Ex vivo use of probe-based confocal laser endomicroscopy in lung cancer visualization: an ex vivo pilot study

Lung neoplasia is the main cause of cancer death worldwide, with increasing incidence and an apparent stagnation in the decrease of morbidity. Early lung cancer (LC) diagnosis requires precise pathology and precise surgical intervention at the appropriate time. Current guidelines provide an outline for cancer management, involving multiple imaging methods as well as tissue-collection techniques; however, probe-based confocal laser endomicroscopy (pCLE), although being introduced several years ago, remains an experimental diagnostic method. Based on direct tissue observation that can occur during normal bronchoscopy, with the possibility of combining multiple imaging techniques in a single-step intervention, it however holds great promise. We included 18 consecutive patients diagnosed with LC over a period of six months who underwent curative surgery. After obtaining written consent and ethical approval, we used pCLE on ex vivo tissue samples that were later sent to pathology for confirmation. We then compared pCLE findings with the final pathology diagnosis. We included 12 males, median age in the study group being 64 years. We found 10 adenocarcinomas, four small cell lung carcinomas and four squamous cell carcinomas. The pCLE investigation provided key differentiating aspects between normal lung parenchyma, the structure of elastin fiber distribution and the shape and cellular content of alveoli, as opposed to the anarchic organization of the tumoral tissue. In conclusion, we presented here some of the first descriptive findings of lung tissue in pCLE imaging, thus contributing to the standardization of the technique for diagnostic purposes.