such as sarcoidosis.