Sinonasal Undifferentiated Carcinoma: An Institutional Trend towards Induction Chemotherapy followed by Definitive Chemoradiation

Background: Sinonasal undifferentiated carcinoma (SNUC) is an aggressive locally invasive malignancy of the sinonasal cavity treated by multimodality therapy. Recent reports have investigated the role of induction chemotherapy in the treatment of SNUC. The goal of our study was to ascertain the effects of the addition of induction chemotherapy in the treatment paradigm of SNUC at our institution.

Methods: A retrospective chart analysis of 21 cases of SNUC from 2010 to 2018 at a single institution was performed. A retrospective chart review was conducted including demographic information, disease pathology, patient presenting symptoms, smoking/alcohol history, and surgical, chemotherapy, and radiation treatments utilized. A treatment algorithm was developed based on the data presented in this study and past experience.

Results: The average age at diagnosis was 58.9 years. The most common presenting symptom included nasal obstruction/congestion (47.6%), epistaxis (38.1%), and visual changes/diplopia (38.1%). The average SUV on PET-CT was 35.3. Of the 21 patients in this cohort, 18 (85.7%) presented with T4 disease, 7 (33.3%) presented with nodal disease, and 3 (14.3%) presented with distant metastasis. Six patients underwent surgery, three of six as definitive management, and two of six for decompression of the visual apparatus. Prior to 2016, patients at this institution were managed by multiple Head and Neck teams and multimodality treatment varied from initial surgical management, various combinations of cisplatin and etoposide, and radiotherapy approaches. In 2016, management trended to transfer to a single team that preferred induction chemotherapy consisting of three cycles of docetaxel and cisplatin at 75 mg/m² and fluorouracil at 3,000 to 3,750 mg/m² followed by concurrent chemoradiation. Since 2016, all patients with SNUC were managed using the latter paradigm. To this point, patients treated with TPF induction chemotherapy followed by concurrent chemoradiation show no evidence of disease (mean follow-up of 16.8 months). Of the 17 patients in this study who have completed a full course of chemoradiation, 5 (29.4%) required surgical lysis of adhesions due to synechiae of the nasal cavity. Based on the results of this study and past experience, a treatment algorithm was developed incorporating induction chemotherapy and indications for surgical management ([Fig. 1]).

Conclusion: Multimodality treatment for SNUC has recently begun transitioning, as highlighted by this study, toward increased use of induction chemotherapy rather than initial surgery. Induction chemotherapy may aid in selecting for patients who will respond well to definitive concurrent chemoradiation. This study contributes to a growing body of literature highlighting the use of induction chemotherapy for SNUC.

Fig. 1 Treatment algorithm.