Transoral laser microsurgery (TLM) for endoscopic excision of head and neck cancers of the upper aerodigestive tract has become an accepted treatment modality. As in any excision of head and neck tumors, the persistance of tumor at the surgical margins influences the outcome. One of the frequent criticisms of endoscopic resection is that the laser use makes interpretation of the surgical margins difficult due to the thermal effect. The goal of this study is to assess the reliability of frozen section after laser excision in locally advanced tumors.

The charts of patients with T2 and T3 tumors, who underwent TLM between January 2000 and 2008, using the CO₂ laser AcuBlade system were reviewed. Frozen section margin results obtained during TLM were compared with margins after formalin fixation.

Sixty-seven patients fulfilled the inclusion criteria. 20 had supraglottic tumors, 22 had oral cavity tumors, 13 had oropharyngeal tumors and 12 had hypopharyngeal tumors. Fifty-nine had no prior treatment, seven had prior radiation therapy and one had prior open surgery. The mean number of frozen margins per surgery was 4. Histological examination on the formalin-fixed tissue confirmed frozen section in 97% of the cases. In 3% of the frozen sections, the diagnosis of invasive carcinoma was missed. None of these patients had significant locoregional disease progression.

Frozen section analysis of margins is reliable during TLM when performed by an experienced team. It enables a one-stage approach reducing the need of a planned second procedure.