Survival of Patients with Sinonasal Cancers in a Population-Based Registry, Lombardy, Italy, 2008-2023

Simple Summary Sinonasal cancers (SNCs) are rare tumours of the nasal cavity and paranasal sinuses with recognised or suspected associations with some occupational carcinogens, including wood and leather dusts and nickel and chromium compounds. In Italy, a population-based SNC registry organised as a network of regional registries was officially established in 2008 to monitor SNC occurrence and evaluate occupational exposure. In this study, we analysed survival of SNC patients based on the SNC registry of the Lombardy region, north-west Italy (10 million people, one-sixth of the Italian population). In 2008-2020, we recorded more than 800 cases. Vital status was determined until mid-2023. About 50% of patients died within 5 years of diagnosis. Survival was strongly dependent on patients' age (worst prognosis in the elderly), tumour location (worst prognosis for paranasal sinuses), and for some histological types. Survival has not improved in recent years. Women and men had a similar prognosis.Abstract Sinonasal cancers (SNCs) are rare malignancies associated with occupational exposures. The aim of this study was to analyse the survival of SNC patients using data from the population-based SNC registry of the Lombardy region (10 million people), Italy. We included epithelial SNC cases registered in 2008-2020 and followed-up for vital status until 31 July 2023. Multivariate flexible parametric models with time-dependent covariates were fitted to calculate excess hazard ratios (EHRs) and 95% confidence intervals (CIs) of death. Based on 827 cases (553 males, 274 females) and 514 deaths (345 males, 169 females), the 5-year observed survival was 49% and the net survival was 57%. Age had a substantial impact on survival, particularly within the first year (EHR, 1.35; 95% CI, 1.12-1.51 per 10 years). Compared with the nasal cavity, the EHR for paranasal sinuses was 4.70 (95% CI, 2.96-7.47) soon after diagnosis. Compared with squamous cell carcinomas, the EHR was 0.69 (95% CI, 0.52-0.91) for adenocarcinomas, 1.68 (95% CI, 1.20-2.35) for undifferentiated and unspecified carcinomas, and 1.78 (95% CI, 1.07-2.95) for neuroendocrine carcinomas. Age and cancer site showed time-dependent effects on prognosis, especially within the first month after diagnosis. Prognosis was also markedly affected by cancer morphology. No associations were found for gender and period of diagnosis.