LIHNCS trial: Lugol's iodine in head and neck cancer surgery.

Abstract

e16042 Background: Residual dysplasia at margins of mucosal tumour resection is a cause of disease failure. While risk of transformation of dysplasia is difficult to assess, malignant cells within a field of dysplastic change indicate high transformation potential of this dysplastic field. Lugol's iodine assists in the assessment of surgical margins at tumour resection to ensure removal of margin dysplasia where present and resectable using the surrogate biomarker of glycogen storage. This multicenter RCT assesses efficacy of this technique in head and neck cancer surgery and is recruiting over the next two years. Methods: Patients undergoing primary surgery for oral cavity and oropharynx squamous carcinoma are randomised to gold standard surgical resection or to resection guided by Lugol's iodine application. Mucosal surfaces are irrigated with saline, carbocisteine solution applied to remove surface mucus and then irrigated with Lugol's iodine solution. Where present, adjacent visible surface dyplasia is resected with the tumour specimen. Histopathologists are blinded to the technique used. Histopathology is repeated centrally for quality control. Margin status is assessed for involved, close and clear for carcinoma and for presence of dysplasia at margins. Quality of life data are collected at baseline, six weeks, six, twelve and 24 months. Results: Our cohort study of 100 cases showed a reduction in margin dyplasia from 32% to 4% p<0.001. A feasibility pilot trial recruited 98 patients with 100% consent and data collection rates. Recruitment is progressing on schedule and at time of writing two sites are open. Forty six patients have consented in four sites and are included in the trial to date. A further 12 sites are in the trial set up process. We will report our interim data regarding sites open, screened and consented rates and outcomes so far. Conclusions: To date recruitment is on schedule. We have demonstrated the acceptability of the trial and techniques therein to both patients and surgeons. This is a promising technique which may modify head and neck cancer surgery by targeting dysplasia for inclusion at time of resection of primary cancer. Thus locoregional recurrence may be reduced in a proportion of patients undergoing curative surgical resection.