The Rare Case of an Adult-Onset Xanthogranuloma of the Paranasal Sinuses: A Histological Dilemma

Abstract

Xanthogranuloma is a rare benign tumour, part of the non-Langerhans cell histiocytosis group, uncommon in adults and even less common in the paranasal sinuses. Despite its benign nature, it mimics neoplasm due to its local effects which can have serious functional consequences depending on the anatomical location. We present the rare case of a young lady who presented insidiously with a maxillary sinus xanthogranuloma and was treated with endoscopic resection. Tissue diagnosis is of paramount importance to guide correct further investigations and management, and we discuss the potential challenge in identifying such a rarely seen pathology.

Figure 1

Classification of histiocytic disorders based on cell origin (adapted from Li et al.).

Figure 2

Contrast-enhanced CT sinuses (coronal section). Shows right-sided lesion within the nasal cavity associated with bony erosion and slight deviation of the upper aspect of the nasal septum to the left. There is associated complete soft tissue opacification of the frontal sinuses, ethmoidal sinuses, and maxillary sinus. Note the close relationship with the anterior ethmoid artery.

Figure 3

Contrast-enhanced MRI sinuses (coronal section, T2-weighted image). Demonstrates the demarcation between the mass and polypoid maxillary sinus, not appreciated on CT.

Figure 4

Intraoperative endoscopic photograph displaying the soft tissue mass in the right nasal cavity obstructing the middle meatus.

Figure 5

(a) Haematoxylin and eosin stain ×100 magnification: showing sheets of histiocytes with abundant eosinophilic cytoplasm intermingled with polymorphs. (b) Haematoxylin and eosin stain ×100 magnification: showing multinucleate giant cells in the infiltrate (∗). (c) CD68 stain ×200 magnification: highlighting histiocytes (∗). (d) S100 stain ×200 magnification: a giant cell shows engulfed polymorphs in its cytoplasm (∗).

Figure 6

Noncontrast enhanced CT sinuses (coronal section). Postoperative scan demonstrates right ethmoidectomy, middle turbinectomy, and creation of middle meatal antrostomy. Well-aerated sinonasal spaces and no tumour recurrence.