A Systematic Review and Meta-Analysis of the Presentation and Surgical Management of Patients With Carotid Body Tumours

Carotid body tumors-epidemiology and surgical resection

Carotid body tumor originates from paraganglion cells of the carotid body and is a hypervascular tumor with multiple feeding arteries and uniquely located at the carotid bifurcation. Recently, it has been revealed that various types of gene alterations exist mainly in the succinate dehydrogenase (SDH) gene family. Although resection is a radical therapy for this tumor, complete resection is challenging. On the other hand, radiotherapy for carotid body tumors is insufficient as a radical therapy concerning the response rate. Here, we reviewed articles reporting carotid body tumor treatment and surgical resection focusing on choice of treatment, surgical difficulties, and preoperative embolization of feeding arteries. The effectiveness of preoperative embolization remains controversial due to the varied situations performing surgical resection among the institutions.

The Relationship Between Preoperative Neutrophil-Lymphocyte Ratio and Postoperative Length of Stay in Carotid Body Tumor Resection

Carotid body tumor (CBT) resection is a complex surgical procedure often resulting in extended postoperative length of stay (PLOS) due to potential nerve injuries, arterial damage, and wound complications. The neutrophil-to-lymphocyte ratio (NLR) is a known marker of systemic inflammation and has been associated with adverse outcomes in various surgical settings. However, the relationship between preoperative NLR and PLOS in CBT patients has not been explored. This study aims to investigate the association between preoperative NLR and PLOS in CBT resections, particularly examining whether elevated NLR correlates with longer hospital stays and potentially hinders recovery. In this retrospective cohort study, we analyzed data from 231 CBT patients who underwent resection at Changhai Hospital, Shanghai, between 2008 and 2020. Patients were grouped based on their PLOS (short, medium, and long stays), and NLR was calculated from peripheral blood samples taken preoperatively. Univariate and multivariate regression models adjusted for sociodemographic and operative factors, including Shamblin classification, were used to examine the relationship between NLR and PLOS. Elevated preoperative NLR has been found to be significantly correlated with prolonged PLOS, with each incremental increase in NLR corresponding to an approximate extension of 0.12 days in PLOS after adjusting for confounding factors. Stratified analysis revealed that this association was most pronounced in patients with Shamblin II tumors, likely due to the moderate tumor size and adhesion in these cases, which necessitates more extensive dissection and increases vulnerability to nerve injury. Elevated preoperative NLR may serve as a predictor of prolonged recovery in CBT resections, particularly for Shamblin II cases. This finding highlights the potential utility of NLR in preoperative assessment and patient management to optimize surgical timing and reduce hospital stays. Further research with larger cohorts is needed to confirm the predictive value of NLR and explore its clinical application in surgical planning for CBT patients.

Bilateral carotid body tumor management: tips, tricks, strategies, and problems

PURPOSE OF REVIEW

Carotid body tumors (CBTs) are rare neuroendocrine tumors with an annual incidence of 1 : 30 000. Bilateral carotid body tumors (BCBTs) account for 3-5% of all CBTs and are more frequently linked to familial syndromes and potential malignancy. BCBT management is still not universally standardized and depends on multiple factors, including patient's age, risk of malignancy, location, growth rate, size, and related Shamblin and Mehanna classifications.

RECENT FINDINGS

Options of treatment include active surveillance, external beam radiation, and surgery. Surgery is the first-choice treatment, but it may not always be performed especially in elderly patients. Simultaneous BCBT resection is not suggested due to high intra-operative and postoperative risks. The decision to operate on the larger or smaller tumor first is still debated. Whenever feasible, treatment of the larger tumor first to reduce the tumor burden should be preferred but with higher risks of neurovascular injury. Conversely, starting with the smaller tumor first offers a lower risk at initial surgery but may complicate the management of the larger tumor later.

SUMMARY

Surgery for BCBTs, whenever feasible, remains the most indicated treatment but poses a significant risk of neurovascular complications. Resection of the larger, often more symptomatic, and potentially problematic or malignant tumor, reduces the overall disease burden and mitigates risks of rapid progression but involves a higher immediate complication hazard. Multidisciplinary evaluation is essential for balancing surgical risks and long-term outcomes, prioritizing neurovascular preservation and reducing morbidity.

Pheochromocytomas and Paragangliomas-Current Management

Pheochromocytomas and paragangliomas (PPGLs) are infrequent neuroendocrine hypervascular neoplasms arising within different sites of the paraganglion system. They are divided into sympathetic (including pheochromocytomas and extraadrenal paragangliomas) and parasympathetic extraadrenal tumors. These tumors are usually not malignant and grow slowly; about 90% of them are found in the adrenal paraganglia (pheochromocytomas). Extraadrenal tumors are most frequently located in the abdominal cavity (85%), followed by the thoracic cavity (12%), and head and neck (3%). About 25% of PPGLs are related to germline mutations, which are risk factors for multifocal and metastatic disease. In PPGL diagnostics, laboratory, biochemical, and imaging (anatomical and functional) examinations are used. Surgery is the standard management choice for locoregional disease. For patients who are not candidates for surgery and who have stable, not-growing, or slow-growing tumors, active observation or other less invasive techniques (i.e., stereotactic surgery, hypofractionated stereotactic radiotherapy) are considered. In metastatic disease, systemic therapies (tyrosine kinase inhibitors [TKIs], mTORC1 inhibitor everolimus, immunotherapy, cold somatostatin analogs [biotherapy], and radioligand therapy) are used. The prognosis for PPGLs is quite good, and the 5-year survival rate is >90%. The goal of this paper is to review knowledge on the etiopathogenesis, current diagnostics, and therapy for PPGL patients. Our paper is particularly focused on the current management of PPGLs.

Staged surgery for the treatment of carotid aneurysm

Extracranial carotid artery aneurysm (ECAA) is a relatively rare vascular lesion of the neck, and is usually found incidentally and is usually asymptomatic. Surgery is currently the first choice for symptomatic or growing ECAA, including open resection of the entire aneurysm, with or without arterial replacement and insertion of grafts. Ischemic stroke is the most serious complication after resection of ECAA. The preoperative Matas test facilitates the collateral circulation through the circle of Willis， which allows the brain to adapt to the hypoxic situation and effectively reduces ischemic stroke. We report a case of a young patient who underwent a staged surgery to treat it (the first stage was prophylactic carotid artery blockade, so called open Matas test), and achieved good results.

Percutaneous preoperative embolization with onyx in the management of a carotid body tumor: A case report

Carotid body tumors (CBTs) are rare, hypervascular neuroendocrine neoplasms that can lead to significant complications during surgical resection due to the high risk of bleeding. We present the case of a 64-year-old male with a palpable neck mass on the left side, diagnosed as a CBT through imaging studies. Given the tumor's increasing size and rich vascularization, percutaneous preoperative embolization with Onyx under ultrasound and angiographic guide, was performed to minimize intraoperative complications. Forty-eight hours later, the tumor was surgically resected with minimal blood loss and no injury to cranial nerves or the carotid bifurcation.

Debulking surgery prior to stereotactic radiotherapy for head and neck paragangliomas

Background

Surgery has been used as standard treatment for head and neck paragangliomas. Stereotactic radiotherapy (SRT) has also been increasingly used for this disease. The results for combined modality are not well described. This analysis aims to describe the results for combined modality of debulking surgery and SRT for head and neck paragangliomas (HNP).

Materials and and methods

Retrospective cohort of patients treated in a large university hospital between 2008 and 2023.

Results

Fifty-one patients had their charts reviewed. Mean age was 56.3 years. Most were female (82.3%). Most lesions arose from the skull-base (84.3%) and not the inner ear. Most lesions were larger than 3 cm (51.0%) and mean lesion size was 4.4 cm. 36 (70.6%) were treated with radiotherapy alone while 15 (29.4%) were treated with combined modality treatment. Median follow-up was 42.5 months (7.1-112.8 months). There were no reported deaths nor disease progression. Debulking surgery did not impact response rate for SRT (52.8% vs. 47.2% for SRT alone and debulking surgery, respectively, p = 0.971). There was no impact on new neurological deficits after SRT (25.0 vs. 13.3%, respectively, p = 0.356).

Conclusion

Debulking surgery did not improve response rate for SRT. In our sample, it also did not impact new neurological deficits for SRT. Prospective data regarding HNP treatment is needed.

Clinical management and outcome of head and neck paragangliomas (HNPGLs): A single centre retrospective study

CONTEXT

Head and neck paragangliomas (HNPGLs) are rare, usually benign, slow-growing tumours arising from neural crest-derived tissue. Definitive management pathways for HNPGLs have yet to be clearly defined.

OBJECTIVE

To review our experience of the clinical features and management of these tumours and to analyse outcomes of different treatment modalities.

METHODS

Demographic and clinical data were obtained from The Northern Ireland Electronic Care Record (NIECR) as well from a prospectively maintained HNPGL database between January 2011 through December 2023.

RESULTS

There were 87 patients; 50 females: 37 males with a mean age of 52.3 ± 14.2 years old (range 17-91 years old). 58.6% (n = 51) of patients had carotid body tumours, 25.2% (n = 22) glomus vagal tumours, 6.8% (n = 6) tumours in the middle ear, 2.2% (n = 2) in the parapharyngeal space and 1.1% (n = 1) in the sphenoid sinus. 5.7% (n = 5) of patients had multifocal disease. The mean tumour size at presentation was 3.2 ± 1.4 cm (range 0.5-6.9 cm). Pathogenic SDHD mutations were identified in 41.3% (n = 36), SDHB in 12.6% (n = 11), SDHC in 2.2% (n = 2) and SDHA in 1.1% (n = 1) of the patients. Overall treatment modalities included surgery alone in 51.7% (n = 45) of patients, radiotherapy in 14.9% (n = 13), observation in 28.7% (n = 25), and somatostatin analogue therapy with octreotide in 4.5% (n = 4) of patients. Factors associated with a significantly higher risk of recurrence included age over 60 years (p = .04), tumour size exceeding 2 cm (p = .03), positive SDHx variants (p = .01), and vagal and jugular tumours (p = .04).

CONCLUSION

The majority of our patients underwent initial surgical intervention and achieved disease stability. Our results suggest that carefully selected asymptomatic or medically unfit patients can be safely observed provided lifelong surveillance is maintained. We advocate for the establishment of a UK and Ireland national HNPGL registry, to delineate optimal management strategies for these rare tumours and improve long term outcomes.

Prevalence, characteristics, evaluation, and management of carotid body tumors: Systematic analysis based on available evidence

OBJECTIVE

Although carotid body tumors (CBTs) are rare, they attract particular attention because of their propensity for malignant transformation and the high surgical risk. Because data are scarce and as it is difficult to achieve a large sample size, no study has yet comprehensively analyzed the characteristics, management, or operative complications of CBTs. Therefore, we collected and analyzed all currently available information on CBTs and used the pooled data to derive quantitative information on disease characteristics and management.

METHODS

We systematically searched PubMed, Embase, the Cochrane Library, and the Web of Science up to December 1, 2022, for studies that investigated the characteristics and management of CBTs. The primary objective was to identify the prevalence of the various characteristics and the incidence of complications. The secondary objective was to compare patients who underwent preoperative embolization (PE) and those who did not (non-PE), as well as to compare patients with different Shamblin grades and those with and without succinate dehydrogenase (SDH) mutations in terms of CBT characteristics and complications. Two reviewers selected studies for inclusion and independently extracted data. All statistical analyses were performed using the standard statistical procedures of Review Manager 5.2 and Stata 12.0.

RESULTS

A total of 155 studies with 9291 patients and 9862 tumors were identified. The pooled results indicated that the median age of patients with CBT was 45.72 years, and 65% were female. The proportion of patients with bilateral lesions was 13%. In addition, 16% of patients had relevant family histories, and the proportion of those with SDH gene mutations was 36%. Sixteen percent of patients experienced multiple paragangliomas, and 12% of CBTs had catecholamine function. The incidence of cranial nerve injury (CNI) was 27%, and 14% of patients suffered from permanent CNI. The incidence rates of operative mortality and stroke were both 1%, and 4% of patients developed transient ischemic attacks. Of all CBTs, 6% were malignant or associated with metastases or recurrences. The most common metastatic locations were the lymph nodes (3%) and bone (3%), followed by the lungs (2%). Compared with non-PE, PE reduced the estimated blood loss (standardized mean difference, -0.95; 95% confidence interval [CI], -1.70 to -0.20) and the operation time (standardized mean difference, -0.56; 95% CI, -1.03 to -0.09), but it increased the incidence of stroke (odds ratio, 2.44; 95% CI, 1.04-5.73). Higher Shamblin grade tumors were associated with more operative complications. Patients who were SDH gene mutation-positive were more likely to have a relevant family history and had more symptoms.

CONCLUSIONS

CBT was most common in middle-aged females, and early surgical resection was feasible; there was a low incidence of serious operative complications. Routine PE is not recommended because this may increase the incidence of stroke, although PE somewhat reduced the estimated blood loss and operation time. Higher Shamblin grade tumors increased the incidence of operative complications. Patients who were SDH gene mutation-positive had the most relevant family histories and symptoms.

Fifteen Years of Experience with Surgical Management of Bilateral Non-familial Carotid Body Tumors

BACKGROUND

Bilateral carotid body tumors (CBTs) clinical manifestation is infrequent. We conducted this work to describe our experience in the surgical treatment of bilateral CBT and to analyze our results.

METHODS

A retrospective, observational study. We analyzed the totality of bilateral CBT resections that had been performed in our institution from January 2008 to September 2023. Data was obtained from medical records and anonymized, ethics approval was obtained from our institution committee. As the number of observations was less than those required by the central limit theorem our sample was considered nonparametric. Statistical analysis was performed on Stata 17.

RESULTS

We evaluated 16 patients with a total of 32 CBT; surgical resection was performed in 28 cases (87.50%). Median age of the patients was 60 years (interquartile range [IQR] 46-64). Regarding the Shamblin classification, 9 CBTs (32.14%) were classified as Shamblin I, 11 (39.29%) as Shamblin II, and 8 (28.57%) as Shamblin III. The median Distance to the Base of the Skull (DTBOS) was 3.5 cm (IQR 2.7-5.1), and the median tumor volume was 11.25 cc (IQR 3.4-18.7). The median bleeding volume was 300 ml (IQR 200-500), and the median surgical time was 190 min (IQR 145-240). All surgeries were performed using the Retrocarotid Dissection technique. We documented 9 (32.14%) cases of nerve injuries, all of which were transitory. In the median regression a statistically significant association was found between DTBOS, Shamblin classification and tumor volume with intraoperative bleeding and length of stay.

CONCLUSIONS

Surgical treatment remains safe and should be considered the gold standard for accurate histologic diagnosis. DTBOS and tumor volume, in addition to Shamblin classification, must be considered in preoperative planning to predict bleeding and hospital stay.

Surgical and Histopathological Results in Carotid Body Tumors

OBJECTIVE

 The possible relationships between the histopathological findings of carotid body tumors and age, gender, tumor diameter, and Shamblin classification were investigated. In addition, preoperative embolization status, development of neurological complications, need for vascular reconstruction, hemoglobin change, and discharge time were examined and the effects of these variables on each other were analyzed.

METHODS

 Between 2008 and 2022, 46 cases who underwent carotid body tumor excision were examined retrospectively. The cases were followed for an average of 81 months postoperatively. Histopathological materials were reexamined and the effect of categorical variables was analyzed.

RESULTS

 Mean tumor diameter was 3.55 ± 1.26 cm, mean discharge time was 3.91 ± 2.37 days, and mean hemoglobin change was 1.86 ± 1.25. Neurological complications developed in 13% of cases. The amount of hemoglobin change was significantly (p = 0.003) higher in those who developed neurological complications, whereas the tumor diameter and discharge time were found to be insignificantly higher. Surgical complications requiring vascular repair occurred in 10.8% of cases. Tumor diameter (p = 0.017) and hemoglobin change (p = 0.046) were significantly higher in these patients. There were significant correlations between higher Shamblin classification and tumor diameter, discharge time, postoperative hemoglobin value, and number of surgical and neurological complications. No significant difference was found between Ki-67, capsular invasion, mitosis, pleomorphism, prominent nucleoli, mean island diameter, and tendency of islands to merge with categorical variables.

CONCLUSION

 As the tumor diameter increases, the operation becomes more difficult and the postoperative complication rate increases. We think that subadventitial and capsular removal of the tumor is effective in preventing recurrence. To reach a histopathological conclusion, a larger series of studies including tumors with high Ki-67 and mitosis rates, large size, and one or more of the criteria for necrosis are needed.

Current management of carotid body tumors

Carotid body tumors (CBTs) are neoplasms that occur at the bifurcation of the carotid artery and are pathologically classified as paragangliomas. In the 4th edition of the WHO classification, paragangliomas are categorized as neoplasms with malignant potential. Clinically, about 5% of CBTs present with malignant features such as metastasis. Currently, it is challenging to distinguish between tumors with benign courses and those that present malignantly. Recent advances in genetic testing have elucidated the genetic characteristics of paragangliomas, including carotid body tumors. Over 20 genes have been identified as being involved in tumor development. Particularly in head and neck paragangliomas, abnormalities in genes related to succinate dehydrogenase are frequently observed. Research is ongoing to understand the mechanisms by which these genes contribute to tumor development. The definitive treatment for CBTs is surgical resection. These tumors are prone to bleeding and often adhere firmly to the carotid artery, making intraoperative bleeding control challenging. The risk of lower cranial nerve paralysis is relatively high, and there is a risk of stroke because of manipulation of the carotid artery. Preoperative evaluation with angiography is essential, and a multi-disciplinary surgical team approach is necessary. In cases where the tumor is difficult to resect or has metastasized, radiation therapy or chemotherapy are employed. Clinical trials involving targeted molecular therapies and radiopharmaceuticals have recently been conducted, with some applied clinically. The development of various new treatments is anticipated, providing hope for therapeutic options in refractory cases.

Retrocarotid dissection technique compared to the caudocranial approach for the surgical treatment of carotid body tumors: A 15-year experience

INTRODUCTION

Carotid body tumors are rare neoplasms with malignant potential. We aim to follow up on our initial experience published in 2015 and compare the occurrence of complications and postoperative outcomes with the use of retrocarotid dissection (RCD) against the standard caudocranial (SCCD) technique.

METHODS

This was an observational, case-control study in which we analyzed all of the carotid body tumor resections performed from 1986 to 2022. Parametric and nonparametric tests were used accordingly. Statistical analysis was performed on Stata 17.

RESULTS

A total of 181 surgical procedures were included, mean age was 56 years (± 13.63), and 168 (93%) were performed in women. The mean medio-lateral diameter was larger in the RCD group (2.85 ± 1.57 cm vs 1.93 ±1.85 cm; p = 0.002) and presurgical embolization was more frequently performed in the SCCD group (27.5% vs 0.7%; p < 0.001). A total of 40 (22.09%) resections were performed using the SCCD technique. In contrast, in 141 (77.91%) procedures the RCD technique was used. The mean surgical time in the RCD group was lower (197.37 ± 70.56 min vs 232 ± 98.34 min; p = 0.01). No statistically significant difference was found between SCCD and RCD in terms of vascular lesions (n = 20 [11.04%], 15% vs 9%, respectively; p = 0.36), transient or permanent nerve injuries (25% vs 33%, respectively; p = 0.31), or mean intraoperative bleeding (SCCD: 689.95 ± 680.05 mL vs RCD: 619.64 ± 837.94 mL; p > 0.05).

CONCLUSIONS

RCD appears to be a safe and equivalent alternative to the standard caudocranial approach in terms of intraoperative bleeding or vascular lesions, with a sustained, significant decrease in surgical time.

Paragangliomas of the Head and Neck: A Review of the Latest Diagnostic and Treatment Methods

Background and objectives: Paragangliomas of the head and neck are rare, slow-growing neuroendocrine tumors, benign in their vast majority, but with a possibility of developing distant metastases. They show great inheritable character, and their behavior has proven to be unpredictable; therefore, they are considered malignant. Material and methods: This article aims to offer a more comprehensive presentation of the pathogenesis, epidemiology, diagnostic methods, imaging development, and treatment guidelines. We tried to bring together all the necessary data that, in our opinion, a head and neck practitioner should know when managing this type of tumor. Our main focus is on the most recent studies, with the purpose of a homogenous presentation of all current guidelines and approaches to this pathology. Results: Paragangliomas of the head and neck are still a disputed topic. One of the main reasons for that is their low incidence of 0.3 to 1 per 100,000 every year. The most frequent locations are the carotid body, the temporal bone, the jugular and mastoid foramen, and the vagal nerve. Their clinical presentation usually involves a painless lateral mass associated with symptoms such as hoarseness, hearing loss, tinnitus, and cranial nerve deficits. Up to 40% of them are inherited, mostly linked with mutations of succinate dehydrogenase complex. Imaging evaluation consists of CT and MRI, and new functional explorations such as 18F-FDA and 18F-FDG PET/CT, 18F-DOPA PET, 123I-MIBG, and 68Ga-DOTATE PET/CT. Measuring the catecholamine levels in the plasma and urine is mandatory, even though paragangliomas of the head and neck rarely display secretory behavior. Treatment mainly consists of surgery, with different approaches and techniques, but conservative management methods such as wait and scan, radiotherapy, proton therapy, and chemotherapy have proven their efficiency. The therapeutical decision lacks consensus, and current studies tend to recommend an individualized approach. Guidelines regarding long-term follow-up are still a matter of debate.

Clinical outcomes and challenges of surgical extirpation for carotid body paraganglioma in South Korea: a single-center retrospective study

BACKGROUND

Carotid body paraganglioma (CBP) is a rare, highly vascularized, and slow-growing neuroendocrine tumor. Surgical resection is the definitive treatment for CBP, however, it remains challenging due to the tumor's proximity to critical blood vessels and cervical cranial nerves. This study aimed to document the characteristics of CBP and examine the clinical outcomes of patients following surgical extirpation of CBP.

METHODS

This is a single-center retrospective review analyzed patients who underwent CBP extirpation. We examined the patient demographics, preoperative clinical features, tumor characteristics, levels of catecholamines and their metabolites in the serum and urine. Surgeries were performed by one vascular surgeon with follow-ups at 1,3,6 months and yearly thereafter. Logistic regression analysis was conducted to identify risk factors associated with the occurrence of either permanent or temporary cervival cranial nerve palsy (CNP).

RESULTS

From September 2020 to February 2023, this study examined 21 cases of CBP removal surgeries that were carried out in 19 patients. The mean age of the patients was 38.9 ± 10.9 years and the percentage of males was 57.1% (n = 12). The most common preoperative clinical feature was painless neck mass (n = 12; 57.1%). Complete resection was achieved in 20 cases; excluding one case with pathologically proven sclerosing paraganglioma. Vascular procedures were performed in four cases (ECA resection, n = 2; primary repair of ICA tear without carotid shunting, n = 1; and ICA patch angioplasty with carotid shunting, n = 1). Temporary cranial neurologic complications, specifically aspiration and hoarseness occurred in four (19.0%), and three (14.3%) cases, respectively. Hoarseness associated with permanent CNP persisted for more than 6 months in two cases (9.5%). No recurrence or mortality was observed during the follow-up period.

CONCLUSIONS

Surgical resection is the primay treatment approach for CBP; however, it poses risks of vascular or cervical CNP. The intraoperative estimated blood loss was the only identified risk factor for CNP.

Physiological and clinical impact in the carotid baroreceptor function following the surgical management of bilateral carotid body tumors

OBJECTIVE

The bilateral presentation of Carotid Body Tumors (CBT) is rare; the surgical resection of these masses remains the mainstay management due to the malignant potential. We aim to describe, classify, and quantify baroreceptor failure (BRF) after the surgical management of patients with bilateral CBT to better understand the clinical consequences.

METHODS

Retrospective review of patients that underwent bilateral CBT resection to assess the changes in baroreceptor function. We describe the clinical events associated to BRF after surgery, baseline patient's demographics, characteristics, comorbidities. Additionally, clinical and a quantitative evaluation of baroreceptor sensitivity were conducted using the Composite Autonomic Severity Score (CASS).

RESULTS

From 1986 to 2020, a total 146 CBT resections were performed in 132 patients in our institution. Tumors were removed bilaterally in staged procedures in seven patients with a mean age of 61 years (Standard Deviation 11), six (85%) were females, and there was no family history of paragangliomas. The clinical presentation were palpable masses in 5 (71%), and odynophagia in 2 (29%) cases; malignant histopathology following surgery was found in one case. BRF occurred in one patient after unilateral CBT resection, consisting of bradycardia and a 40 s asystole that was not previously associated to BR sensitivity. Three (43%) patients presented BRF in the immediate postoperative period of the contralateral CBT excision, consisting of volatile hypertensive crisis in two cases, and supraventricular tachycardia in one. All the patients developed (100%) chronic baroreceptor sensitivity symptoms consisting in syncope, vertigo and fatigue in 4 (57%), tachycardia in 2 (28%), and orthostatic headache in one (14%). Autonomic testing showed mixed sympathetic and parasympathetic failure in five (71%), severe sympathetic failure in 1 (14%), and parasympathetic dysfunction in one patient (14%).

CONCLUSIONS

Postoperative autonomic assessment confirmed BRF in all studied patients that underwent staged bilateral CBT resection with mixed, sympathetic, and parasympathetic dysfunction. Further studies are necessary to evaluate the incidence and physiological mechanisms of these sequelae to anticipate possible complications and offer the appropriate perioperative management.

Microsurgery in carotid body paraganglioma

Objectives

In carotid paraganglioma surgery, magnification is crucial to properly evaluate the anatomical relationships between mass, carotid wall, cranial nerves, tumour vascular supply and fascial envelope. The aims of this study are to describe the microsurgical technique, along with the underlying microsurgical anatomy, and to assess outcomes in terms of disease control, complications and functional results.

Methods

Twenty-six patients, accounting for 29 carotid paragangliomas, treated with microsurgery by the same senior surgeon over a 35-year period, were included.

Results

No carotid injury requiring repair, nor peri- or post-operative stroke occurred in this series. No surgical injury of the main trunk of VII to XII cranial nerves occurred. Complete excision was obtained in all cases and no recurrence was observed during follow-up.

Conclusions

The small study size and its retrospective nature suggests caution; however, our results show that microsurgery can allow a safe and precise dissection of the carotids and nerves.

Surgical outcomes for carotid body tumour resection without preoperative embolization: a 10-year experience

Background

Carotid body tumours (CBTs) are neoplasms originating from the paraganglionic cells of the carotid body. Excision is the main route of treatment. This study sought to assess the surgical outcomes of post-carotid body tumour resection without preoperative embolization and discern any underlying relationships between modified Shamblin classes (MSC) and related complications.

Methods

A retrospective medical record review of prospectively collected data is performed at Sulaymaniyah Teaching Hospital between 2008 and 2019, for 54 patients. Presurgical and postsurgical variables such as comorbidities and complications were noted, respectively.

Results

Patient ages ranged between 26 and 60 years (x̄=40.06) with a minimal female predominance (57.4%). Complications included one minor stroke. MSC and postoperative complications were significantly related (P≤0.001). Our analyses also suggested a significant relationship between intraoperative blood loss and the incidence of postoperative complications (P=0.001, χ²=25). The MSC III subtype was significantly associated with intraoperative blood loss (P=0.000), length of stay (P=0.000), and operating time (P=0.001).

Conclusions

Our study purports a strong relationship between greater MSC and complications of all types. As such, surgeons may benefit from preoperative strategies to minimize complications.

Our Experience in Subadventitial Dissection vs. Intracapsular Dissection Technique of Carotid Body Tumors Surgery

This study provides a single-center experience involving intracapsular dissection for Shamblin II carotid body tumors (CBTs) and compares the outcomes with the classic technique of subadventitial resection. Based on the preliminary results, it seems that the enucleation technique facilitates the dissection of carotid body tumors, offering protection to cranial nerves and the internal/external/common carotid artery by utilizing the capsule as a barrier. The classic subadventitial resection approach and the enucleation technique have comparable postoperative complications. However, it is crucial to continue following the patients who underwent these resection techniques to determine the long-term outcomes. Moreover, the enucleation technique significantly reduces surgery duration and intraoperative blood loss.

Malignant carotid body tumors: What we know, what we do, and what we need to achieve. A systematic review of the literature

Malignant carotid body tumors (MCBT) are rare and diagnosed after detection of nodal or distant metastases. This systematic review (SR) focuses on MCBT initially approached by surgery. Preferred Reporting Items for SR and Meta-Analysis (MA) guided the articles search from 2000 to 2023 on PubMed, Scopus, and Web of Science. Among 3548 papers, 132 (337 patients) were considered for SR; of these, 20 (158 patients) for MA. Malignancy rate was 7.3%, succinate dehydrogenase (SDH) mutation 17%, age at diagnosis between 4th and 6th decades, with a higher prevalence of females. MCBTs were mostly Shamblin III, with nodal and distant metastasis in 79.7% and 44.7%, respectively. Malignancy should be suspected if CBT >4 cm, Shamblin III, painful or otherwise symptomatic, at the extremes of age, bilateral, with multifocal disease, and SDHx mutations. Levels II-III clearance should be performed to exclude nodal metastases and adjuvant treatments considered on a case-by-case basis.

A Global Bibliometric Analysis of the Top 100 Most Cited Articles on Carotid Body Tumors

The carotid body, situated at the common carotid artery bifurcation, comprises specialized glomus cells responsible for sensing blood oxygen, carbon dioxide, pH, and temperature changes, crucial for regulating breathing and maintaining oxygen homeostasis. Carotid body tumors (CBTs), arising from these cells, are rare, representing only 0.5% of head and neck tumors, often presenting as benign, slow-growing, vascularized masses. In February 2023, this bibliometric analysis was conducted, which involved screening 1733 articles from the Web of Science database. The screening process was based on citation count, and articles were selected for inclusion based on specific criteria that focused on CBTs located within the carotid bifurcation. Rigorous selection involved independent screening and data extraction by four authors. The top 100 articles, published between 1948 and 2019, totaled 6623 citations and were authored by 98 unique first authors from 22 countries and 77 institutions, spanning 42 journals. Treatment articles were the predominant category, comprising 49% of the literature. This analysis offers insights into publication trends, identifies literature gaps, and outlines areas of research focus, providing a valuable resource to guide future studies on CBTs.

High incidence of occult familial SDHD cases amongst Czech patients with head and neck paragangliomas

Introduction

Head and neck paragangliomas (HNPGLs) are rare neuroendocrine tumors, which are mostly benign in nature. Amongst all genes, Succinate Dehydrogenase Subunit D (SDHD) is the most commonly mutated in familial HNPGLs. In about 30% of HNPGLs, germline mutations in SDHD can also occur in the absence of positive family history, thus giving rise to "occult familial" cases. Our aim was to evaluate the pattern of SDHD germline mutations in Czech patients with HNPGLs.

Materials and methods

We analyzed a total of 105 patients with HNPGLs from the Otorhinolaryngology departments of 2 tertiary centers between 2006 - 2021. All underwent complex diagnostic work-up and were also consented for genetic analysis.

Results

Eighty patients aged 13-76 years were included; around 60% with multiple PGLs were males. Carotid body tumor was the most frequently diagnosed tumor. Germline SDHD mutation was found in only 12% of the Czech patients; approximately 78% of those harboring the mutation had negative family history. The mutation traits had higher affiliation for multiple tumors with nearly 70% patients of ≤ 40 years of age.

Conclusion

An SDHD mutation variant was shared amongst unrelated patients but no founder-effect was established. Our findings confirmed that the pattern of SDHD mutation distribution amongst HNPGLs in Czech Republic differs from most studies worldwide.

Predictors for postoperative cranial nerve complications in carotid body tumor resection: a retrospective cohort study

INTRODUCTION

Carotid body tumors (CBTs) are slow-growing benign tumors. Therefore, surgical resection is considered in case of tumor growth. The timing of surgery is of the utmost importance as the risk of iatrogenic surgical complications increases when resecting larger tumors, whereas on the other hand, resections for asymptomatic small CBT should be prevented. The primary aim of this study was to identify which tumor size or dimension is most accurate to predict nerve injury in patients undergoing resection of a CBT.

MATERIAL AND METHODS

This retrospective cohort study included patients who underwent surgical resection of CBT at the university hospital in South-Holland. Baseline patient characteristics and tumor measurements were retrieved from the medical records. The authors assessed how the different methods of measuring the size of the tumor were interrelated using Pearson correlation. Logistic regression was used to assess which variables were independently associated with nerve injury, including age at surgery, Shamblin classification, and those dimensions that captured different aspects of tumor size (rather than measuring the same as shown by high correlations) as possible independent variables.

RESULTS

In 125 patients, 143 CBTs were resected whereof in 35 cases cranial nerve injury occurred, (transient in 16 cases and permanent in 19 cases). The risks for nerve injury increased with larger tumor size and the Shamblin classification. Logistic regression analysis showed that the anterior-posterior (AP) diameter significantly increased the odds of a nerve injury, a doubling for every 1 cm increase in AP diameter [odds ratio (95% CI) 2.12 (1.29-3.48), P =0.003].

CONCLUSION

This study shows that measured tumor size in the AP plane is a strong predictor for postoperative nerve injury of a CBT resection. This predictor can be used in the daily clinic to give insight in operative risks. More research is needed in order to select the most appropriate time window for CBT resection.

Endocrine causes of hypertension: literature review and practical approach

Hypertension (HTN) affects more than 30% of adults worldwide. It is the most frequent modifiable cardiovascular (CV) risk factor, and is responsible for more than 10 million death every year. Among patients with HTN, we usually distinguish secondary HTN, that is HTN due to an identified cause, and primary HTN, in which no underlying cause has been found. It is estimated that secondary hypertension represents between 5 and 15% of hypertensive patients [1]. Therefore, routine screening of patients for secondary HTN would be too costly and is not recommended. In addition to the presence of signs suggesting a specific secondary cause, screening is based on specific criteria. Identifying secondary HTN can be beneficial for patients in certain situations, because it may lead to specific treatments, and allow better control of blood pressure and sometimes even a cure. Besides, it is now known that secondary HTN are more associated with morbidity and mortality than primary HTN. The main causes of secondary HTN are endocrine and renovascular (mainly due to renal arteries abnormalities). The most frequent endocrine cause is primary aldosteronism, which diagnosis can lead to specific therapies. Pheochromocytoma and Cushing syndrome also are important causes, and can have serious complications. Other causes are less frequent and can be suspected on specific situations. In this article, we will describe the endocrine causes of HTN and discuss their treatments.

Carotid Body Tumor in a 26-Year-Old Male Patient Managed With Preoperative Embolization

Carotid body tumors are rare, highly vascularized neuroendocrine tumors that arise near the bifurcation of the common carotid artery (CCA). Controversy exists in the management of those tumors about whether preoperative embolization facilitates surgical excision and decreases perioperative complication risk. We present the case of a 26-year-old patient with a carotid body tumor manifesting as a painless pulsatile mass in the anterior triangle over the left side of the neck and provide details of the preoperative diagnostic steps. Treatment included preoperative embolization of the tumor followed by surgical excision after 48 hours to safely address this rare pathology, resulting in a favorable outcome for the patient.

Preoperative Embolization in Surgical Resection of Cervical Paragangliomas: Usefulness and Current Evidence

BACKGROUND

Cervical paragangliomas (CPG) are slow-growing tumours, most of which are highly vascular, making surgical resection challenging. Preoperative embolisation of afferent arteries has been recommended to facilitate operative dissection, reduce perioperative blood loss, and shorten the duration of the operation. However, there is conflicting evidence on the benefits of preoperative embolisation on surgical outcomes, operative time, and bleeding.

OBJECTIVES

The objective of this study was to compare the perioperative parameters and outcomes like duration of surgery, blood transfusion, duration of stay in the ICU, cranial nerve injuries, and postoperative stroke between patients who underwent excision of CPGs with and without preoperative embolisation.

METHODS

This is a retrospective study conducted at the Division of Vascular Surgery, Sree Chitra Tirunal Institute of Medical Sciences and Technology, Thiruvananthapuram, Kerala, India. The study included a review of the medical records of 32 patients who underwent excision of CPGs. Patients who underwent surgical resection without preoperative embolisation (SR) were compared with those who underwent surgical resection with embolisation (SREMB). Statistical analysis was done in R statistical software (R Foundation for Statistical Computing, Vienna, Austria). Categorical variables were reported in absolute numbers and percentages continuous variables were compared with an unpaired Mann-Whitney U test. The chi-square test was used to compare the categorical data.

RESULTS

Out of 32 patients included in this study, 13 (40.6%) patients were included in the SREMB group. Between the two groups, there were no significant differences in operative time (120 vs. 150 minutes; p = 0.59), blood transfusion requirement (0.69 vs. 0.37 units; p = 0.39) and ICU stays (1 vs. 1; p = 0.56). Postoperative cranial nerve injury was significantly more in the SREMB group (6 vs 1; p = 0.01) but stroke (0 vs 2; p = 0.50) was not statistically significant between the two groups.

CONCLUSION

In this study, we found that there was insufficient evidence to support routine preoperative embolisation in CPG. Hence, preoperative embolisation should only be used in a very select group of patients.

Study on the Influencing Factors of Short-Term Recovery of Neurological Symptoms after Carotid Body Tumor Resection

OBJECTIVE

To compare the differences in the short-term recovery from neurological symptoms (SRN) (≤ 6 months) and clinical characteristics of patients with different Shamblin classifications carotid body tumor (CBT) resection and to analyze the risk factors affecting SRN after surgery.

METHODS

Patients who underwent CBT resection between June 2018 and September 2022 were recruited. Perioperative factors and indicators of the nature of the tumor were recorded. The risk factors affecting SRN after CBT resection were analyzed using logistic regression analysis.

RESULTS

Eighty-five patients (43.86 ± 12.7 years, 46 females) were included, 40 (47.06%) of whom exhibited SRN. Univariate logistic regression showed that preoperative symptoms, surgical side, bilateral posterior communicating artery (PcoA) opening, some indicators of tumor size, operative/anesthesia time, and Shamblin III classification were correlated with postoperative neurological prognosis (all p < 0.05). After adjusting for confounders, preoperative symptoms (OR, 5.072; 95% CI 1.027-25.052; p = 0.046), surgical side (OR, 0.025; 95% CI 0.003-0234; p = 0.001), bilateral PcoA opening (OR, 22.671; 95% CI 2.549-201.666; p = 0.005), distance from the tip of the C2 dens to the superior aspect (dens-CBT) (OR, 0.918; 95% CI 0.858-0.982; p = 0.013) and Shamblin III classification (OR, 28.488; 95% CI 1.986-408.580; p = 0.014) were correlated with postoperative neurological symptom recovery.

CONCLUSION

Preoperative symptoms, surgical side (right), bilateral PcoA opening, a short dens-CBT and Shamblin III classification are risk factors affecting SRN after CBT resection. Early resection is recommended for small-volume CBTs without neurovascular compression or invasion to obtain SRN.

An analysis from the CAPACITY database of outcomes of preoperative embolization before carotid body tumor surgery compared with resection alone

OBJECTIVE

There is no definitive consensus on the impact of preoperative embolization on carotid body tumor (CBT) treatment. The objective of this study was to compare surgical outcomes of patients who underwent preoperative embolization before CBT resection vs patients who underwent resection alone.

METHODS

The CAPACITY registry included 1432 patients with CBT from 11 medical centers in four different countries. The group of patients undergoing CBT resection with preoperative embolization was matched in a 1:6 ratio from a pool of patients from the CAPACITY database, using a generated propensity score with patients who did not underwent preoperative embolization.

RESULTS

A total of 553 patients were included for analysis. Mean patient age was 56.23 ± 12.22 years. Patients were mostly female (n = 469; 84.8%). Bilateral CBT was registered in 60 patients (10.8%). Seventy-nine patients (14.3%) underwent preoperative embolization. Embolized patients had larger CBT sizes than non-embolized patients (33.8 mm vs 18.4 mm; P = .0001). Operative blood loss was lower in the embolized group compared with the non-embolized group (200 mL vs 250 mL; P = .031). Hematomas were more frequent in the non-embolized group (0% vs 2.7%; P = .044). Operative time, rates of stroke, cranial nerve injuries, and death were not statistically significant between groups.

CONCLUSIONS

Embolization before CBT resection was associated with significantly lower blood loss and lower neck hematomas than patients who underwent resection alone. Operative time, stroke, cranial nerve injuries, and death were similar between groups.

Unilateral synchronous masses of the neck revealing a malignant Carotid Body Tumor: A case report and literature review

INTRODUCTION AND IMPORTANCE

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.

CASE PRESENTATION

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.

CLINICAL DISCUSSION

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).

CONCLUSION

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.

Risk Factors for Stroke After Carotid Paraganglioma Surgery

BACKGROUND

The Carotid Paraganglioma Cooperative International Registry (CAPACITY) is an international registry composed of 1,432 patients with carotid body tumors (CBT) from 11 centers from 4 countries. The aim of this study was to identify risk factors for patients who presented stroke after carotid paraganglioma resection.

METHODS

Clinical characteristics and demographics of patients who presented transoperatively and postoperatively stroke from the CAPACITY database were retrospectively gathered. Regression analysis was performed using single logistic regression with Omnibus' test for possible factors that might contribute to present stroke.

RESULTS

Out of 1,432 patients, 8 (0.5%) female patients presented stroke. Median age was 53 years (range: 41-70 years). Six strokes occurred transoperatively, diagnosed clinically in the immediate postoperative period. Of them, none of the patients received any further treatment. Three of them died on postoperative day 2, 3, and 4. Two patients developed stroke during the first 24 postoperative hours, patients showed dysarthria, and aphasia. One of them was reintervened with thrombectomy due to thrombosis of the common carotid artery the other patient was treated conservatively. Median follow-up was 16 months (range: 2-72 months). Single logistic regression analysis revealed a history of diabetes mellitus (odds ratio (OR) 7.62), carotid artery disease (OR 17.51), and vascular lesion (OR 2.37) to have significantly increased odds of stroke during CBT surgery.

CONCLUSIONS

In the present study history of diabetes mellitus, carotid artery disease, and vascular lesion had increased odds of stroke during CBT surgery. Findings are limited by low event rate and even larger cohorts are needed to fully define preventive preoperative strategies for preventing stroke.

Retrospective analysis of carotid body tumor surgical management: roles of preoperative image investigation and preoperative embolization

OBJECTIVE

To analyze the management of carotid body tumors (CBTs), particularly the use of preoperative embolization (EMB) and image features in minimizing surgical complications.

BACKGROUND

CBT surgery is a challenging procedure, and the role of EMB in CBT surgery has remained unclear.

METHODS

A total of 200 CBTs were identified among 184 medical records involving CBT surgery. Regression analysis was used to explore the prognostic predictors of cranial nerve deficit (CND), including image features. In addition, blood loss, operation times, and complication rates were compared between patients who had surgery only versus patients who had surgery along with preoperative EMB.

RESULTS

Overall, 96 males and 88 females were identified for inclusion in the study, with a median age of 37.0 years. Computed tomography angiography (CTA) showed the presence of a tiny gap adjacent to the encasement of carotid vessels, which could help minimize carotid arterial injury. High-lying tumors that encased the cranial nerve were usually managed with synchronous cranial nerve resection. Regression analysis revealed that the incidence of CND was positively associated with Shamblin Ⅲ, high-lying, and a maximal CBT diameter of ≥ 5cm. Among 146 EMB cases, two cases of intracranial arterial embolization occurred. No statistical difference was found between the EBM and Non-EBM groups in terms of bleeding volume, operation time, blood loss, blood transfusion requirement, stroke, and permanent CND. Subgroup analysis revealed that EMB decreased CND in Shamblin III and low-lying tumors.

CONCLUSIONS

CBT surgery should be performed with preoperative CTA to identify favorable factors for minimizing surgical complications. Shamblin Ⅲ or high-lying tumors, as well as CBT diameter, are predictors of permanent CND. EBM does not reduce blood loss or shorten operation time.

Resection of Carotid Body Tumors in Patients of Advanced Age: Experience From a Single Center

INTRODUCTION

Resection of carotid body tumor (CBT) in patients of advanced ages has not been appreciated.

OBJECTIVES

This study aims to assess the clinical characteristics and perioperative comorbidities for CBT resection in patients of advanced age and to validate the application of an "isolated island" technique for extirpation of CBT.

METHODS

Eight patients of advanced age (≥60 years) who underwent CBT resection were enrolled as the study group (SG). Another 29 patients of younger age (<45 years old) underwent CBT extirpation were assigned as the control group (CG). The perioperative issues were compared between these 2 groups.

RESULTS

The "isolated island" technique was successfully applied for resection of CBT in all 37 patients. The prevalence of Shamblin classification I, II, and III tumors in the SG was 12.5%, 62.5%, and 25%; whereas in the CG was 10.3%, 55.2%, and 34.5%, respectively. Bilateral CBT was observed in 7 patients of the CG and none in the SG. Vascular reconstruction was required for 1 (12.5%) patient in the SG, while it was required for 8 (27.6%) patients in the CG. Postoperative vocal cord palsy occurred in 37.5% of patients in SG, whereas the vocal cord palsy (34.5%) and dysphagia (6.9%) were commonly encountered in CG. In addition to postoperative length of stay (P = .004), no significant difference for operative time, intraoperative blood loss, or mortality were observed between these 2 groups (P > .05).

CONCLUSION

Extirpation of CBT in patients of advanced age is rationale in appropriately selected patients. The "isolated island" technique is safe for CBT resection with seemingly low complication rates.

[Surgical treatment of cervical neurovascular bundle tumors]

OBJECTIVE

To determine the main principles of a patient-oriented individual approach to diagnosis and surgical treatment of cervical neurovascular bundle tumors considering the capabilities of neurosurgical hospital.

MATERIAL AND METHODS

There were 92 patients with cervical soft tissue tumors affecting neurovascular bundle. Age of patients ranged from 9 to 81 years (mean 47). There were 65.1% women and 34.9% men. We found chemodectoma (47.4%), neurofibroma (15.8%), neurinoma (13.2%), papillary thyroid cancer (5.3%), salivary gland heterotopia (5.3%), salivary gland adenocarcinoma (5.3%), Hodgkin lymphoma (2.6%), hemangioendothelioma (2.6%) and cavernous lymphangioma (2.6%). Diagnostic algorithm included neurological examinations, Doppler ultrasound of supra-aortic arteries, transcranial ultrasound of cerebral vessels, MRI of cervical soft tissues, CT-AG, MR-AG, CT-perfusion, direct selective angiography.

RESULTS

A total of 94 surgical interventions were performed. All surgeries were performed using surgical optics and neurophysiological monitoring of cranial nerves IX, X, XII. We chose resection technique depending on localization, histological features and blood supply of tumor. En-bloc resection was performed in 46 cases, removal of fragments - in 23 cases, intracapsular resection of tumor followed by resection of the capsule - in 26 cases. Total and subtotal resection was performed in 68 (72%) and 23 (24%) cases, respectively. Three (4%) patients underwent partial resection of infiltrative tumors for carotid artery decompression and histological analysis. In 76% of cases, baseline symptoms of disease regressed after surgery. Persistent moderate bulbar disorders were observed in 16 patients (17%). Ischemic complications with additional surgical interventions were observed in 2 cases.

CONCLUSION

Patients with cervical soft tissue tumors require individual approach regarding choosing the optimal surgical treatment including possible preoperative embolization of tumor, en-bloc or intracapsular resection and carotid artery repair.

Safe management of carotid body tumor resection without preoperative embolization: an Ecuadorian high-altitude cities experience

Carotid body tumors (CBTs) are a neoplasm that affects the carotid glomus. This study aims to improve the management of CBTs in Ecuador. This single-center, retrospective observational study was conducted at the Instituto de la Tiroides y Enfermedades de Cabeza y Cuello (ITECC). We included adults with CBTs, between January 2019 and August 2022. A total of 15 patients with CBTs were included. All patients were females living at high altitudes (>2500 m). In the Shamblin classification, 12 tumors were type II, and 3 were type III. Complete tumor resection was performed in all patients without pre-operative embolization. All patients had benign CBTs with a mean follow-up of 17, 73 months. In a time when the medical cost is high mainly in low-income countries such as Ecuador, further investigation should be undertaken in the form of randomized prospective trials to answer who would benefit from the pre-TAE procedure.

Carotid body tumor encounters over a two-decade period in an academic hospital

Carotid body tumors (CBTs) are rare and mostly benign. Research outcomes usually arise from single-center data. We conducted this study to present the characteristics and outcomes of patients who underwent surgical resection of CBT at our hospital over the past 20 years. In this retrospective review, the records of CBTs in our hospital were reviewed between 1998 and 2021. All patients who underwent CBT resection were included. The follow-up period was 12 months. A total of 44 CBTs were treated in our hospital. The male-to-female ratio was 1:2.4. Only 4.5% of patients had Shamblin I tumors. Patients with Shamblin II and III tumors were 56.8% and 38.6%, respectively. Duplex scan was used to diagnose CBT in all of the patients. The majority of our patients (97.7%) did not receive any preoperative embolization despite an average tumor size of 4.9 cm. Cranial nerve injuries were observed in 29.5% of cases. Meanwhile, stroke was reported in only two cases (4.5%). No deaths were encountered. Surgery is the definitive treatment for CBT. Size and local extension appear to be the main reasons for adverse events rather than surgical techniques. Our results are consistent with those of previously published studies. Good outcomes are expected in high-volume centers with appropriate preoperative imaging.

Carotid paragangliomas. Alternatives for presurgical endovascular management

Carotid paragangliomas (CP) are rare tumors, representing 0.6% of the head and neck tumors. These tumors have their origin in the carotid body located in the adventitia of the vascular wall of the carotid bifurcation. Among their principal characteristics are hypervascularity, primarily dependent on branches of the external carotid artery, the proximity and possible involvement of the cranial nerves IX, X, XI, XII, and extension to the base of the skull. Complete surgical resection is the first line of management; however, this procedure can be a surgical challenge due to the potential risk of bleeding, intraoperative neurovascular injuries, and prolonged surgical time. Tumor embolization, carotid stenting, and tumor embolization with carotid stenting have been developed as alternative presurgical endovascular techniques that decrease tumor vascularity and/or provide structural vascular support, reducing bleeding and facilitating tumor dissection. Two cases of carotid tumors of the same classification, Shamblin II, are presented, one treated by preoperative embolization and the other managed with a carotid stent; the indications, advantages, and possible complications of each one are discussed. Two cases of Shamblin II carotid tumors are presented, one treated preoperatively with a carotid stent and the other with preoperative embolization. A literature review was carried out, with a search in PubMed that includes case reports, case series, review articles, meta-analyses on CP, presurgical tumor embolization, presurgical carotid stent placement, and surgical treatment of carotid body tumor. Hypervascularity and adhesion to the carotid wall are the leading causes of difficulties in surgical resection of CP. Optimal tumor embolization and/or preoperative carotid stent placement reduce intraoperative bleeding and provide vascular structural support, reducing intraoperative and postoperative complications.

Two stage, hybrid endovascular and open surgical approach to treat difficult carotid body tumors

OBJECTIVE

Present the feasibility, applicability, clinical effectiveness, and results of complicated Shamblin II or III carotid body tumors treated with a two-stage hybrid surgical approach.

MATERIALS AND METHODS

Retrospective, observational, cross-sectional, descriptive study of the successful treatment of 16 cases of difficult Shamblin II or III carotid body tumors, consisting of a two-stage surgical approach. We conducted a retrospective, observational, cross-sectional, descriptive study of a series of patients with complicated Shamblin II or III carotid body tumors, which we treated with a two-stage hybrid surgical procedure, in which we first placed a carotid endoprosthesis and 45 days later performed surgical resection of the tumor, following our originally published technique. This study was conducted from February, 2007 to November, 2019, in a third level care centre.

RESULTS

We treated 16 patients with a mean age of 50.5 years. All resided at more than 2000 meters above sea level. In all 16 a complete resection was performed. The average duration of surgery was 103.9 min, the average intraoperative bleeding was 69 ml. There were three cases of neuropraxia. The ansa cervicalis nerve had to be sectioned in three cases and there was permanent upper laryngeal nerve injury in two cases. There were no permanent cerebrovascular injuries from placement of the endoprostheses. One patient developed transient cerebral ischaemia (TIA) with no long-term sequelae. There were two cases of asymptomatic late occlusion of the endoprostheses. The average initial volume of the tumors was 54.4 cc. The average tumor volume 35 days after implant of the endoprosthesis was 30.9 cc.

SYMPTOMS

Presence of tumors in the neck in all cases and two cases of dysphagia.

CONCLUSION

This two-stage hybrid technique allowed for the complete resection of difficult Shamblin II or III carotid body tumors, with one case of TIA and two with permanent upper laryngeal nerve injuries and without mortality.

Non-Functional Carotid Body Tumors in Patients Without Somatic Mutations May Be Considered for Non-Operative Management

BACKGROUND

Carotid Body Tumors (CBT) are rare neuroendocrine paragangliomas which are typically asymptomatic and benign, with a low rate of biochemical functionality. Historically, early surgical excision was recommended to prevent development of CBT-related complications. Yet, CBT resection can result in significant cranial nerve and vascular injuries. Recent work has shown successful primary observation without resection of non-carotid body, cranial paragangliomas with slow growth and low rate of neuropathies. We hypothesize that primary observation of CBT is safe and may be considered for majority of CBT.

METHODS

Retrospective cohort study of patients at a multi-hospital healthcare system with radiologic identification and/or diagnostic or procedural billing codes for CBT (2000-2019). Tumor size (greatest diameter), associated symptoms, and interventions were recorded at the initial evaluation and throughout follow-up. Multivariable logistic regression investigated the risk of initial surgical resection.

RESULTS

A total of 108 patients (mean age, 59 ± 19 years; 67% female), with 123 CBT (mean diameter 23 ± 12 mm; 52% right) were initially evaluated by otolaryngologists (51%), vascular surgeons (25%), neurosurgeons (8%), or other (16%) medical providers. Fity-five CBT were initially resected, 63 observed, and 5 irradiated. Initial resection was associated with younger age (adjusted odd ratios aOR, 0.95 [95% confidence intervals CI, 0.92-0.97]), male sex (aOR, 4.82 [95% CI, 1.47-15.75]), and evaluation by a vascular surgeon (aOR, 6.17 [95% CI, 2.04-18.63]). Overall median follow-up was 4.7 (IQR, 2.6-9.1) years. Initially observed CBT were on an average stable in size (mean 1 ± 5 mm/year), none became biochemically active, and 2 patients became symptomatic. At the final follow-up, 63 (51%) underwent surgical resection, 54 (44%) observation, and 6 (5%) radiation therapy. Of the 63 surgically resected CBT, 5 (8%) patients had malignant CBT of which 3 (60%) had known somatic mutations (polymerase epsilon [n = 1], succinate dehydrogenase-D gene [n = 2]). Thirty percent of CBT resections had in-hospital postoperative complications, notably including 1 stroke which occurred in an initially observed patient and 16 cranial nerve complications which all occurred in immediately resected patients. Three resected CBT locally recurred, only 1 of which had malignant pathology.

CONCLUSIONS

Patients with newly diagnosed CBT require biochemical functionality and somatic mutation testing. In the absence of these findings, initial observation of CBTs with annual imaging and symptom monitoring may be considered an alternative to immediate resection which demonstrates a high risk of clinically meaningful postoperative complications.

Schwannoma of the Hypoglossal Nerve Mimicking Carotid Body Paraganglioma

Carotid body paragangliomas (CBPs) clinically present as highly vascularized cervical masses with a pathognomonic localization at the carotid artery bifurcation. Following ultrasonography and MRI/CT imaging, surgical resection with optional preoperative embolization is considered as the treatment of choice in most cases. We herein present the case of a 60-year-old female with characteristic clinical signs and imaging findings of a right-sided CBP who finally went to surgical treatment. Intraoperatively, the tumor showed an adherent growth to the hypoglossal nerve that had to be partially resected, resulting in a postoperative nerve palsy. Histological examination of the resected tumor revealed the unexpected diagnosis of a hypoglossal nerve schwannoma. To the best of our knowledge, we herein present the third case reported in the literature of a unilateral hypoglossal schwannoma located at the carotid bifurcation mimicking clinical symptoms, imaging and intraoperative findings of a CBP.

Beneficial effects of preoperative superselective embolization on carotid body tumor surgery: A 13-year single-center experience

Purpose

This study presented our 13-year experience managing patients with CBTs (carotid body tumors) and was aimed to investigate the impact of pre-TAE (preoperative transarterial embolization) on CBT surgical resection.

Methods

This retrospective study reviewed 169 surgically excised CBTs between May 2007 and October 2020. According to whether to carry out the pre-TAE, the patients were classified into the embolization (EG) (n = 130) and non-embolization groups (NEG) (n = 39). Tumor classification was based on Shamblin criteria and tumor size. The demographic data, clinical features, and intraoperative and postoperative information about the patients were retrieved and analyzed.

Results

The average tumor size was (43.49 vs. 35.44 mm, p = 0.04) for EG and NEG. The mean surgical time (195.48 vs. 205.64 mins, p = 0.62) and intraoperative BL (blood loss) (215.15 vs. 251.41 cc, p = 0.59) were less, but the incidence of revascularization required (29% vs. 33%, p = 0.62) and total complications (26% vs. 36%, p = 0.32) were lower in EG compared to NEG. Similarly, according to the subgroup analysis, no significant differences were detected in the surgical time, BL, adverse events (AEs), and the revascularization in EG when compared to NEG for type I (n = 5 vs. 7), II (n = 105 vs. 27), and III (n = 20 vs. 5), respectively except for the surgical duration in type III (p &lt; 0.05). However, a significantly lower incidence of AEs (230.25 vs. 350 cc, p = 0.038) and a decline in BL (28.57% vs. 48.15%, p = 0.049) in EG were observed compared to those in NEG patients for large CBTs (≥ 30 mm as the cutoff point). No surgery-related mortality was observed during the follow-up.

Conclusions

CBTs can be surgically resected safely and effectively with a need for pre-TAE, which significantly decreases the overall BL and AEs for large lesions (≥ 30 mm).

Current trends in carotid body tumors: Comprehensive review

BACKGROUND

Carotid body tumor (CBT) is a rare neoplasm that has been increasingly studied during the last decades; nevertheless, it continues to be a topic of controversy. This review aims to provide an update on the general features of CBT and particularly review different treatment strategies and primary outcomes.

METHODS

Data for this literature review were identified by PubMed, Scopus, and Medline. 93 articles from the initial search were included, as well as 28 relevant studies utilizing the snowballing method; totaling 121 articles about CBT.

RESULTS

Main features such as anatomy, embryology, genetics, clinical presentation, and diagnosis of CBT are presented, followed by evidence of different treatment strategies such as radiotherapy, preoperative embolization, vascular resection, and vascular reconstruction. Main complications are also discussed.

CONCLUSION

This review summarizes the most critical aspects regarding CBT. Future studies should compare different treatments to attain the best surgical results with lower morbidity rates.

Epidemiology and survival of patients with malignant carotid body tumors in the SEER database

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.

Efficacy and safety of preoperative embolization in carotid body tumor treatment: A propensity score matching retrospective cohort study

BACKGROUND

To assess the efficacy and safety of preoperative embolization (PE) in patients with carotid body tumor (CBTs).

METHODS

In a single-center retrospective cohort study, 127 patients underwent surgical resection of CBTs from January 2003 to December 2019. One-to-one propensity score matching was conducted between patients with or without PE.

RESULTS

Thirty-two (25.2%) patients received PE. After propensity score matching, no statistically significant differences were found in the baseline characteristics of 28 patients in each group. Compared with NPE group, operative time and estimated blood loss (EBL) were significantly reduced in the PE group. The incidence of stroke, perioperative complications, intraoperative blood transfusion, vascular reconstruction, hospital stay, tumor recurrence, and all-cause mortality were not different between the PE and NPE group.

CONCLUSIONS

Preoperative embolization was efficient and safe with a reduction of intraoperative blood loss and operative time during CBT resection.