Introduction: Sinonasal carcinomas are a rare type of head and neck malignancy with various histologies. The outcomes of patients with unresectable locally advanced sinonasal carcinomas are poor. Hence, we performed this analysis to study the long-term outcomes of sinonasal adenocarcinoma (SNAC) and sinonasal undifferentiated carcinomas (SNUC) where neoadjuvant chemotherapy (NACT) has been given followed by local therapy.

Methods: 16 patients with SNUC and adenocarcinoma who received NACT were found eligible for the study. Descriptive statistical analysis was performed for baseline characteristics, adverse events and treatment compliance. Kaplan Meir methods were used for the estimation of progression-free survival (PFS) and overall survival (OS).

Results: Seven (43.75%) adenocarcinoma and nine (56.25%) SNUC patients were identified. The median age of the whole cohort was 48.5 years. The median number of cycles delivered was 3 (IQR 1–8). The incidence of grade 3–4 toxicity (CTCAE version 5.0) was 18.75%. The response was partial response or better in seven patients (43.75%). Post-NACT 11 patients (n = 15, 73%) were eligible for definitive therapy. The median PFS was 7.63 months (95% CI, 3.23 – NA months) and the median OS was 10.6 months (95% CI, 5.2–51.5 months). Median PFS and OS for those who underwent surgery post-NACT versus those who did not undergo surgery were 36.267 versus 3.7 months (p = 0.012) and 51.5 versus 10.633 months (p = 0.190), respectively.

Conclusion: The study shows a favourable role of NACT in improving resectability, significant improvement in PFS and non-significant improvement in OS after surgery.