Carotid Body Tumor
Carotid Body Tumor Overview
A carotid body tumor is a rare growth located at the carotid bifurcation, where the common carotid artery in your neck splits into the internal and external carotid arteries. This area contains a small cluster cells known as the carotid body, which monitors levels of oxygen and carbon dioxide in your blood to help regulate breathing.
Carotid body tumors, also known as paragangliomas, are generally slow-growing and are usually benign, meaning they are not cancerous and do not spread to other body parts. However, in a small number of cases, they can be malignant. Carotid body tumors can grow large enough to put pressure on nearby structures in the neck, which may cause symptoms such as a lump in the neck that you can feel, difficulty swallowing, hoarseness, or a change in your voice.
The exact cause of carotid body tumors is not well understood. They are thought to be associated with certain genetic factors, especially in cases where multiple family members are affected. They are most commonly diagnosed in adults between 40 and 60 but can occur in people of all ages.
Carotid body tumor diagnosis typically involves physical examination, imaging studies such as CT scans, MRI, or ultrasound, and sometimes angiography to assess the blood supply to the tumor. Carotid body tumors contain many blood vessels and bleed easily, so your doctor may be reluctant to take a biopsy of the tissue.
Treatment options depend on the location and size of the tumor, whether it’s causing symptoms, and its growth rate. Your doctor may be content to monitor small, asymptomatic tumors without immediate treatment. Surgical removal may be recommended for large or symptomatic tumors. In some cases, particularly if the tumor is difficult to remove surgically or if surgery is not a good option for you, radiation therapy may be a viable alternative treatment approach.
Working with a healthcare team experienced in treating carotid body tumors is essential to determine the best treatment plan for your situation.
About the Carotid Artery
The carotid arteries are major blood vessels in your neck that supply blood to your brain, neck, scalp, and face. There are two carotid arteries – one on each side of your neck – and they are divided into two main parts:
Common Carotid Artery
Each common carotid artery starts from different points in your chest and neck. On the right side, the common carotid artery branches off the brachiocephalic artery, which comes directly from the aorta (the main artery leaving the heart). On the left side, the common carotid artery starts directly from the aorta. These arteries then run upward on either side of the neck.
Internal and External Carotid Arteries
At a certain point in the neck, each common carotid artery divides into two branches:
- The External Carotid Artery: This branch supplies oxygen-rich blood to the face, scalp, skull, and parts of the neck. It has several smaller branches that reach different head and neck areas.
- The Internal Carotid Artery: This branch travels upward into the skull and supplies oxygen-rich blood to the brain. It enters the skull through the carotid canal and then divides further to provide blood to a large portion of the brain.
At the point where the common carotid artery splits into the internal and external branches, there is a small, specialized cluster of cells known as the carotid body. The carotid body acts as a chemoreceptor, monitoring oxygen and carbon dioxide levels in the blood to help regulate breathing. The carotid arteries supply the brain with the necessary oxygen and nutrients. Any interruption in this blood flow, such as from a blockage or narrowing (stenosis), can lead to severe conditions like strokes or transient ischemic attacks (TIAs). That’s why the health of your carotid arteries is so vital to your overall brain health.
Carotid Body Tumor Symptoms
Carotid body tumors are rare growths at the carotid bifurcation. While these tumors are usually slow-growing and benign, they can cause symptoms due to their location and the pressure they exert on nearby structures.
Here’s what you might experience if you have a carotid body tumor:
- A Noticeable Lump or Mass: One of the most common signs is feeling a painless, firm lump on one side of your neck, near where the artery divides. This lump may not cause discomfort initially and is often discovered during an examination or imaging study for unrelated reasons.
- Swallowing Difficulties: If the tumor grows large enough, it can press against the esophagus (the tube that connects your mouth and stomach), making swallowing uncomfortable or difficult.
- Voice Changes or Hoarseness: Pressure on the nerves that control your vocal cords, particularly the recurrent laryngeal nerve, can lead to changes in your voice, including hoarseness or a weakened voice.
- Breathing Problems: Sometimes, a large tumor may press against the trachea (windpipe), leading to shortness of breath or difficulty breathing, especially when lying down.
- High Blood Pressure: Rarely, the tumor can interfere with the body’s normal blood pressure regulation, leading to hypertension.
- Pulsatile Tinnitus: Some individuals may experience ringing in the ears that pulses in time with their heartbeat.
Many carotid body tumors are asymptomatic, especially in the early stages, and symptoms typically develop slowly as the tumor grows. If you notice a lump in your neck or experience any of the symptoms mentioned, it’s essential to see a healthcare provider for evaluation. While carotid body tumors are rare, early diagnosis and treatment can help you manage the condition and prevent complications.
Carotid Body Tumor Treatments
Treating a carotid body tumor involves carefully considering the tumor’s size, location, whether it’s benign or malignant, and your overall health. The main treatment options include are described below.
- Observation or Watchful Waiting: If the tumor is small, not causing symptoms, and believed to be benign, your doctor might recommend a watch-and-wait approach. This involves regular monitoring with physical exams and imaging tests, like ultrasound, CT scans, or MRIs, to check if the tumor grows or starts causing problems.
- Surgical Removal: Surgery is the primary treatment for carotid body tumors, especially if they’re causing symptoms or growing. The goal is to remove the tumor altogether. However, the surgery can be complex due to the tumor’s location near critical nerves and blood vessels. The risk of complications, such as nerve damage leading to swallowing difficulties, voice changes, or even stroke, varies depending on the tumor’s size and relationship to these structures. An experienced vascular or head and neck surgeon typically performs this surgery.
- Radiation Therapy: In cases where surgery might be too risky due to the size or position of the tumor, or if your health makes surgery too dangerous, radiation therapy may be an option. Radiation can help to control the growth of the tumor. While it’s generally less preferred than surgery, it can benefit certain patients.
- Embolization: Sometimes used before surgery, embolization is a procedure that helps to reduce the tumor’s blood supply, making surgical removal more manageable and safer. It’s not a standalone treatment but can be part of the treatment plan to minimize blood loss during surgery.
- Management of Malignant Tumors: If the carotid body tumor is malignant (cancerous), treatment may also involve a combination of surgery, radiation therapy, and possibly chemotherapy, depending on the extent of the disease and whether it has spread to other parts of the body.
Your healthcare team will consider several factors before recommending a treatment plan, including the tumor’s characteristics, your overall health, and each option’s potential risks and benefits. It’s important to have open and detailed discussions with your doctors about your treatment choices, what each involves, the possible side effects, and the expected outcomes.
Video: Carotid Body Tumor Surgery
Common Questions about Carotid Body Tumors
How long can you live with a carotid body tumor?
The prognosis and life expectancy for someone with a carotid body tumor generally depend on several factors, including the tumor’s nature (benign versus malignant), size, location, and the presence of any symptoms or complications. The majority of carotid body tumors are benign and, when appropriately managed, usually do not significantly shorten a person’s lifespan. However, there are important considerations:
- Benign Tumors: For benign carotid body tumors, the prognosis after surgical removal is generally excellent. With complete removal, the chance of the tumor coming back is low. The success of surgery and the risk of complications depend on the tumor’s size and the surgeon’s experience. Complications are more common with larger tumors due to their proximity to vital structures in the neck. Still, experienced surgeons can often minimize these risks.
- Malignant Tumors: Malignant carotid body tumors are rare but can be more challenging. They may have a worse prognosis, mainly if they spread to other body parts. Treatment may involve a combination of surgery, radiation therapy, and sometimes chemotherapy. The specific outlook for malignant tumors varies greatly depending on the disease’s extent and treatment’s success.
- Symptoms and Complications: The presence of symptoms or complications related to the tumor, such as difficulty swallowing, changes in voice, or issues related to blood flow, can affect a person’s quality of life. Successful treatment can alleviate these symptoms and significantly improve quality of life.
- Observation: In cases where surgery is not immediately necessary and a watchful waiting approach is taken, regular monitoring is essential to detect changes in the tumor’s size or behavior. This approach requires careful consideration and regular follow-up with your healthcare provider.
It’s important to have a detailed discussion with a healthcare provider specializing in treating carotid body tumors to understand the best approach for your situation, including the potential risks and benefits of treatment options. With appropriate treatment and monitoring, individuals with carotid body tumors often have an average life expectancy, especially if the tumor is benign and successfully treated.
How common are malignant carotid body tumors?
Malignant carotid body tumors are quite rare. Most carotid body tumors are benign, meaning they don’t spread (metastasize) to other body parts. Estimates suggest that the malignancy rate of carotid body tumors varies but is generally low, often cited as being between 5% and 10%. This rate can vary depending on different studies and patient populations.
The determination of malignancy in carotid body tumors is primarily based on the presence of metastasis, either to nearby lymph nodes or more distant sites, since the histological (microscopic) appearance of these tumors may not reliably predict their behavior. Unlike many other cancers, there aren’t specific histological features that clearly distinguish between benign and malignant carotid body tumors; the diagnosis of malignancy is usually made when there is evidence of metastatic spread.
Given their rarity, the management and prognosis of malignant carotid body tumors require a highly individualized approach, often involving a multidisciplinary team. Treatment may include surgical removal of the tumor, possibly combined with radiation therapy or chemotherapy, depending on the scope of the disease and the presence of metastasis.
Despite the potential for malignancy, the overall prognosis for individuals with carotid body tumors, including those with malignant tumors, can be relatively favorable with appropriate treatment and ongoing monitoring.
How fast do carotid body tumors grow?
Carotid body tumors are generally slow-growing. The growth rate can vary widely among individuals. In some cases, the tumor may remain asymptomatic and undetected for years. These tumors grow at a variable rate, and there isn’t a one-size-fits-all answer to how fast they expand. Some studies suggest an average growth rate of around 1 mm to 2.5 mm per year, but this can vary.
The slow-growing nature of these tumors often allows for time to conduct thorough evaluations and make informed decisions about treatment options. However, even though they grow slowly, monitoring is essential. As these tumors enlarge, they can start to press against nearby structures in the neck, potentially leading to symptoms such as difficulty swallowing, voice changes, or other complications related to the compression of nearby nerves or blood vessels.
In cases where a carotid body tumor is detected, healthcare providers typically recommend regular imaging studies, such as ultrasound, CT scans, or MRIs, to monitor the tumor’s size and growth rate over time. This monitoring helps inform decisions about when or if intervention may be necessary based on the tumor’s behavior and any symptoms it may be causing.
For individuals with carotid body tumors, the decision to proceed with treatment, such as surgical removal, is balanced against the potential risks associated with the tumor’s location and the complexity of the surgery. In cases where tumors are small and not causing symptoms, a watchful waiting approach with regular monitoring may be recommended. For larger or symptomatic tumors, surgical removal is often considered to prevent complications despite the slow growth rate of these tumors.
Information and Resources
References
- Srinivasan VM, Labib MA, Rutledge C, Catapano JS, Graffeo CS, Albuquerque FC, Lawton MT. Resection of a Left Carotid Body Tumor With Preoperative Embolization: 2-Dimensional Operative Video. Oper Neurosurg (Hagerstown). 2023 Jul 1;25(1):e25. doi: 10.1227/ons.0000000000000666. Epub 2023 Feb 27. PMID: 36847521.
- Kalani MY, Ducruet AF, Crowley RW, Spetzler RF, McDougall CG, Albuquerque FC. Transfemoral transarterial onyx embolization of carotid body paragangliomas: technical considerations, results, and strategies for complication avoidance. Neurosurgery. 2013 Jan;72(1):9-15; discussion 15. doi: 10.1227/NEU.0b013e3182752d75. PMID: 23147783.