Recurrent Anterior Skull Base Plasmocytoma

CASE HISTORY

A 53-year-old man was referred for treatment of a mass that invaded the posterior nasal cavity, ethmoid sinuses, both posterior orbits, and anterior skull base. Eighteen years earlier, he had been diagnosed with a solitary plasmacytoma of the paranasal sinuses. Despite treatment with 4500 cGy radiation therapy, the tumor continued to grow and was subtotally resected 3 years later through a transfacial approach. Two years before his current referral, he underwent a second operation for a massive recurrent tumor. On that occasion, the highly vascularized tumor was completely removed anterolaterally through a subcranial approach. The patient elected not to have the pericarotid and perichiasmatic extensions of the tumor removed to spare these vital structures. The anterior skull base was reconstructed with the use of fascia lata, biological glue, and titanium miniplates. After surgery, the patient returned to his native country with the recommendation to undergo a complementary course of radiation therapy and chemotherapy.

The patient experienced intermittent epistaxis and nasal obstruction for 3 months before his current referral. He had received no radiological or chemotherapeutic intervention during the intervening 2 years. On examination he appeared well. His speech and gait were normal, and he suffered no visual disturbances. Transnasal endoscopic examination showed that the anterior cavity was clean. A reddish mass obstructed the posterior nasal cavity and choana. Mirror laryngoscopy revealed normal vocal fold function and no suspicious lesions of the oropharynx, hypopharynx, or larynx. The oral cavity and tongue were normal. The neck was without adenopathy. Cranial nerves function was intact. The remainder of the physical examination revealed no musculoskeletal or cardiovascular abnormalities.

His erythrocyte sedimentation rate was 50 mm/h and his blood count was normal. Electrolytic, calcium, glucose, albumin, and liver functions were normal. Serum electrophoresis was normal, with serum globulin of 22 g/L and no monoclonal peak. Urinalysis was normal, and a test for Bence-Jones protein was negative. Pathological examination of the bone marrow aspirate showed a normal number of mature plasma cells with no evidence for monoclonal heavy or light chains.

Computed tomography (CT) and magnetic resonance imaging (MRI) of the skull base, paranasal sinuses, and orbits showed a 3- × 4-cm vascularized tumor involving the ethmoid cells and sphenoid sinus, eroding both orbits and invading the anterior cranial fossa. Posteriorly, the tumor impinged on both the carotid arteries and optic nerves (Fig. [1]).

Histopathological examination of the previous biopsy showed diffuse sheets of immature-appearing plasma cells (Fig. [2]). Immunohistochemical staining confirmed the diagnosis of plasmacytoma.