TRANSBRONCHIAL LUNG-BIOPSY - CAN SPECIMEN QUALITY BE PREDICTED AT THETIME OF BIOPSY

Study objectives: To determine the bronchoscopist's ability to predict specimen quality at the time of transbronchial biopsy and to determin e the influence of biopsy specimen size and alveolar content on diagno stic value. Design: Prospective, blinded, observational analysis. Sett ing: Tertiary care academic hospital-based pulmonary practice. Patient s: Forty-three adult patients who underwent transbronchial lung biopsy .Interventions: Each of 170 biopsy specimens was rated as to likelihoo d of containing diagnostic tissue, size and ability to float, tissue t ypes present, number of alveoli, and pathologic diagnosis. Results: Fi fteen percent of biopsy specimens were small and 40% were large. Seven ty-six percent of specimens floated; 81.8% of the 170 biopsy specimens contained abnormal lung tissue; and 14.7% of individual specimens wer e diagnostic. Fifty-two percent of specimens contained >20 alveoli. La rger biopsy specimens were more likely to contain diagnostic tissue (r =0.29, p=0.001). Cup forceps retrieved smaller pieces of tissue (p=0.0 07) and were less likely to obtain diagnostic tissue (p=0.06). Physici an ratings of specimen quality (mean+/-SD) did not differ between spec imens containing normal and abnormal tissue (5.98+/-2.3 vs 5.46+/-5.5; p=0.24) or between specimens containing diagnostic vs nondiagnostic t issue (5.56+/-2.5 vs 6.25+/-2.1; p=0.14). Specimens that floated were no more likely to be diagnostic or abnormal than specimens that sank ( p<0.05). Diagnosis when established was made by the first biopsy speci men in 53.3% and the second in 33.3% Conclusions: Physician estimate o f biopsy specimen quality and the float sign are not helpful in predic ting that the biopsy specimen contains abnormal or diagnostic tissue. Diagnostic biopsy specimen will likely be obtained if the size of the specimen fills the forceps, 2 to 4 biopsies are performed, and toothed forceps are used.