Abstract
Invasive sinus aspergillosis is an uncommon but potentially life-threatening infection typically observed in immunocompromised individuals. However, increasing reports highlight its occurrence in patients with transient or borderline immunosuppression. We present a case of a 75-year-old female with treated mantle cell lymphoma and chronic neutropenia who developed invasive sphenoid sinus aspergillosis. Diagnosis was confirmed via imaging and histopathology following surgical intervention. She was treated with liposomal amphotericin B, followed by a successful transition to oral voriconazole, with full clinical recovery. This case underscores the importance of considering fungal sinusitis in patients without classical or sustained immunosuppression and supports a multidisciplinary, stepwise approach to management.