Solitary bone plasmacytoma mimicking a lesion of odontogenic origin: A case report

Introduction and importance: Solitary bone plasmacytoma (SBP) is an early-stage plasma cell malignancy. It is an extremely rare condition and its diagnosis may not be straightforward. This report presents a case of maxillary SBP. Case presentation: A 48 -year old man sought care for persistent swelling and pain in the periapical region of the left maxillary molars. He had been diagnosed with "apical periodontitis" and root canal treatment of teeth #26 and #27 was ineffective. Extra-oral examination revealed swelling at the left maxilla. Intraoral examination revealed a hard, non-fluctuant swollen region in the buccal alveolar mucosa adjacent to the apices of teeth #25-27. Cone-beam computed tomography revealed extensive bone destruction in the left maxilla. The patient underwent partial maxillary resection and radical maxillary sinusotomy. Further testing (positron emission CT scan, histopathological and immunohistochemical examination) confirmed the diagnosis of SBP. The patient had a recurrence two years later, which was managed with left subtotal maxillectomy and radiotherapy. There was no evidence of recurrence during 20 months of follow-up. Discussion: SBP may mimic an odontogenic lesion when found in the jaw bone. To confirm the diagnosis, routine blood test, complete body skeletal survey, metastatic investigations and histopathology should be performed. Radiotherapy is the primary treatment. Conclusion: SBP may occur in the maxilla mimicking an odontogenic lesion. Surgery may be part of the diagnostic procedure and an adjunct to definitive radiation. Radiotherapy is the primary treatment.