Predictive Diagnostic Criteria for Diagnosis of Transbronchial Biopsies, Echo-guided by Mini-probe in Peripheral Lung Lesions

The diagnosis of nodules and peripheral lung masses (lesions not accessible in classical bronchial endoscopy) is a challenge for the pulmonologist especially when these lesions are not accessible to the transparietal aspirate under scanner. The overall sensitivity of flexible fibroscopy for peripheral lesions is 69% (bronchial brushing, transbronchial biopsies, bronchoalveolar lavage and blind trans-mucosal aspiration). This sensitivity varies from 33% when the lesion is less than 2 cm, to 62% when it is greater than 2 cm. The puncture under scan of these lesions remains the gold standard. In the meta-analysis of Schreiber G et al., The diagnostic sensitivity of transparietal aspirate for peripheral lung lesions is 90%. On the other hand, the complication rate of this technique is not negligible, with in the study of Boskovic et al, a pneumothorax rate varying from 8 to 64%. In the literature, the only risk factor actually found is the existence of emphysema. However, thoracic drainage is rarely necessary.

Bronchial echo-endoscopy using a radial mini-probe was developed in 1992 by Thomas Hürter and Peter Hanrath to produce ultrasound guided specimens of these peripheral lung lesions. In the meta-analysis of Steinfort et al., The overall sensitivity of this mini-probe technique is 73% for the histological diagnosis. From the same author, a randomized trial compared the diagnostic sensitivity of transparietal aspirate undergoing ultrasound-guided transbronchial biopsy with a radial mini-probe: this was 93.3% versus 87.5% with no significant difference (p = 1 ), Whereas post-procedure complications are less frequent in the ultrasound procedure (27% versus 3%, p = 0.03). Steinfort also showed that the economic cost of bronchial echo-endoscopy by radial mini-probe and transthoracic puncture under CT was similar both to the success or failure of the first procedure requiring further investigations . Mini-probe-guided specimens are therefore an efficient diagnostic alternative to obtain a histological diagnosis of these peripheral lung lesions