A case of high-grade non-intestinal paranasal sinus adenocarcinoma primary in the maxillary sinus: targeted therapy after postoperative immunocombination with chemotherapy

Background High-grade non-intestinal-type sinonasal adenocarcinoma (non-ITAC) is a rare and aggressive form of adenocarcinoma with poor prognosis. The current standard treatment approach involves surgery combined with radiation therapy. However, there is a need for exploring additional treatment modalities to improve patient outcomes. Case presentation We present a case of a 65-year-old male patient who presented with pain in the right maxillary sinus and was diagnosed with high-grade non-ITAC following surgery. Postoperative pathology revealed tumor invasion into bone tissue and vascular invasion, necessitating further treatment. The patient underwent radiation therapy, followed by immunotherapy with carilizumab combined with chemotherapy. During the maintenance immunotherapy period, tumor progression was observed, and genetic testing identified EGFR and TP53 mutations. Consequently, the patient was treated with gefitinib, a targeted therapy drug. Notably, the patient’s lung metastases showed a gradual reduction in size, indicating a favorable treatment response. The patient is currently undergoing oral treatment with gefitinib. Conclusions This case report highlights the potential benefit of combining immunotherapy and targeted therapy in the treatment of high-grade non-ITAC. Despite the rarity of this cancer type, this approach may offer an alternative treatment strategy for patients with this aggressive disease. We hope that this case can contribute to a deeper understanding of high-grade non-ITAC and promote the application of immunotherapy and targeted therapy in improving survival rates for patients with this condition.