The Contribution of Mediastinal Transbronchial Nodal Cryobiopsy to Morpho-Histological and Molecular Diagnosis.

(1) Background: endobronchial ultrasound-guided mediastinal transbronchial cryo-node biopsy, previously assisted by fine-needle aspiration, is a novel technique of particular interest in the field of lung cancer diagnosis and is of great utility for extrathoracic tumor metastases, lymphomas, and granulomatous diseases. An integrated histological and molecular diagnosis of small samples implies additional difficulty for the pathologist. Additionally, emerging tumor biomarkers create the need to search for new approaches to better manage the tissue sample; (2) Methods: An analytical observational study of 32 mediastinal node cryobiopsies is carried out in 27 patients ( n = 27). Statistical analysis using the t-student and Wilcoxon signed-rank tests for paired data is performed with SPSS 26 and R Statistical software. The significance level is established at p < 0.05; (3) Results: cryobiopsies were valid for diagnosis in 25 of 27 patients, with a maximum average size of 3.5 ± 0.7 mm. A total of 18 samples (66.67%) were positive for malignancy and 9 (33.33%) were benign. The tumor percentage measured in all neoplastic samples was greater than 30%. The average DNA and RNA extracted in nine non-small cell lung cancer cases was 97.2 ± 22.4 ng/µL and 26.6 ± 4.9 ng/µL, respectively; (4) Conclusions: the sample size obtained from an endobronchial ultrasound-guided mediastinal transbronchial cryo-node biopsy facilitates the morphological and histo-architectural assessment of inflammatory and neoplastic pathology. It optimizes molecular tests in the latter due to more tumor cells, DNA, and RNA.