Percutaneous CT-guided biopsy of lytic bone lesions in patients clinically suspected of lung cancer: Diagnostic performances for pathological diagnosis and molecular testing.

Objectives: Bone is a common location for lung cancer metastasis. Clinicians are often reluctant to biopsy bone metastases, as they are known to require a decalcification process that damages nucleic acids, which makes it incompatible with molecular testing. We performed this study to assess the diagnostic performance of histopathology and molecular testing of computed tomography (CT)-guided percutaneous bone biopsies of lytic bone lesions during the initial assessment or during the progression of lung cancer.

Materials And Methods: This retrospective study included all patients suspected of having or known to have primary lung cancer and CT-guided percutaneous bone biopsies of lytic bone from January 2010 to June 2017. The main judgment criterion was the diagnostic performance of the pathological analysis. Secondary endpoints were the diagnostic performance of molecular testing and incidence of complications.

Results: Fifty patients were included. The yield of CT-guided percutaneous bone biopsies for pathological analysis was 100 %, allowing for a diagnosis of certainty in all cases. The percentage of tumor cells in samples was higher than the 20 % threshold in 83.9 % of cases. The yield of molecular analysis was 94.6 %. A mutation was found in 60 % of cases; most frequently in KRAS (Kirsten rat sarcoma viral oncogene homolog) (28.6 %) and EGFR (epidermal growth factor receptor) (14.3 %). The complication rate was 2 %, i.e. a minor undrained pneumothorax.

Conclusion: CT-guided percutaneous biopsies of lytic bone is associated with a very low complication rate and high diagnostic performance for histopathology and mutation testing.