Influence of sample number and biopsy site on the histologic diagnosis of diffuse lung disease

Background. Although open biopsy is considered the optimal method for obtaining lung tissue for the diagnosis of diffuse infiltrative pulmonary disorders, there are no universally established guidelines concerning biopsy site selection and the ideal number of tissue samples. Relatively few investigations have been devoted to the influence exerted by the site and number of biopsy samples on the histologic diagnosis. Methods. Seventy-seven open biopsy samples obtained from different lobes of 28 patients with idiopathic pulmonary fibrosis were analyzed. The histopathologic features were evaluated semiquantitatively and the results from each sample compared with those of the other samples obtained from each patient. Results. Statistically significant differences in histopathologic features were not observed between samples. Conclusions. A single generous (2 cm or greater diameter) sample, obtained from a representative region of the radiographically most involved lobe, will suffice for diagnostic and evaluation purposes.