CT-guided core needle biopsy of the lung in patients with primary malignancy suspected of lung metastasis: 5-year experience from a single institution

Purpose We aimed to evaluate the diagnostic accuracy and safety profile of computed tomography (CT)-guided percutaneous transthoracic needle biopsy (PTNB) in patients with primary malignancy suspected of lung metastasis and assess possible factors associated with nondiagnostic results. Methods All PTNBs with core needle performed in our hospital from January 2014 to January 2019 were retrospectively reviewed. Overall, 108 cases were found to have a history of primary malignancy with suspected lung metastasis. Patient demographics, lesion characteristics, procedure techniques and complications were evaluated as predictors of overall diagnosis, final diagnosis of lung metastasis, and nondiagnostic results. Statistical analysis was performed using univariate analysis. Results The overall diagnostic accuracy of PTNB was 83.3%. Lung metastasis was found in 52.8% of PTNBs (57 of 108) and nondiagnostic results were present in 27.6% (18 of 108). Of the 18 cases with nondiagnostic results, 11 cases had a final diagnosis of lung metastasis (61.1%), yielding PTNB a sensitivity of 83.8% and specificity of 100% for the detection of lung metastasis. Smaller lesion size (p = 0.014), pneumothorax (p = 0.026), and hemoptysis (p = 0.014) were significantly associated with overall nondiagnostic results. Similarly, smaller lesion size (p = 0.047), pneumothorax (p = 0.019), high-grade pulmonary hemorrhage (p = 0.019), and hemoptysis (p = 0.012) were significantly correlated with unsuccessful biopsies in the diagnosis of lung metastasis. Conclusion CT-guided core needle biopsy of the lung in patients with primary malignancy suspected of lung metastasis has a high diagnostic accuracy with acceptable complication rates. Small lesion size, pneumothorax, high-grade pulmonary hemorrhage, and hemoptysis are significantly associated with nondiagnostic results in the final diagnosis of lung metastasis. Repeat biopsy and clinical/radiological follow-up should be considered in cancer patients with nondiagnostic results due to the high probability of lung metastasis.