The objective of this study is to study the implications of application of FDG-PET in the selection of patients with suspicion of recurrent laryngeal carcinoma after radiotherapy for direct laryngoscopy with taking of biopsies under general anaesthesia. This involves aspects of accuracy, patient outcomes and associated costs.The research question is: In patients with suspicion on recurrent laryngeal cancer after radiotherapy with curative intent (without obvious signs of tumour) after at least 4 months post treatment and otherwise planned for direct laryngoscopy under general anaesthesia, does a patient selection based on application of FDG-PET reduce the (clinically relevant) number of futile direct laryngoscopies with taking of biopsies under general anaesthesia without increase of incurable recurrences and is it cost-effective compared to a conventional selection based on complaints, physical examination and conventional imaging techniques?The main goal in a policy based on FDG-PET is not a superior sensitivity, but less direct laryngoscopies with an equal sensitivity as compared to the conventional strategy.
research question: In patients at least 4 months after radiotherapy for laryngeal cancer with curative intent (without obvious signs of tumour) in whom direct laryngoscopy with taking of biopsies under general anaesthesia is indicated, does application of FDG-PET reduce the number of futile direct laryngoscopies under general anaesthesia without increase of incurable recurrences and is it cost-effective compared to a conventional selection based on complaints, physical examination and conventional imaging techniques? study design: In a prospective randomized controlled trial two strategy arms are compared: A) Conventional strategy: direct laryngoscopy under general anaesthesia with taking of biopsies; B) FDG-PET based strategy: only direct laryngoscopy under general anaesthesia with taking of biopsies if FDG-PET is positive or equivocal. study population: Patients with clinical suspicion on recurrent T2-T4 laryngeal carcinoma after radiotherapy (without obvious signs of tumour) in whom a direct laryngoscopy under general anaesthesia with taking of biopsies is indicated by the local physician. outcome measures: The primary endpoint is the number of direct laryngoscopies (on a group level) needed to detect (a single) recurrent laryngeal carcinoma. Secondary endpoints are costs, operability of a recurrence, surgical margins of the salvage laryngectomy and quality of life. power/data analysis: The number of direct laryngoscopies in both arms will be determined. Sensitivity, specificity, accuracy, and predictive values will be calculated. The aim is to decrease the number of laryngoscopies with at least 20% to 1.2 per patient.Taken as a significance level of 0.05, a standard deviation for this estimate of 0.5 and a power of 90%, 60 patients per group will be needed. economic evaluation: A cost-effectiveness analysis will be performed.Data on direct medical costs of diagnosing patients and costs per group due to related complications are concurrently collected for both randomization arms. Total costs, based on volume multiplied by full costs, will be calculated and compared.Both life years and quality adjusted life years will be calculated.time schedule: The accrual period is 28 months. Clinical follow-up, data-management, cost-analysis and economic evaluation will take 6 months. Final analysis and preparation of report will take 2 months. The total time of the study is 36 months. |
