Objective: Endoscopic ultrasound (EUS)-guided Trucut biopsy (EUS-TCB) has recently emerged as a method that seeks to overcome the limitations of EUS-guided fine needle aspiration (EUS-FNA) by providing a core-tissue specimen needed to increase the yield and accuracy of the diagnosis. The aim of our study was to evaluate whether EUS-TCB adds any information to EUS-FNA in selected patients and to assess the diagnostic yield, overall accuracy and complications of EUS-TCB as compared with EUS-FNA.
Material and methods: The study prospectively included 30 patients who had undergone both procedures.
Results: The yield of adequate tissue harvesting was similar for EUS-FNA and EUS-TCB (96.4% versus 89.3%, p=NS), with the same number of passes done. The diagnostic accuracy of EUS-FNA was also similar to that of EUS-TCB for the diagnosis of malignant mediastinal masses (73.7% versus 68.4%, p=NS). However, the accuracy for obtaining a specific diagnosis was significantly lower for EUS-FNA compared with EUS-TCB (5.3% and 68.4%, p<0.005). EUS-TCB did not appear to help as a rescue procedure in mediastinal tumours, after a false negative result of EUS-FNA. All cases of submucosal tumours were correctly classified by EUS-TCB as gastrointestinal stromal cell tumours (GISTs) or leiomyomas, while EUS-FNA raised only a suspicion of mesenchymal tumour.
Conclusions: EUS-TCB was certainly useful when immunohistochemistry was needed, for example in submucosal tumours and lymphoma, as well as to confirm and characterize the primary or metastatic origin of mediastinal masses. The information provided by EUS-FNA and EUS-TCB is complementary, especially in selected cases where a complete histological diagnosis has an important impact on the clinical management.