Comprehensive treatment for intracranial invasive sinonasal intestinal‑type adenocarcinoma with a focus on radiotherapy dosage and immunological combination therapy: A case report

For sinonasal intestinal-type adenocarcinoma (ITAC), no standardized treatment exists, particularly for cases with advanced-stage disease with intracranial invasion or recurrence.The present study describes the case of a 60-year-old male patient with ITAC and intracranial invasion who underwent surgery followed by radiotherapy; however, this was terminated early after 25 of 30 sessions [equivalent dose in 2-Gy fractions (EQD2), 54.72 Gy] due to the risk of damaging the optic nerve.The tumor recurred in the same place 12 months after the surgery.A biopsy revealed a combined positive score (CPS) of 5, indicating that the tumor was programmed death-ligand 1-positive (PD-L1-positive), leading to treatment with albumin-bound paclitaxel, cisplatin and camrelizumab for 4 cycles, followed by 12 cycles of maintenance therapy with camrelizumab.The patient maintained progression-free survival for 11 months.On the whole, the present case report highlights the need for sufficient radiotherapy (66 Gy EQD2) for ITAC in complex anatomical areas, highlighting the role of advanced techniques to overcome dose limitations.Moreover, the 'chemo-immuno induction plus immuno-maintenance' approach in PD-L1-positive patients exhibits potential for long-term disease control, providing a novel treatment model for advanced-stage ITAC.