From the subset of malignancies affecting the head and neck region, lymphomas are the second most frequent after carcinomas. From those lymphomas, 80% to 90% are Non-Hodgkin lymphomas and about 4% represent Hodgkin lymphoma (HL) [1
]. The incidence of HL is estimated to be 7400 new cases per year in the United States, accounting for approximately 30% of all lymphomas [3
]. As well known, most of the HL involves the lymph nodes. However, under some circumstances, those tumors arise from tissues other than the lymph nodes. Trying to define certain anatomical area, the term Waldeyer ring is used to include the lymphoid tissues of the faucial tonsils, nasopharynx, base of tongue, and oropharynx and therefore is considered an extranodal but not an extralymphatic site [4
]. HL cases arising from this tissue, although uncommon, are being well characterized [5
]. Therefore, the term extranodal, extralymphatic lymphoma has been used to describe the uncommon form of lymphoid malignancy, in which there is neoplastic proliferation at sites other than the expected native lymph nodes and lymphoid tissue, respectively. Due to the difficulty in case definition, the frequency of this type of variation is not well established, nevertheless when sites rich in primary lymphoid tissue such as Waldeyer's ring and spleen are considered extranodal, extranodal lymphomas would represent 25–50% of all non-Hodgkin lymphomas and only 2–5% of classical Hodgkin lymphomas [6
]. In the case herein reported, the lymphoma was localized in the mandible with extension to the buccal mucosa; both considered outside the boundaries of the Waldeyer's ring.
Extranodal, extralymphatic lymphomas from the bone are uncommon, comprising only 8% of primary malignant bone tumors and they are mainly diffuse B-cell type non-Hodgkin lymphomas [7
]. This is probably the third case reported of a primary extranodal and extralymphatic oral Hodgkin lymphoma of the mandible [8
]. There is no information on the progression of the first case [8
], but the second case relapsed 17 months after diagnosis and involved field radiotherapy of the pleura, spleen, liver, and para-aortic and inguinal lymph nodes, dying 6 months later after five cycles of chemotherapy with MOPP regimen (nitrogen, mustard, vincristine, procarbazine, and prednisone) [9
]. Since the applicability of International Prognostic Score is restricted to advanced stage disease [10
], a recent study showed that the absence of tumor associated macrophages represented by the marker CD68, such in this case, is strongly correlated with 100% ten-year disease specific survival [11
]. Our case was in complete remission 3 months into therapy. We are describing the course of this rare HL presentation and the favorable early response to standard chemotherapy. This displayed the wide clinical spectrum that this type of tumor may encompass. Remarkable still little is known about the survival, prognosis, and effectiveness of the chemotherapy for this rare variant.