Imaging–Histologic Discordance at Percutaneous Biopsy of the Lung

Rationale and Objectives The purpose of this study was to quantify the degree of imaging–histologic discordance in a cohort of patients undergoing computed tomography (CT)–guided lung biopsy for focal lung disease. Materials and Methods A retrospective review was performed of 186 patients who underwent percutaneous lung biopsy of a parenchymal lesion at our institution between January and December 2009. Diagnostic radiology reports of CT or positron emission tomography–CTs performed before biopsy were used to classify the lesion as malignant or benign by five readers. Pathology reports of the biopsied lesions were classified by three readers. Inter-reader agreement and imaging–histologic concordance were quantified using kappa statistics. Discordant benign cases were then revisited to determine downstream effects. Results Inter-reader agreement on report content was substantial or almost perfect with kappas >0.783. Kappas for concordance were as follows: malignant (0.448), primary lung cancer (0.517), metastatic disease to lung (0.449), benign (0.510), and overall agreement (0.381). Of the twelve discordant benign cases that were revisited, four were found to be false negatives, resulting in a delay in diagnosis. Conclusions Our study of imaging–histologic discordance in percutaneous biopsy of lung lesions supports the need for imaging report standardization and improved integration and communication between the fields of radiology and pathology.