Background: Giant cell tumors (GCTs) are one of the most common benign bone tumors found in young adults between the ages of 20 and 40. They most frequently occur in the long bones of the legs and arms and are rarely present in the head and neck region. Although they are considered benign, GCTs have the potential to be aggressive and destroy surrounding bone and tissue. As such, understanding its presentation and management is critical. Here, we present the unusual case of a patient presenting with a giant cell tumor of the middle ear and skull base.
Case Presentation: A 19-year-old presented with left-sided facial paralysis and otorrhea. He had a three month history of left ear pain and fullness, which initially resolved with antibiotic ear drops but returned shortly after. CT and MRI showed an extensive soft tissue mass with central necrosis around the left mastoid, displacing the parotid gland and compressing the sigmoid sinus. MRI of the Internal Auditory Canal (IAC) showed a large tumor of the middle ear and mastoid cavity, abutting the course of the facial nerve. Soft tissue biopsy revealed a diagnosis of GCT. Given the size and extent of the tumor, a decision was made to surgically resect the mass utilizing a multidisciplinary team consisting of otolaryngology, neurosurgery, and plastic and reconstructive surgery. An extended parotidectomy with level II neck dissection, sacrifice of the facial nerve, lateral temporal bone resection, and left craniectomy were performed for gross resection of the mass. A cervicofacial flap was used to reconstruct the resulting head and neck defects, allowing for cosmetic defect correction. Currently, the patient is doing well, with excellent wound healing. He has a left facial droop, which is being monitored by both ENT and PRS. MRI is consistent with no active disease.
Discussion: Our case highlights the rare, but significant, occurrence of giant cell tumors in atypical locations such as the middle ear and skull base. The extensive surgical resection involving numerous subspecialties underscores the necessity of collaborative efforts to achieve complete resection of the mass. We highlight the approach taken to resect the tumor, as well as the cosmetic outcome achieved by the surgical team. Long-term follow-up will be necessary to monitor for recurrence and functional outcomes.
Figure 1. Pre-operative image demonstrating the mass protruding anteriorly and posteriorly to the left outer ear.
Figure 2. Coronal (A) and sagittal (B) MRI demonstrating the large invasive Giant Cell Tumor (GCT). The mass is noted to be extending through the middle ear, into the skull base, and displacing the parotid gland.
Figure 3. Intraoperative image demonstrating the depth of tumor invasion and adhesion to the facial nerve, parotid gland, and temporal bone.
Figure 4. Post-operative image demonstrating the cervicofacial flap with cosmetic deformity correction.