Unusual cause of maxillary sinus mass with proptosis

Abstract

We report a case of a 21-year-old Indian man with an 8-month history of left-sided headache, maxillary sinus mass, proptosis and swelling of the left temple, whose contrast-enhanced CT scans of the paranasal sinuses showed an enhancing, destructive soft tissue mass involving the left maxillary sinus, orbit, infratemporal fossa and anterior cranial fossa, suggestive of a malignancy or chronic granulomatous disease. Histopathological examination of the sinus mass, which was debulked and partially excised via an endoscopic approach, suggested a diagnosis of immunoglobulin G4-related sclerosing disease of the maxillary sinus. Subsequent immunohistochemical staining and biochemical tests confirmed the diagnosis. We highlight the importance of considering this increasingly recognised but rare entity that can mimic a malignant lesion with its clinical and radiological features but which, unlike the latter, has a very good prognosis with appropriate treatment.

Figure 1

(A and B) Contrast-enhanced coronal and axial CT sections of the paranasal sinus showing an ill-defined enhancing mass (black arrow) within the left nasal cavity, and maxillary sinus eroding the floor of orbit and extending to the left infratemporal fossa.

Figure 2

(A–C) Photomicrography of immunoglobulin G4 (IgG4)-related sclerosing disease. (A) H&E staining ×200 showing dense lymphoplasmacytic infiltration (thin red arrow), sclerosing fibrosis (thick red arrow) and obliterative phlebitis (thin black arrow). Immunohistochemistry shows brown staining of (B) IgG4-positive cells (arrow) and (C) IgG-positive cells (arrow). The ratio of IgG4/IgG-positive plasma cells is >70% and the IgG4-positive plasma cell count was 60–70/high-power field.

Figure 3

(A and B) Contrast-enhanced coronal and axial CT scan sections of the paranasal sinus on follow-up after 3 months showing a reduction in the mass in the nasal cavity, middle meatus and infratemporal regions.