口底部MALTリンパ腫から生じたびまん性リンパ腫の1例 A case of diffuse lymphoma arising from MALT lymphoma in the oral floor
We describe a case of malignant lymphoma located in the oral floor of a 72-year-old man. The patient noticed a painless mass in the oral floor, which enlarged slowly over the course of several weeks. He was referred to our department. An elastic, painless, hard tumor, 28×12mm, was located in the right side of the oral floor. Magnetic resonance imaging (T1) showed enhancement of a mass. Gallium scintigraphy showed positive results in the oral floor, but negative results for the other region. A biopsy was performed, and the pathological diagnosis was a suspected MALT lymphoma with a lymphoepithelial lesion in the oral floor.<BR>Tumor resection, including both sublingual glands and the upper layer of the mylohyoid muscle, was performed under general anesthesia.<BR>Histopathological examination revealed diffuse, nodular proliferation of large atypical lymphoid cells with round or indented nuclei and distinct nucleoli. In addition to foci of diffuse proliferations of medium-sized lymphoid cells, lymphoepithelial lesions were present. Immunohistochemical examinations revealed that the atypical cells were positive for CD20, 79a, CD45RO, and Bcl-2, but were negative for CD 10 and <I>Helicobacter pylori</I>. This case was finally diagnosed as a diffuse large B cell lymphoma arising from MALT lymphoma.
日本口腔外科学会雑誌 52(4), 253-256, 2006-04-20
Japanese Society of Oral and Maxillofacial Surgeons