Detecting recurrent laryngeal carcinoma after radiotherapy: room for improvement

Detecting recurrent laryngeal carcinoma after radiotherapy for a primary tumour can be difficult. Early detection however, is an important prognostic factor. Although a biopsy should be performed in case of clinical suspicion, repeated negative biopsies do not exclude the presence of viable tumour. The trauma caused by biopsies in irradiated tissue may initiate infection, further oedema and failure to heal. We investigated these problems and evaluated the current care and its usefulness. A survey of the current practice concerning diagnostic procedures for detecting recurrent laryngeal carcinoma after radiotherapy in the major institutions treating head and neck cancer in The Netherlands was performed by means of a questionnaire. Furthermore, we performed a comprehensive analysis of the extent and yield of diagnostic work-up in a cohort of patients clinically suspected of a recurrence, who had undergone direct laryngoscopy between 1986 and 1998 in our institution, with a follow-up of at least 6 months. In case of suspected recurrence, 94% of the departments use direct laryngoscopy under general anaesthesia with the taking of biopsies as a diagnostic technique. Imaging does not play an important role. In our department 207 laryngoscopies were evaluated in 131 patients. In 70 patients the first laryngoscopy was negative. Of these initial negative laryngoscopies, 22 (31%) turned out to be false negative within 6 months. Thirty-seven patients remained disease free. They underwent 65 unnecessary laryngoscopies to come to this conclusion. In the decision to perform direct laryngoscopy, the conventional work up leaves room for improvement. Too many unnecessary laryngoscopies are performed. New imaging techniques such as FDG-PET or new applications of CT or MRI may improve the yield of direct laryngoscopy.