From the Guidelines
A carotid body tumor, also known as a paraganglioma, is a rare, usually benign growth that develops at the carotid bifurcation in the neck, where the common carotid artery divides into internal and external branches, arising from specialized chemoreceptor cells that monitor blood oxygen levels 1.
Key Characteristics
- These tumors are typically slow-growing and non-cancerous (about 90%), though a small percentage can be malignant 1.
- Patients often present with a painless, pulsatile mass in the neck that may cause symptoms like difficulty swallowing, voice changes, or dizziness as the tumor enlarges and compresses surrounding structures.
- Diagnosis involves imaging studies such as CT scans, MRI, or specialized angiography to visualize the tumor's blood supply 1.
Treatment Considerations
- Treatment generally consists of surgical removal, which requires careful planning due to the tumor's proximity to critical blood vessels and nerves 1.
- For patients who are poor surgical candidates, radiation therapy may be considered, with long-term tumor control noted in 94.5% of IMRT patients and 93.8% of surgical patients 1.
- The primary goal of treatment is to minimize morbidity and mortality, while preserving quality of life, with careful consideration of the patient's life expectancy, tumor behavior, and baseline neurological status 1.
Management Approach
- An individualized approach is recommended, taking into account the patient's specific circumstances and the expertise of a multidisciplinary team 1.
- Preoperative angiography with embolization is recommended for large or locally invasive tumors, and balloon occlusion testing is recommended for lesions that encase the internal carotid artery 1.
- The decision to operate should be made cautiously, considering the risk of cranial neuropathies and the potential for significant complications, with particular attention paid to the patient's swallowing function and pulmonary reserve 1.
From the Research
Definition and Characteristics of Carotid Body Tumors
- Carotid body tumors, also known as carotid paragangliomas, are rare neuroendocrine neoplasms derived from neural crest cells 2.
- They are benign in most cases, but malignant forms can occur, with approximately 4.2% of tumors being malignant 3.
- These tumors arise from the paraganglia located within the adventitia of the medial aspect of the carotid bifurcation 2.
- Carotid body tumors can cause localized pain, dysphagia, hiccups, hoarseness, and hypersensitive carotid body syndrome 4.
Diagnosis and Treatment
- Diagnosis is typically made using imaging studies such as CT scans, MRI, and duplex scans, with duplex scan being the best investigation for diagnosis 3.
- Surgery is the treatment of choice, with surgical resection being the most widely-used technique, sometimes accompanied by preoperative endovascular embolization 4.
- The aim of surgical treatment is to completely remove the tumor, which can be challenging due to the complex anatomical location and potential neurovascular complications 2.
- Careful subadventitial dissection and accurate excision are crucial to separate the tumor from the carotid bifurcation without causing traumatic lesions 5.
Complications and Outcomes
- Postoperative complications can include stroke, cranial nerve injury, and mortality, with an overall complication rate of 35% and mortality rate of 1% 3.
- Cranial nerve palsy can occur in up to 49% of cases, while stroke rates vary from 0 to 8% 4.
- Preoperative embolization has been used to decrease tumor volume and intraoperative blood loss, but its benefits are still debated, with some studies finding no significant advantages 6.