Descriptive analysis of recurrences of nasal intestinal-type adenocarcinomas after radiotherapy

Background Despite adjuvant radiotherapy, rates of recurrences of endoscopically operated nasal intestinal-type adenocarcinomas (ITAC) have not been improved in successive series. To better understand how to improve local control, we aimed to investigate the site of local recurrences of ITACs. Methods Retrospective study in a reference center in sinonasal malignancies. For all patients with a local recurrence, radiotherapy plans were retrieved and compared to the delineation of local recurrences. Results Of 63 patients, 54 underwent adjuvant radiotherapy of which 14 (25.9%) had a local recurrence. Eleven of them had their onset in an optimally irradiated area. Difficulty to dissect the cribriform plate and/or the lateral lamina was reported for 11 patients with local recurrences in the operative reports (p <0.0001). Conclusions Most of recurrences arose in an optimally irradiated area. A close cooperation between surgeons and radiotherapists is required to define areas at risk and adapt treatment.