211 - "Precision in the Mediastinum- an Insight into the CT-guided Biopsy Accuracy and Safety

Purpose: The mediastinum can harbor a wide range of pathological conditions and histopathology is musr before treatment. CT-guided percutaneous biopsy is widely used for tissue diagnosis. This study evaluated the diagnostic accuracy, safety, and factors influencing yield of CT-guided mediastinal biopsy, with emphasis on rapid on-site evaluation (ROSE).

Materials and Methods: In an IRB-approved retrospective study, which included 350 patients who underwent CT-guided mediastinal biopsy from January 2019 to June 2024. Rapid On-Site Evaluation (ROSE) was used as a critical adjunct providing real-time assessment of specimen adequacy. The diagnostic yield and accuracy for the biopsy were calculated. Positive predictive value (PPV), Negative predictive value (NPV), sensitivity, and specificity were calculated. In addition, patient demographics, procedure-related factors, imaging-related factors, diagnosis-related factors and post-procedure-related factors were studied.

Results: Diagnostic accuracy was 97.1% with a yield of 93.4%. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 96.9%, 100%, 100%, and 55%, respectively. Diagnostic yield was significantly associated with technically targeted biopsies (p < 0.001), lesion size (p = 0.03), number of cores (p = 0.05), repeat procedures (p = 0.02), PET avidity (p = 0.01), and ROSE use (p < 0.001). ROSE was performed in 34 cases (11.1%), with 28 concordant with final histopathology; its use was significantly associated with diagnostic accuracy (p = 0.01). No major complications occurred. Minor (Grade A/B) events were seen in 12 patients (3.9%), Grade C in 2 (0.7%), and Grade D in 1 (0.3%), all managed successfully.


Conclusion: CT-guided mediastinal biopsy is accurate, safe, and reliable, with low complication rates. ROSE improves diagnostic precision, reduces needle passes, and expedites diagnosis. Findings are consistent with international standards, supporting CT-guided biopsy as the primary diagnostic tool for mediastinal lesions.