Primary Gingival Anaplastic Lymphoma Kinase (ALK)-Positive Anaplastic Large Cell Lymphoma in a Young Boy.

Anaplastic large cell lymphoma (ALCL) is a rare non-Hodgkin lymphoma derived from natural killer (NK) or T-cells. It mainly affects lymph nodes, and less frequently, extranodal sites such as the skin, bone, or oral cavity. Lack of awareness of these extranodal manifestations can lead to delayed diagnosis, sometimes with dramatic consequences. Here, we report the case of a young boy referred to our oral pathology consultation with persistent intraoral and cervical swellings that had lasted for three months, despite multiple dental and medical appointments and treatments. He was previously misdiagnosed repeatedly with infectious cellulitis of dental origin. Considering the clinical features, we suspected a malignant process and referred the patient to a pediatric oncohematology department. Anatomopathological analyses revealed an anaplastic lymphoma kinase (ALK)-positive ALCL, and appropriate treatment could be initiated. Extranodal manifestations, particularly oral, are little-known forms of lymphoma, especially in children. In most cases of extranodal ALCL, the first diagnosis considered is a benign tumor, which delays the correct diagnosis. It is therefore essential to raise awareness among practitioners about the detection of extranodal, particularly oral, manifestations of these rare lymphomas.