CT features and pathologic characteristics of IgG4-related systemic disease of submandibular gland

The submandibular gland is one of the most frequently affected salivary gland in IgG4-related systemic disease, usually demonstrate homogeneous attenuation on CT imaging as reported, but without much pathological comparison of many cases. This article is to investigate and analyze the typical CT findings and pathologic characteristics of IgG4-related systemic disease (IgG4-RSD) of submandibular gland. A retrospective analysis of the preoperative CT findings in patients with IgG4-RSD of submandibular glands who underwent surgical resection between January 2010 and February 2014 was performed. Twenty patients (16 women) were identified, with a mean age of 58.1±10.2 years. All patients presented with painless submandibular gland swelling. Diffuse gland enlargement, with clear margins and homogeneous density, was found on non-enhanced CT scans in all cases. There were no calcifications or stones within the involved glands. Based on contrast-enhanced CT appearance the patients could be divided into two groups: 11 cases showed homogeneous gland enhancement; and multiple hyperenhancing foci, with a crazy-paving pattern, were detected in 9 cases, which were in consistent with the pathologic findings. The maximum submandibular gland diameter on transverse images was significantly larger (P=0.008) in patients with crazy-paving appearance (32±4 mm) compared to patients with homogeneous enhancement (28±3 mm). It is concluded that the submandibular glands with IgG4-RSD can be characterized by either homogenous appearance or crazy-paving pattern on contrast-enhanced CT imaging.