Carotid body paraganglioma is a slow growing tumor of head and neck region. It can rarely be malignant in nature which is characterized by distant metastases on anatomical imaging. We share an interesting presentation of a malignant carotid body on F-18 FDG PET/CT in form of liver and skeletal metastases.

UNASSIGNED: Paraganglioma (PG); also known as Glomus Tumor, is a rare neoplastic entity that originates from neural crest cells. It can manifest in different patterns, chiefly benign but others are locally invasive and malignant in behavior. Due to the prevalence of other more common types of neck masses and Paraganglioma\'s exceeding rarity, misdiagnoses can easily take place, and this results in higher patient morbidity and mortality rates. Preoperative diagnosis constitutes a major clinical challenge, especially in patients with a previous surgical history in the neck region like our patient.
METHODS: We are hereby presenting the case of a 56-year-old female with a known history of total thyroidectomy, who presented to our department with a progressively growing painful recurring neck mass two years following her total thyroidectomy. The preoperative diagnostic assessment revealed two unilateral synchronous masses encapsulating the Right Common Carotid Artery and occupying the common carotid bifurcation.
UNASSIGNED: Complete surgical resection of the lesions after isolation from the surrounding anatomical structures was done. Subsequent histopathological and immunohistochemical analyses of the specimens established the diagnosis of a Carotid Body Tumor (CBT).
CONCLUSIONS: CBTs are rare vascular neoplasia, and they possess the potential for malignant transformation. This neoplasia warrants investigation and documentation to establish innovative diagnostic parameters and accomplish timely surgical interventions. To the best of our knowledge, this is the first documented case of a unilateral synchronous malignant Carotid Body Tumor from Syria. Surgery remains the treatment of choice, while radio-/chemotherapy is reserved for non-surgical cases only.

OBJECTIVE: The objective of this study was to investigate population-based epidemiology, survival outcomes, and prognostic factors of malignant carotid body tumors (CBTs).
METHODS: Patients with malignant CBTs who were diagnosed between 1975 and 2018 were screened from nine registries of the Surveillance, Epidemiology, and End Results (SEER) database. Cases that were coded as \"carotid body tumor, malignant\" or malignant tumors with the primary site recorded as \"carotid body\" were screened for inclusion in the study. The incidence of malignant CBT was calculated with SEER∗Stat software. Survival outcomes were analyzed using the Kaplan-Meier method and log-rank tests.
RESULTS: A total of 72 patients with malignant CBT were screened for inclusion in the study, including 41 females (56.9%) and 31 males (43.1%). Based on the SEER program data, the incidence of malignant CBT was found to fluctuate between 0 to 0.02 cases per 100,000 people per year, with a slow but noticeable uptick after 1990. The most commonly affected populations included women and patients between the ages of 35 and 44, which accounted for 59.9% and 27.8% of patients in the study, respectively. During a median follow-up of 82 months, four patients were lost to follow-up, and 28 deaths were identified. Of those, 20 were considered disease-specific deaths. Further analysis found that the 5-year and 10-year overall survival rates were 78.9% and 67.8%, respectively, whereas the 5-year and 10-year disease-specific survival rates were 84.5% and 75.2%, respectively. The Kaplan-Meier method and log-rank tests indicated that age <50 years, sex, race, tumor number, and surgical treatment were unrelated to both overall survival and disease-specific survival.
CONCLUSIONS: A retrospective review of the SEER database found that the incidence of malignant CBT was extremely rare and prone to fluctuation, but that it slowly trended upward over time. Malignant CBT was found to more likely affect females, and it could be diagnosed at any age. The overall prognosis for malignant CBT appeared to be good, with acceptable 5-year and 10-year survival rates. Due to a number of factors complicating malignant CBT surgery, surgical treatment should be considered with caution.