Optical biopsy of nasal cavity cancer with confocal laser endomicroscopy – a pilot study

Nasal cavity carcinoma (NCC) arises in an anatomically and aesthetically critical region. Complete resection with negative margins is mandatory, yet even minimal additional tissue removal may cause substantial cosmetic and functional morbidity and increase the need for reconstruction. This underscores the need for an intraoperative optical biopsy. We report the first evaluation of confocal laser endomicroscopy (CLE) as a potential tool for optical biopsy in NCC. In this pilot feasibility study including six patients, a blinded evaluation of 68 CLE video sequences (34 normal mucosa, 34 tumor), containing 4500 images, was performed independently by three investigators. A previously established scoring system from CLE studies in head and neck squamous cell carcinoma was applied to determine NCC-specific cut-off values and to assess concordance with investigator-based evaluations. Compared with normal mucosa, tumor sequences exhibited greater structural heterogeneity, atypical vascular patterns, increased variation in cell size, and indistinct cell borders. Investigators achieved an average sensitivity of 86.27% ± 9.1 and specificity of 94.13% ± 6.36. The comparison between all expert-based evaluations and all score-based results demonstrated an overall substantial agreement (Fleiss’ kappa: 0.75). CLE appears feasible as an intraoperative optical biopsy in nasal cavity carcinoma. Prospective clinical studies should test clinical utility such as rates of complete resection, defect size, margin sampling efficiency.