Tortoiseshell Appearance of Bilateral Submandibular Glands by Infiltration of Mucosa-Associated Lymphoid Tissue Lymphoma

Abstract

The cervical mass is one of the major initial manifestations of various histologic subtypes of malignant lymphoma. In addition to the diagnosis of malignant lymphoma, the differential diagnosis of its nature is increasingly important in the care of patients because of recent advancements in therapeutics based on elucidation of its molecular pathogenesis. Mucosa-associated lymphoid tissue (MALT) lymphoma constitutes 7% to 8% of all B-cell lymphoma and up to 50% of primary gastric lymphoma, but it can develop in other sites, including the lung and superficial organs such as the head and neck, ocular adnexa, skin, thyroid, and breast. 1 Lymphoma of the salivary glands in patients with Sjogren syndrome and other autoimmune disorders is usually MALT lymphoma, whereas its histological subtypes in patients without such underlying disorders are various, with follicular lymphoma the most common and MALT lymphoma on rare occasions. 2 With recent advancements in sonographic technology and devices, sonography has become widely used in the diagnosis of masses in the superficial organs, including the cervical area. 3-6 Sonography of lymphomatous involvement of salivary glands has been reported as showing a hypoechoic or cystic mass, regardless of the histologic subtype. 7-11 We found involvement of bilateral submandibular glands by MALT lymphoma cells in a patient without Sjogren syndrome, which sonographically showed an unusual tortoiseshell pattern. Here we discuss the importance of the internal echo texture in the differential diagnosis and its implication in involvement of the submandibular glands by MALT lymphoma.