悪性リンパ腫の精査中に発見され鑑別診断が困難であった頚部嚢胞性リンパ管腫の1例

Abstract

We report a case of cervical cystic lymphangioma that was found during the examination of malignant lymphoma and difficult to differentiate from malignant lymphoma. A 68-year-old man with chronic hepatitis type C developed a subcutaneous mass at his posterior cervical region and this slow-growing tumor was resected and diagnosed histologically as non-Hodgkin lymphoma (diffuse mixed, B cell type). Although no other superficial lymph nodes were palpable, ultrasonography (US) of the neck revealed a low echoic mass of 40mm×30mm in diameter at the left supraclavicular fossa. The computed tomography (CT) also showed an inhomogeneously enhanced mass at the same region. On magnetic resonance imaging (MRI), T1-weighted image showed a low intensity mass and T2-weighted image showed a high intensity mass. The mass was enhanced inhomogeneously by systemic infusion of gadolinium. Therefore, the differential diagnosis from malignant lymphoma was difficult. The mass was resected and finally diagnosed as cystic lymphangioma. Cervical lymphangioma is rare among adults. Because US, CT and MRI examinations cannot provide definite information, the final diagnosis is usually made by histological examination of the resected specimens. In this case, the mass was found at the supra- clavicular fossa near the malignant lymphoma. Therefore, the histological differential diagnosis from malignant lymphoma was extremely important.