Non-Hodgkin's lymphomas are a group of highly diverse malignancies and have great tendency to affect organs and tissues that do not ordinarily contain lymphoid cells. 20 to 30% of non-Hodgkin’s lymphoma arise from extranodal sites [7
]. The head and neck is the second most common region for extranodal lymphoma after gastrointestinal tract [8
]. Among various head and neck sites, Waldeyer's ring, which is an area encompassed by the nasopharynx, the tonsil and the base of the tongue is most often involved by malignant lymphoma [10
]. The nose and paranasal sinuses, orbit(s), salivary glands are other sites in head and neck affected in descending order of frequency [12
]. Involvement of various parts of the oral cavity is very uncommon [4
]. The gingiva and the hard palate are the most often involved intraoral sites [13
]. Involvement of buccal mucosa, oral tongue, floor of mouth and lip(s) has been reported quite infrequently. To date, only 12 cases of the non-Hodgkin’s lymphoma of the oral tongue has been mentioned in the literature [1
]. This is the first case of non-Hodgkin's lymphoma of the oral tongue being reported from India.
Little is known about the etiological factors for primary lymphoma of the oral region. Few cases of oral lymphomas have been reported in association with Acquired Immune Deficiency Syndrome (AIDS), and it may even be the first presentation of the disease in certain individuals [14-16]. It generally affects the elderly, especially over the 6th decade of life . Our patient was 30-year-old woman. There are no characteristic clinical features of non-Hodgkin’s lymphoma of the oral region. The most common presenting symptoms are local swelling, pain or discomfort and ulcer. The oral non-Hodgkin’s lymphoma may mimic more commonly benign oral and dental pathologic conditions . Thus, these lesions may be easily misdiagnosed. Awareness of this clinical entity in the oral region is important because lymphomas and more common malignant lesions such as carcinomas can not be differentiated clinically. Most of the head and neck non-Hodgkin's lymphomas including oral lesions are of B-cell origin and diffuse large cell type being the most common . The present patient had diffuse T-cell variety, large cell type non-Hodgkin’s lymphoma.
The paucity of cases makes the understanding of the biological behaviour and therapeutic options of lymphoma involving the oral region difficult. Like lymphomas at other head and neck sites, oral lesions also seem to be quite sensitive to both radiotherapy and chemotherapy. Our patient was treated with chemotherapy and radiotherapy following excision of the lesion as histopathology proved it to be a high grade lymphoma. She remained without evidence of disease 15-months after her treatment. The overall prognosis of non-Hodgkin's lymphoma is related to the stage of tumor and aggressiveness of the malignant cell type. In conclusion, though non-Hodgkin's lymphoma involving oral region is uncommon, it should always be considered in differential diagnosis of various benign and malignant lesions in this region, because the treatment and prognosis for these conditions are quite different. A proper clinical evaluation, histopathologic as well as immunohistochemical evaluation of biopsy specimen may aid in the diagnosis and thus, help in proper management.