S.Khan
Xanthogranuloma is a rare benign tumour, part of the non-Langerhans cell histiocytosis group, uncommon in adults and less common in the paranasal sinuses. Furthermore, it mimics neoplasm due to local effects which can have serious functional consequences depending on anatomical location. A 35 – year – old woman referred to ENT after a mechanical fall and head injury developed sudden onset anosmia, ageusia, and worsening right sided nasal obstruction, discharge intermittently stained with blood, right sided facial pain radiating to right ear and perioral region. Flexible nasendoscopy showed enlarged, edematous right middle turbinate obstructing middle meatus with mucopus in postnasal space. Head and neck examination unremarkable. Urgent contrast CT sinuses showed mass lesion within right nasal cavity causing local expansion and deviation of nasal septum to left with bowing of right medial orbital wall with opacification of sinuses and bony demineralization of adjacent skull base. Contrast MRI sinuses demonstrated lobulated right nasal cavity soft tissue mass involving middle turbinate and uncinate process extending superiorly reaching cribiform plate and olfactory recess but not extending intracranially. Imaging was concerning for aggressive malignant lesion which prompted urgent diagnostic endoscopic resection. Histology revealed polypoid lesion composed of proliferation of large foamy histiocytic cells with variable morphology and immunohistochemistry. Although no evidence of malignancy, histopathological diagnosis could not be reached by several local centers, and expertise sought from histopathologist in Italy concluding that features mostly consistent with xanthogranuloma. Patient remined asymptomatic one year from her excision, and follow-up imaging reassuring. Tissue diagnosis is of paramount importance to guide further investigations and management, we discuss the potential challenge in identifying such a rarely seen unusual pathology.