Giant Cell Reparative Granuloma of Parotid Region Infiltrating the Zygomatic Bone: A case report.

Introduction: Giant cell reparative granuloma is a rare, locally benign tumor with an aggressive behavior resembling malignant neoplasm, originating mainly from the mandible and maxilla; however, it can originate from other sites, such as zygomatic and temporal bones, with a young adult female predilection.

Case Presentation: A 28-year-old female presented to the Department of Otolaryngology and Head and Neck Surgery with a history of a slowly enlarging swelling over the left parotid region for four months. Physical examination revealed a non-erythematous, non-tender, firm mass with no overlying skin changes. Fine needle aspiration cytology of the lesion revealed a multinucleated giant cell-rich tumor and the histopathological examination of an incisional biopsy from the mass confirmed giant cell reparative granuloma. Therefore, a total surgical excision of the mass with curating of the zygomatic and temporal bones was performed with uneventful postoperative course and regular follow ups for one year.

Conclusion: A growing mass in the parotid region in a young adult female with no history of trauma should raise the suspicion of giant cell reparative granuloma. Histopathological examination is the definitive tool for diagnosis, and surgical excision is the treatment modality of choice in such cases.