Burkitt's lymphoma of the base of the tongue: a case report and review of the literature

Ear, Nose & Throat Journal, June, 2007 by Steven M. Feinberg, S.H. Ignatius Ou, Mai Gu, Terry Y. Shibuya

Abstract

Burkitt's lymphoma is a highly aggressive, mature B cell non-Hodgkin's lymphoma that is rare outside Africa. We report a case of Burkitt's lymphoma presenting as a rapidly expanding tongue-base mass that caused airway obstruction in an 80-year-old Palestinian man living in California. According to our review of the literature, this is only the third reported case of Burkitt's lymphoma arising in the base of the tongue. We also discuss the incidence, epidemiology, genetics, prognosis, and treatment of this malignancy. Because Burkitt's lymphoma is one of the fastest-growing tumors in humans, rapid diagnosis and treatment are important. Treatment involves brief-duration, high-intensity chemotherapy and central nervous system prophylaxis. It is important for the otolaryngologist to recognize this disease and to understand the steps necessary to treat this aggressive tumor.

Introduction

Burkitt's lymphoma is a highly aggressive, mature B cell non-Hodgkin's lymphoma. It appears in three variant forms: endemic, sporadic, and immunodeficiency-associated. In all three variants, the c-myc oncogene is activated via a specific chromosomal translocation that results in disordered cell proliferation.

The tongue base is an extremely rare location for this tumor. To the best of our knowledge, only 2 cases have been previously reported in the English-language literature. (1,2) In this article, we report the third such case.

Case report

An 80-year-old Palestinian man presented to our clinic with a 3-month history of a muffled voice, odynophagia, cough, and snoring. Physical examination revealed that alarge mass had arisen from the right side of the base of the tongue; the mass crossed the midline and extended to the vallecula. On computed tomography (CT) of the tongue base, the mass measured 4.3 x 2.4 x 2.8 cm (figure 1, A).

[FIGURE 1 OMITTED]

The patient underwent local tracheotomy and endoscopy (figure 2) with biopsies. Pathologic examination of the biopsy specimens revealed a diffuse monomorphous population of small and medium-size lymphocytes with round to oval nuclei, prominent basophilic nucleoli, coarse chromatin, and a thick nuclear membrane; abundant mitotic figures and tingible-body macrophages were easily identified, giving rise to the classic "starry-sky" appearance (figure 3). A moderate amount of amphophilic cytoplasm was identifiable. Flow cytometry demonstrated expression of CD10, CD19, and CD20 antigens with monoclonal restriction of the lambda light chain. Tumor staging was performed on the basis of findings on lumbar puncture, bone marrow biopsy, liver function tests, chest x-ray, positron-emission tomography (PET), and CT of the head, chest, abdomen, and pelvis. All staging workups were negative (including a normal lactate dehydrogenase level), and imaging confirmed that the lymphoma was confined to the area of the tongue base. The patient was found to have microcytic anemia, and further workup revealed a beta-thalassemia trait.

[FIGURES 2-3 OMITTED]

The patient was treated with a modification of the Stanford regimen (3) plus rituximab for a total of 3 cycles of chemotherapy. Involved-field radiation was planned. (4) The first cycle of chemotherapy involved the administration of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) in addition to both intravenous and intrathecal methotrexate. Despite growth-factor support, the patient developed febrile neutropenia and was admitted. The second cycle of therapy consisted of R-CHOP and intrathecal methotrexate, and the patient again experienced febrile neutropenia despite growth-factor support. The third cycle consisted of R-CHOP in lower doses; the intrathecal methotrexate was omitted. Again, despite the dose reduction and the omission of intrathecal chemotherapy, the patient experienced febrile neutropenia.

Following the third cycle, PET and CT (figure 1, B) of the neck demonstrated that the tumor had resolved completely. Therefore, the decision was made to cancel the involved-field radiation.

At the 2 1/2-year follow-up, the patient exhibited no signs of residual lymphoma.

Discussion

Burkitt's lymphoma is the fastest-dividing lymphoma, with 100% of cells being in a cell cycle at any given time; it has been considered one of the most rapidly growing tumors in humans. (5) The tumor was first described as a neoplasm arising in the jaws of African schoolchildren. (6) Subsequently, a neoplasm of identical histology was identified in the United States. (7)

In 1994, the International Lymphoma Study Group published the revised European-American lymphoma (REAL) classification system for lymphoid neoplasms. (8) In this system, lymphomas were classified according to morphologic appearance, immunophenotype, and genetic features. In 2001, the REAL classification system was updated by the World Health Organization, which classified Burkitt's lymphoma together with Burkitt's leukemia as a mature (peripheral) B cell neoplasm. (9) Previous classification systems had also included "Burkitt's-like lymphoma," but this entity was subsequently considered to be the same as Burkitt's lymphoma. (10)