Methods

Table 1: Clinical and demographic characteristics of patients (n=29)

Table 2: Distribution of tumor types according to Shamblin classification

Results

Table 3: Complication in the patients

Discussion

These tumors were first described in 1891 by Marchand, and are more common in women than in men.[5] Results of our study show that the rate of female patients was significantly higher, which is consistent with the studies in the literature. Of the 29 patients 27 (93.1%) were female, while two (6.9%) were male. Although carotid glomus tumors can be seen at all ages, they occur predominantly at the age of 30 and 40 years.[6] The age d istribution of patients who were included in our study varied between 27 and 77, with a mean age of 54.2±3.4 for females and 65 for males.

Signs and symptoms of carotid glomus tumors are detected late at diagnosed due to the slow growing nature of the tumors. They can cause pressure and regional pain to surrounding tissues because of their local growth. Headache is the most common complaint, especially following pressure to the jugular vein. Symptoms such as dysphagia, hoarseness, and feeling of fullness in the ear may be observed due to growth in the neck region, and also cardiac arrhythmia due to vagal nerve compression.[7]

Diagnosis of such tumors is usually made incidentally after US of the neck for a different reason. Definite diagnosis is made by CT or MRI following US. MRI of carotid tumors provides mostly preoperative information on the mode of surgery. McPherson et al.[8] in their study demonstrated the superiority of MRI over CT. The type of tumor is important for preoperative surgical strategy. Shamblin type 1 and type 2 tumors can be easily resected from vascular structures and from surrounding tissues when compared to type 3 tumors. Severe bleeding may be observed with such tumors during removal due to their intense vascular structure. In recent years, attempts to reduce the amount of hemorrhage during surgery have been made in these patients by administering embolization materials under angiography before surgery, to the arterial structures feeding the tumor. In a study by Power et al.,[5] bleeding was reported to be significantly reduced after preoperative embolization; however, no change in cranial nerve injury was observed. In the study conducted by Ilhan et al.[9] no embolization substance was used in any of the patients. No embolization is reported to have been performed due to the risk of cranial embolism in the carotid artery.

Removal of these tumors may result in damage to the neural structures during both dissection and retraction. Especially for the tumors extending under the mandible, there is a risk of temporary paralysis and paresis after the operation due both to stress and compression of the facial nerve from the retraction and dissection performed. Ma et al.[10] reported temporary neurological damage in 14 patients and permanent neurological damage in three patients in their study on 57 patients with a glomus tumor. In our study, no permanent damage was reported in any of our patients during the outpatient clinical follow-ups.

Bradycardia or tachycardia may occur during the operation. Arterial blood pressure from the radial or brachial arteries of the patients should be monitored invasively during dissection of the tumor. Hypertensive crises due to adrenaline and noradrenalin discharge may occur, in paragangliomas cases.[11]

In a study conducted by Amato et al.,[12] 625 patients were studied from data collected from 19 clinics, and a 3% mortality rate was reported due to carotid body tumor. In the same study, cranial nerve injury was reported at a rate of 48% (31% temporary and 17% permanent), whereas a 17% rate of external carotid artery injury was reported.

Postoperative respiratory distress and dysphagia may be due to vagal nerve damage. In a study conducted by Metheetrairut et al.,[13] 38 patients were examined and 5% of the patients were observed to have dysphagia. Three of our patients suffered from dysphagia; however, the condition was observed to have improved during outpatient clinical follow-ups.

In conclusion, surgical excision for carotid body tumors should be considered as the first choice among treatment options. We suggest that it is beneficial to have surgery as soon as the diagnosis is made, because after the growth of the mass excision becomes difficult and the risk of complication also increases. Cranial and peripheral nerve complications which may occur during the operation should be taken into consideration, and removal of the mass should be ensured while paying attention to dissection of the anatomical structures. The mass should be removed as a whole together with the sheath or membrane that surrounds it, otherwise recurrence of the tumor may occur.

Declaration of conflicting interests
The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Funding
The authors received no financial support for the research and/or authorship of this article.

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