Transthoracic Biopsy in the Diagnostic Approach to Mediastinal Masses: Diagnostic Performance, Imaging Guidance and Complication Profile

Aim: To evaluate the diagnostic efficacy, imaging modalities, and complication rates associated with transthoracic needle biopsy for mediastinal lesions, using either fine-needle aspiration biopsy or core needle biopsy under imaging guidance.Materials and Methods: A total of 51 patients who underwent transthoracic needle biopsy for mediastinal masses were retrospectively analyzed. Biopsies were performed under Computed Tomography or Ultrasonography guidance, and the samples were evaluated cytologically or histologically.Results: The diagnostic yield of transthoracic needle biopsy was 86.3% (44/51), with 13.7% (7/51) of procedures being nondiagnostic. The most frequently used needle type was 18G (86.3%). Imaging modalities included Computed Tomography (45.1%) and Ultrasonography (54.9%). Minor complications occurred in two patients: one developed a minor pneumothorax, and another experienced pneumothorax and subcutaneous emphysema. An 18G biopsy needle was used in these patients, and while one of them was performed under ultrasound guidance, the other was performed under Computed Tomography guidance. Pathological diagnoses included thymoma, lymphoma subtypes, metastatic malignancies, and rare benign conditions such as ectopic thyroid tissue and granulomatous inflammation.Conclusions: Transthoracic tru-cut needle biopsy under imaging guidance is a safe and effective diagnostic approach for mediastinal lesions. Imaging features such as necrosis, contrast enhancement, and heterogeneity allow for optimal biopsy site selection, contributing to high diagnostic accuracy and low complication rates.