Sinonasal intestinal-type adenocarcinoma: outcomes and adverse prognostic factors from a single-institution experience

Purpose: Sinonasal intestinal-type adenocarcinoma (ITAC) is a rare malignancy with high recurrence rates and significant morbidity. This study evaluates survival outcomes and prognostic factors—particularly the impact of tumor stage (pT category), histologic grade, and resection margins—in a contemporary institutional series. Methods: A retrospective analysis included 30 patients treated for histologically confirmed sinonasal ITAC at a single centre from July 2010 to July 2024. Patient demographics, tumor characteristics, treatment strategies (including surgical approach and perioperative therapies), and outcomes were reviewed. Kaplan–Meier analyses were used to estimate overall (OS), disease-specific (DSS), and disease-free survival (DFS). Results: The study cohort comprised predominantly male patients (86.7%), with a mean age of 66 years. Advanced disease (pT3 and pT4) occurred in 66.7% of patients. The median follow-up was 53 months. Five-year OS was 58.6%, DSS 75.3%, and DFS 65.3%. Early-stage tumors (pT1 and pT2) demonstrated superior outcomes, achieving 100% five-year OS and DSS compared to 41.7% OS and 62.9% DSS for advanced stages (p < 0.05). Conclusion: Pathological T category remains a key prognostic determinant in sinonasal ITAC. Endoscopic resection, including transnasal craniectomy when necessary, coupled with risk-adapted radiotherapy, yields favorable survival outcomes even in advanced cases.