Numbness in the jaw, the first symptom of multiple myeloma: a case report

Jawbone involvement and destructive bone lesions in the mandible and maxilla are reported in 30% of patients with multiple myeloma. In general, plasma cell neoplasia rarely occurs in the maxillofacial area, and an incidence of 2.6-3.3 per 100,000 people is reported for solitary plasmacytoma in jawbones. This study aims to present and evaluate a patient with multiple myeloma and the first symptoms in the maxillofacial area.

The patient was a 52 years old woman complaining of painful swelling in the left area of the face that had enlarged during the last month. She was referred to the maxillofacial disease department of the Dental School of Mashhad, Iran in Feb 2022. The patient has had paresthesia in the left area of the face since 6 months ago. In the extra-oral examination, a 4×10 cm mass was observed in the left mandibular angle extending anteriorly toward the sublingual area. The oral mucosa was normal. According to the clinical profile, malignancy was considered a differential diagnosis. Incisional biopsy of the lesion revealed the proliferation of neoplastic plasma cells. The positive result of immunohistochemistry (IHC) staining for CD138, performed on the specimen to confirm plasmacytoma and detection of small primary lytic lesions in the skull and spine confirmed multiple myeloma. The usual symptoms of multiple myeloma, including low back pain, were not observed. The patient underwent chemotherapy under the supervision of a hematologist.

Jawbone involvement is often less mentioned as the first symptom of multiple myeloma; however, compared to the vertebral column or skull lesions, these areas are easily biopsied, providing the possibility of early detection and treatment of multiple myeloma, hence a promising disease prognosis. The concurrence of destructive bone lesions and sensory changes in the maxillofacial area is a red flag. Precise radiographic evaluation and blood tests can help early detect multiple myeloma. Awareness of general dentists about the possibility of blood dyscrasia such as multiple myeloma with such early symptoms in patients can lead to early diagnosis of patients. This report reminds inexperienced clinicians of the special importance of sensory changes in the head and neck.