Paresthesia of the left lower lip as a first manifestation of multiple myeloma - A case report

We experienced a case of multiple myeloma in a 62-year-old woman who visited our hospital with a chief complaint of paresthesia in the left lower lip, which was described as numb chin syndrome, as her initial symptom. The radiographic findings showed a large area of osteolytic destruction in the left mandible and multiple punched-out appearances in the skull plate. The MRI demonstrated lesions showing low signal intensity on TIWI, and medium intensity on T2WI. The scintigram of the whole-body revealed a positive image in the left mandible and multiple ribs. On clinical laboratory examination, the data revealed higher total protein, γ-globulin, IgG, CRP, and SAA, and lower albumin than normal. Pathologic findings revealed a neoplastic mass showing diffuse proliferation of atypical plasmacytoid cells with little stroma. Serum immunoelectrophoresis disclosed M-protein, indicating abnormal immunogloblin synthesized by tumor cells. The final diagnosis was multiple myeloma. Although the initial manifestation of multiple myeloma rarely appears in the oral/jaw area, this disease should be borne in mind as a differential diagnosis when considering a patient whose chief complaint is paresthesia, so-called numb chin syndrome (NCS), and careful examination of the disease including radiographic imagings should be undertaken.