Lymphoma is a cancer originating in the lymphatic system, a network of vessels and tissues that helps the body fight infection. This disease arises from the uncontrolled growth of lymphocytes, a type of white blood cell. When this cancer starts or appears in the mouth, tonsils, tongue, or salivary glands, it is termed oral lymphoma. While cancers like squamous cell carcinoma are more frequent in the oral cavity, lymphoma represents a significant malignancy in this area.
Understanding Oral Lymphoma and Its Types
Oral lymphoma is overwhelmingly classified as Non-Hodgkin Lymphoma (NHL), accounting for the vast majority of cases found in the head and neck region. NHL is broadly categorized based on the type of lymphocyte involved in the cancer’s development. Most oral lymphomas arise from B-cells, the white blood cells responsible for producing antibodies.
A common and aggressive subtype encountered in the mouth is Diffuse Large B-cell Lymphoma (DLBCL). Less frequently, oral lymphomas can involve T-cells, which are lymphocytes that regulate immune response. The most prevalent site for NHL in the head and neck is the Waldeyer’s ring, a collection of lymphoid tissue that includes the tonsils and the tissue at the base of the tongue.
Within the oral cavity itself, the palate, particularly the hard palate, and the gingiva (gums) are the most frequent locations. These lymphomas are considered primary extranodal lymphomas because they begin outside of the main lymph nodes. The specific type of cell involved determines the aggressiveness of the disease and influences the subsequent treatment approach.
Identifying Key Symptoms
Recognizing the signs of oral lymphoma can be challenging because its symptoms often mimic those of more common, non-cancerous oral conditions. The most common presentation is a persistent, painless swelling or mass within the mouth or jaw. This swelling may occur in the tonsil, the roof of the mouth, or the gum tissue and usually grows steadily over time.
Another frequent sign is the development of a non-healing ulcer that does not respond to standard treatments over several weeks. Unlike typical mouth sores, these ulcers may be deep and have raised borders. Patients might also experience generalized discomfort or pain in the mouth or jaw, often mistakenly attributed to dental problems.
As the mass grows, it can lead to functional issues such as difficulty or pain when swallowing, known as dysphagia. If the tumor affects the jawbone, symptoms can include numbness in the face or lower lip, or unusual mobility of the teeth. Systemic symptoms, often called B symptoms, can also occur, including unexplained weight loss, drenching night sweats, and persistent fevers.
Confirmation Through Diagnostic Procedures
A clinician must perform a thorough examination, including a detailed history of the symptoms, when oral lymphoma is suspected. The definitive confirmation of the disease requires a tissue sample, typically obtained through a biopsy. An incisional biopsy removes only a portion of the suspicious mass, while an excisional biopsy removes the entire lesion if it is small enough.
The removed tissue is then examined under a microscope by a pathologist to identify the presence of malignant lymphocytes and determine the specific subtype of lymphoma. Immunohistochemistry, a technique that uses antibodies to detect specific proteins on the cancer cells, is often used to confirm if the cells are B-cell or T-cell in origin.
Once the diagnosis is established, imaging procedures are used to determine the extent of the disease, a process called staging. Computed Tomography (CT) scans, Magnetic Resonance Imaging (MRI), and Positron Emission Tomography (PET) scans are commonly employed. A PET/CT scan, which combines functional and anatomical imaging, is effective at identifying all areas of the body where the cancer may have spread. Blood tests are also performed to assess overall health and check for abnormalities in blood cell counts or organ function.
Standard Treatment Protocols
The treatment strategy for oral lymphoma is highly individualized, depending on the lymphoma subtype, the stage of the disease, and the patient’s overall health. Since most oral lymphomas are Non-Hodgkin Lymphoma, treatment protocols generally align with those for systemic NHL. Chemotherapy is a primary modality, utilizing drugs designed to destroy fast-growing cancer cells throughout the body.
A common and effective regimen for aggressive B-cell lymphomas is R-CHOP, an acronym representing a combination of five drugs. This protocol includes the targeted therapy agent rituximab, a monoclonal antibody that attaches to a protein called CD20 found on the surface of B-cell lymphoma cells. The regimen also includes the chemotherapy drugs cyclophosphamide, doxorubicin (hydroxydaunomycin), and vincristine (Oncovin), along with the steroid prednisone.
Radiation therapy uses high-energy beams to precisely target and kill cancer cells in a localized area. It is frequently employed for early-stage or localized oral lymphomas, either alone or following chemotherapy. The precise delivery of radiation is adapted to minimize damage to surrounding healthy oral and neck tissues.
Targeted therapy and immunotherapy focus on specific molecular targets on the cancer cells or harness the body’s immune system. Rituximab is an example of targeted therapy. For relapsed or refractory disease, high-dose chemotherapy followed by a stem cell transplant may be considered to replace diseased bone marrow with healthy blood-forming cells.