Solitary plasmacytoma (SP) caused the collapse/destruction of the C2 vertebral body in a 78-year-old male. To provide sufficient posterior stabilization, the patient warranted lateral mass fusion to supplement the bilateral pedicle/screw rod instrumentation. A 78-year-old male presented with neck pain alone. X-rays, computed tomography, and magnetic resonance studies documented C2 vertebral collapse with the complete destruction of both lateral masses. The surgery required a laminectomy (i.e., bilateral lateral mass resection), plus placement of bilateral expandable titanium cages from C1 to C3 to supplement the screw/rod occipitocervical (O-C4) fixation. Adjuvant chemotherapy and radiotherapy were also administered. Two years later, the patient remained neurologically intact and radiographically had no evidence of tumor recurrence. In patients with vertebral plasmacytomas and bilateral lateral mass destruction, posterior occipital-cervical C4 rod/screw fusions may warrant the additional bilateral placement of titanium expandable lateral mass cages from C1 to C3.