Intraoral presentation of anaplastic large T cell lymphoma
Anaplastic large T cell lymphoma involving oral cavity is initially identified as enlargements of the gingiva. This type of lymphoma occurrence in the oral mucosa is rare and not well documented. Anaplastic large T cell lymphoma is characterized by cellular pleomorphism and sinusoidal growth pattern. It revealed variable immunohistochemical pattern. We report a case of anaplastic large T cell lymphoma that 74 years-old Japanese woman with the enlargement of gingiva in upper and lower jaws. The mass had been present for three months and has not respond to a 1-week course of antibiotics. In palpation, lymph nodes were identified as elastic hard and small red-bean size in both light and left sub-mandibular area. A radiograph showed marked alveolar bone absorptions related to periodontitis in the upper and lower jaw with overlying soft tissue mass. An incisional biopy of the soft tissue enlargements was performed. The surgical specimen revealed an intact epithelial covering with diffuse proliferations of large pleomorphic cells within submucosa. These tumor cells showed ovoid nucleus with dispersed chromatin, prominent irregularly shaped nucleoli and observed a high frequency of mitosis. Immunohistochemical studies were carried out with 10% neutral buffered-formalin fixed, paraffin embedded tissue using CSAII kit according to the manufacture’s instructions (DAKO). The majority of tumor cells stained strong positively for CD30, Ki-67, Vimentin, and positively for CD3 and CD45RO. While, tumor cells stained negatively for EMA, CD20, CD56, CD79a, Kappa chain, lambda chain and immunoglobulins. The staining result obtained anaplastic large T cell lymphoma, unless negative stained for EMA. Although involving oral mucosa id extremely rear, anaplastic large T cell lymphoma should be included in the different diagnosis and required immunohistochemical analysis to eliminate other malignant lesions.