Is frozen section reliable in transoral CO2 laser-assisted cordectomies?

Endoscopic resection of laryngeal tumors is replacing external approaches. One drawback of endoscopic resection is the difficulty of interpretation of histological specimens because of thermal effect of laser on tissues. Our goal is to assess the reliability of frozen section in this setting by comparing its results with those of routine histology. We, retrospectively, reviewed the charts of all consecutive patients, who underwent cordectomies in our institution between January 2000 and 2008, using the CO2 laser Acublade system (Lumenis, Santa Clara, CA). Age, sex, staging of the tumor, previous treatments, type of cordectomy, frozen section and routine histology results were analyzed. Ninety-seven patients fulfilled the inclusion criteria; 22.7% had severe dysplasia, 54.6% had T1 epidermoid carcinoma, 17.5% had T2 carcinoma and finally 5.2% had T3 carcinoma. We performed type I cordectomy in 36.1% of patients, type II cordectomy in 18.6%, type III cordectomy in 10.3%, type IV cordectomy in 5.2%, type V cordectomy in 28.9% and type VI cordectomy in 1% of patients. Most of the patients did not have any previous treatment. The mean number of margins per surgery was 2. Routine histological examination confirmed frozen section in 94.8% of the interventions. Frozen section is reliable in laser-assisted cordectomies, when performed by an experienced team; it has a high negative-predictive value. It can limit the need, cost and emotional stress of second look surgeries.