Diagnostic accuracy of CT readings on coin lesions in the lung as compared with transthoracic CT-guided needle biopsy results

Background: The aim of this study was to compare chest CT film reading results with histopathological results after CT-guided transthoracic needle biopsy of the lung. In addition, lung lesion morphology was evaluated and compared with the nature of the lesions.

Patients and methods: Pulmonary lesions of 133 patients who underwent chest CT were retrospectively grouped into benign, malignant or uncertain. All patients underwent CT-guided transthoracic biopsy. Results of CT diagnosis and histopathological evaluation were compared. In addition, CT features such as size, borders, shape and presence of necrosis were assessed and compared with histopathological results.

Results: In 129 patients adequate specimens were obtained. Comparison of CT diagnosis with the histopathological results yielded the following results for chest CT: sensitivity 95%, specificity 43%, positive predictive value 83%, and negative predictive value 75%. Lesions with spiculated margins turned out to be associated with a significantly higher number of malignant lesions than lesions with smooth or blurred margins (p < 0.05). Lesions size, lesion shape as well as the presence of necrosis showed no significant relation to nature of the lesions (p > 0.05).

Conclusion: Radiological assessment of pulmonary lesions alone is not sufficient. the specificity of chest CT is not sufficient to make a definitive diagnosis, i. e., histological verification is still needed for further investigation in a large number of cases. Only lesions with spiculated margins showed a significantly higher number of malignant degenerations in histological evaluation.