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.

Outcomes and Predictors of Morbidity after Carotid Body Tumor Resection.

BACKGROUND: Carotid body tumors (CBTs) are uncommon neuroendocrine tumors at the carotid bifurcation treated with resection. The goal of this study was to examine patient outcomes after CBT resection and establish predictors of morbidity. METHODS: Patients undergoing CBT resection were identified from the National Surgical Quality Improvement Program (NSQIP) database over 11 years. Demographics, past medical history, preoperative labs, procedural details, morbidity and mortality were recorded. Multivariable logistic regression (MLR) analysis was performed to determine independent predictors of morbidity. RESULTS: From 2010 to 2020, 668 CBT resections were identified. The majority of patients were female (65%) and White (72%) with a mean age of 56 (standard deviation [SD] ± 16). Average body mass index (BMI) was 29.9 (SD ± 7.1). Arterial resection occurred in 81 patients (12%). 6% of patients experienced morbidity, most commonly re-operation (2.4%). Morbidity was more common in patients with higher BMI (33.1 vs. 29.7, P = 0.005), chronic obstruction pulmonary disease (10% vs. 1.9%, P = 0.012), higher American Society of Anesthesiologists (P = 0.005), and lower albumin (3.7 vs. 4, P = 0.016). Morbidity was not increased with arterial resection (P = 1) or based on length of operation (P = 0.169). Morbidity did not impact mortality (P = 0.06) though led to longer length of stay [LOS] (8 days vs. 2.4, P < 0.001). On MLR, preoperative BMI was the only risk factor for morbidity (odds ratio 1.06, 95% confidence interval 1.02-1.1, P = 0.005). CONCLUSIONS: CBT resection is very well tolerated with low stroke rates, morbidity, and mortality. Arterial resection leads to increased transfusion requirements and LOS but did not increase stroke rates, mortality, or overall morbidity. Within the NSQIP database, preoperative BMI was the only predictor of postoperative morbidity, which leads to significantly longer LOS.

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 Management of Carotid Body Tumors: Experience of Two Centers.

BACKGROUND: Carotid body tumors (CBTs) are rare but require surgical resection given their potential for growth and malignancy. For some surgical teams, tumor hypervascularity justifies preoperative embolization to facilitate resection and limit complications. The objective of our study was to evaluate 2 different practices of surgical resection with or without preoperative embolization in a 2-center cohort. METHODS: A consecutive series of patients who underwent CBT surgery, from January 2011 to June 2019, were divided into 2 groups, as to whether they were (embolized CBT [ECBT]) or not (nonembolized CBT [NECBT]) preoperatively embolized. Both groups were compared specifically according to the duration of operation, postoperative complications, and length of stay. RESULTS: Twenty-two patients with a mean age of 48.5 ± 14.3 years were included. In the series, 23 CBTs were resected: 13 were embolized preoperatively; the mean time between embolization and surgery was 2.62 ± 1.50 days. Both groups were comparable based on characteristics of population and tumor, with a mean size of 33.2 ± 11.9 mm. We noted a significant increase in operation duration in the ECBT group: 151 min (±40.9) vs. 87.0 min (±21); P < 0.01. There was no difference between the 2 groups regarding cranial nerve (50% vs. 46%; P = 1), sympathetic nervous system (20% vs. 23%; P = 1), or vascular nerve (20% vs. 23%; P = 0.18) complications. No cerebrovascular accident was identified. The length of stay was 3.60 days (±1.78) vs. 3.73 days (±1.19; P = 0.44). CONCLUSIONS: This study reflects the experience of 2 centers in the management of CBT which is a rare pathology with no standardized treatment. Our series showed no significant difference between the ECBT and NECBT groups regarding postoperative complications and length of hospital stay. The reduction in operating time in the NECBT group remains to be demonstrated.

The value of color doppler ultrasonography combined with computed tomography angiography and magnetic resonance angiography in the preoperative quantification and classification of carotid body tumors: a retrospective analysis.

BACKGROUND: Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) provide accurate vascular imaging information, but their use may be contraindicated. Color Doppler ultrasonography (CDU) provides simple, safe, noninvasive, and reproducible imaging. We therefore investigated the role of preoperative CDU combined with CTA and MRA in the quantification, typing, and diagnosis of carotid body tumors (CBTs). METHODS: We retrospectively analyzed patients with CBTs categorized into group A (type I [n = 1] and type II [n = 10]) or group B (type III [n = 56]) per the intraoperative Shamblin classification. CDU, CTA, and MRA characteristics of CBTs were observed, surgical results were correlated, and the diagnostic threshold of the CBT classification was calculated. RESULTS: CBTs were usually located at the common carotid artery bifurcation, encircling the carotid artery. An increased angle was found between the internal and external carotid arteries. On CDU, CBTs primarily presented as homogeneous hypoechoic masses with clear boundaries, rich flow signals, and a high-speed, low-resistance artery-like flow spectrum. CTA showed uniform or heterogeneous marked enhancement. MRA showed mixed T1 and slightly longer T2 signals and uniform or uneven obvious enhancement. With increases in the lesion size, amount of blood transfused, and operation time, the intraoperative classification level and possibility of skull-base invasion increased. When the maximum diameter of the lesion, the volume of the tumor, the distance between the upper margin of the tumor to the mastoid and the mandibular angle were 3.10 cm, 10.15 cm3, - 3.26 cm, and 0.57 cm, respectively, the largest Youden index was the best diagnostic boundary value for Shamblin type III tumors. CONCLUSIONS: CDU combined with CTA and MRA can accurately evaluate the size and classification of CBTs.

Novel insights into the classification of Shamblin III carotid body tumors from a neurosurgical perspective.

BACKGROUND AND PURPOSE: The classic Shamblin system fails to provide valuable guidance in many Shamblin's III carotid body tumors (III-CBTs) due to the variable forms of carotid arteries and the complex anatomic relationships in parapharyngeal space. We proposed a modified classification to separately divide III-CBTs into different subgroups on the basis of arterial relevant features and anatomical relevant features. MATERIALS AND METHODS: From 2020 to 2023, a total of 129 III-CBTs at a single institution were retrospectively analyzed. All cases were independently classified as arterial-relevant and anatomical-relevant subgroups. The pre-, peri- and postoperative data were summarized and compared accordingly. RESULTS: Among the 129 cases, 69 cases were identified as "Classical type", 23 cases as "Medial type", 27 cases as "Lateral type" and 10 cases as "Enveloped type" according to arterial morphologies. Besides, 76 cases were identified as "Common type", 15 cases as "Pharynx- invasion type", 18 cases as "Skull base-invasion type" and 20 cases as "Mixed type" according to anatomical relationships. "Enveloped type" of tumors in arterial-relevant classification and "Mixed type" of tumors in anatomical-relevant classification are the most challenging cases for surgeons with the lowest resection rate, highest incidence of carotid arteries injury and postoperative stroke. CONCLUSION: The modified classifications provide comprehensive understanding of different III-CBTs which are applicable for individualized treatment in clinical practice.

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.

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.

Clinical Characteristics and Surgical Outcomes of Carotid Body Tumors: Data from the Carotid Paraganglioma Cooperative International Registry (CAPACITY) Group.

BACKGROUND: This study's objective was to conduct a multinational registry of patients with carotid body tumors (CBTs) and to analyze patients' clinical characteristics, treatments, and outcomes. METHODS: Retrospective study from the Carotid Paraganglioma Cooperative International Registry involving eleven medical centers in Bolivia, Ecuador, Mexico, and Spain, of all patients with a CBT who underwent resection between 2009 and 2019. RESULTS: A total of 1432 patients with a CBT surgically treated were included. Median patient age was 54 years (range: 45-63 years), and 82.9% (1184) of the study cohort were female. While at low altitude, the proportion of female-to-male cases was 2:1, at high altitude, this proportion increased to 8:1, with statistically significant differences (p = .022). Median operative time was 139 min (range: 110-180 min), while median operative blood loss was 250 ml (range: 100-500 ml), with statistically significant difference in increased blood loss (p = .001) and operative time (p = .001) with a higher Shamblin classification. Eight (0.6%) patients suffered stroke. Univariate analysis analyzing for possible factors associated with increased odds of stroke revealed intraoperative vascular lesion to present an OR of 2.37 [CI 95%; 1.19-4.75] (p = 0.001). In 245 (17.1%), a cranial nerve injury was reported. Seven (0.5%) deaths were recorded. CONCLUSION: The most common CBT type on this cohort was hyperplasic, which might be partially explained by the high altitudes where these patients lived. Increased blood loss and operative time were associated with a higher Shamblin classification, and the risk of stroke was associated with patients presenting transoperative vascular lesions.

Necessity of Intraoperative Level IIA Lymph Node Dissection in Patients with Carotid Body Tumors: A Retrospective Study of 126 Cases.

BACKGROUND: Carotid body tumors (CBTs) are relatively uncommon neoplasms that rarely have malignant potential. However, malignant CBTs (MCBTs) are still associated with a poor prognosis and the treatment is still challenging clinically. Therefore, we evaluated the necessity of intraoperative level IIA lymph node dissection in patients with CBT. METHODS: The clinical characteristics, intraoperative details, and pathological diagnosis of 126 CBT patients who had undergone surgery were retrospectively reviewed. The patients were divided into 2 groups according to whether level IIA lymph node dissection was performed. The prognosis was analyzed using Kaplan-Meier curves and Cox model multivariate survival analysis. RESULTS: Among the 126 patients, 7 patients (10.3%) in the selective lymph node dissection (SLND) group (68 patients) were diagnosed with MCBTs with evidence of lymph node metastasis. Two patients (3.4%) in the lymph node nondissection (LNND) group (58 patients) were diagnosed with MCBTs later after the second operation because they could not be diagnosed as malignant initially because of the lack of lymph node pathology results although the pathology of the primary lesion showed features of malignancy. The SLND group had a significantly higher relapse-free survival rate than the LNND group (94.1% vs. 79.3%, p = 0.021). Patients with a confirmed diagnosis had a better prognosis than those with insufficient evidence of a malignancy due to the lack of lymph node information. Twenty-nine patients in the SLND group and 26 patients in the LNND group had postoperative nerve injuries, with no significant difference between the groups (p = 0.879). CONCLUSION: Intraoperative dissection of level IIA lymph nodes around the tumor in CBT patients can help improve the diagnosis and prognosis of MCBTs without causing additional cranial nerve injury.

Multispecialty surgical management of carotid body tumors in the modern era.

OBJECTIVE: The objective of this study was to assess the perioperative and long-term outcomes of carotid body tumor (CBT) resection with a multispecialty (head and neck surgery/vascular surgery) approach. METHODS: Our institutional data registry was queried for Current Procedural Terminology codes (60600, 60605) pertaining to CBT excision. These patient records and operative reports were individually reviewed to determine laterality, preoperative tumor embolization, operative time, estimated blood loss, need for intraoperative transfusion, intraoperative electroencephalogram changes, intraoperative division of the external carotid artery, carotid artery repair, resection of the carotid bifurcation, tumor volume, final pathology, cranial nerve injury, stroke, death, and clinical or radiographic evidence of recurrence. RESULTS: From 1996 to 2018, 74 CBT resections were identified in 68 patients (41 [60%] females; mean age, 50.83 years). The mean tumor volume was 9.92 ± 14.26 cm3 (range, 0.0250-71.0627 cm3). Embolization was performed by a neurointerventional specialist in 27 CBT resections (36%) based on size (embolization 14.27 ± 16.84 cm3 vs 7.17 ± 11.86 cm3; P = .063) and superior extension. This practice resulted in one asymptomatic vertebral dissection, which postponed the surgery. There was a trend toward greater blood loss in the embolization group (embolization 437 ± 545 mL vs 262 ± 222 mL; P = .17); however, no transfusions were required in any patient. The mean operative time was also significantly longer in the embolization group (198.33 ± 61.13 minutes vs 161.5 ± 55.56 minutes; P = .03). Three resections had reversible intraoperative electroencephalogram changes, one of which occurred during carotid clamping. These changes resolved with shunting. Eight external carotid resections (11%) and 6 carotid reconstructions (8.1%; two primary, two patch, and two primary anastomosis) were required. Malignancy was identified in four tumors (5.4%), accounting for four of the six carotid reconstructions. There were no postoperative cranial nerve injuries, no strokes, no reexplorations, and no deaths. One patient developed transient dysphagia from pharyngeal tumor infiltration. Long-term follow-up (mean, 43 ± 54 months), available in 61 of the 68 patients (89.7%), revealed three (4.4%) recurrences. CONCLUSIONS: This large, single-institution series demonstrates that a multispecialty team combining two surgical skill sets for the treatment of this rare, challenging condition yields unparalleled low complication rates with short operative times. This approach, including long-term surveillance for recurrent disease, should be considered to optimize outcomes of CBT resection.

Surgical outcomes and factors associated with malignancy in carotid body tumors.

OBJECTIVE: To compare the surgical outcomes of benign and malignant carotid body tumor (CBT), and to evaluate the associated factors of malignant CBT. METHODS: Patients who underwent surgical resection of CBT from 2005 to 2018 in a tertiary center were reviewed retrospectively. The common study follow-up end date was December 31, 2019. The tumor size was measured as the maximum transverse diameter on computed tomography scan. Surgical outcomes of benign and malignant CBT were compared. Associated factors of malignancy were analyzed by multivariate logistic analysis. RESULTS: There were 229 patients undergoing CBT resection. Sixteen patients were diagnosed with malignant CBT. The median follow-up time was 66 months (range, 6-142 months). Basic information including age, sex, course of disease, family history, lesion side, tumor size, and Shamblin classification showed no significant differences between the benign and malignant CBT groups. Patients with malignant CBTs showed a higher rate of preoperative symptoms (31.3% vs 12.2%; P < .05). The rates of vascular reconstruction or repair (P < .01) and neurologic complications (P < .05) were significantly higher in the malignant CBT group. In addition, a significantly longer average procedural time was required for malignant CBTs (P < .05). However, the estimated blood loss and length of hospital stay showed no significant difference. Multivariate logistic regression analysis revealed that the malignant odds of CBT with bilateral lesions (P = .0042; odds ratio, 8.30; 95% confidence interval, 1.84-35.88) or CBT with preoperative symptoms (P = .0016; odds ratio, 7.59; 95% confidence interval, 2.13-27.89) were high. CONCLUSIONS: Compared with benign CBT, malignant CBT is prone to invasive clinical behaviors, resulting in an increased possibility of vascular reconstruction or repair during the surgery as well as postoperative neurologic complications. In addition, the malignant odds of CBT with bilateral lesions or CBT with preoperative symptoms are high.

Outcome of Surgical Treatment for Carotid Body Tumors in Different Shambling Type Without Preoperative Embolization: A Single-Center Retrospective Study.

BACKGROUND: Carotid body tumor (CBT) is the most common head and neck paragangliomas. Surgical resection is the golden standard management for CBT. While preoperative embolization is still controversial, long-term outcomes and perioperative results are still deficient. We, here, presented the outcomes of surgical treatment for CBT without preoperative embolization at our institution. METHODS: In this retrospective study, we collected data from 101 patients who received surgical treatment for CBTs without preoperative embolization from 2011 to 2016. In addition, we attempted to conduct 2 years of follow-up under the guidance of both neurologist and vascular surgeon. Patients' demographics, clinical characteristics, complications, and follow-up results were all analyzed with descriptive statistics. RESULTS: Complete resection of the CBT was achieved in 101 cases (100%). Postoperative adverse events (AEs) mostly observed during hospitalization were as follows: tongue bias (I: 4, 36.4%; II: 8, 19.5%; III: 13, 26.5%), hoarseness (I: 1, 9.1%; II: 4, 9.8%; III: 7, 14.3%), dysphagia (I: 0; II: 2, 4.9%; III: 7, 14.3%), and hematoma (I: 0; II: 0; III: 1, 2.0%). No other serious AEs were observed. The total incidence of AEs in type I patients was 5 (45.5%), 14 (34.1%) in type II, and 28 (57.1%) in type III, and the type III group has significantly higher than the other two groups. At the end of 2 years of follow-up, there were no AEs in type I patients. The number of patients with AEs in type III was greater than that in type II, although there was no significant difference. Based on our findings, 3 most commonly injured cranial nerves (CNs) after surgical resection of CBT were CN XII (hypoglossal nerve, 21.9%), CN X (vagus nerve, 20.3%), and recurrent laryngeal nerve (18.8%). CONCLUSIONS: Surgical management without preoperative embolization for CBT patients is a safe and effective therapeutic approach.

Identifying Factors Influencing Decision Making in Patients Diagnosed with Carotid Body Tumors: An Exploratory Study.

BACKGROUND: Carotid body tumors (CBTs) are rare highly vascularized and slow enlarging tumors arising from the paraganglionic tissue at the carotid bifurcation. Main treatment options for CBTs are surgical resection or "wait and scan" strategy. The choice for either strategy may be equally good medically in many patients. A structured "shared decision making" (SDM) might be helpful for guiding patients. OBJECTIVES: To develop an SDM strategy for the surgical treatment, we aim to (1) identify considerations and factors involved in the decision making of patients with CBTs and (2) evaluate the current practice in our clinic and explore the opinions of patients on their treatment. METHODS: This exploratory study was conducted in patients of the Leiden University Medical Centre (LUMC), The Netherlands. Patients who met the inclusion criteria were invited for a semi-structured interview. All conversations were fully audiotaped and transcripted. RESULTS: Fifteen patients were included and interviewed. Ten of these patients underwent previously surgical resection of at least one tumor. Five patients underwent the wait and scan policy. The most important factors influencing decision making in CBT treatment are family, fears, co-consultants, and doctor-patient relationship. CONCLUSIONS: This study has identified the factors influencing decision making in CBT and should be considered during consultations. The decision for surgery or not was mainly influenced by physician preferences and family members' prior experiences.

Carotid Body Tumor Resection: Just as Safe without Preoperative Embolization.

BACKGROUND: Carotid body tumors (CBTs) are rare entities for which surgical resection remains the gold standard. Given their hypervascularity, preoperative embolization is often used; however, controversy exists over whether a benefit is associated. Proponents of embolization argue it minimizes blood loss and complications. Critics argue cost and stroke outweigh benefits. This study aimed to investigate the impact of embolization on outcomes after CBT resection. METHODS: Patients undergoing CBT resection were identified using the Healthcare Cost and Utilization Project State Inpatient Database for 5 states during the years 2006-2013. Patients were divided into 2 groups: carotid body tumor resection alone (CBTR) and carotid body embolization prior to tumor resection (CBETR). Descriptive statistics were calculated using arithmetic means with standard deviations for continuous and proportions for categorical variables. Patients were propensity score matched on the basis of sex, age, race, insurance, and comorbidity before analysis. Risk-adjusted odds of mortality, stroke, nerve injury, blood loss, and length of stay (LOS) were calculated using mixed-effects regression models with fixed effects for age, race, sex, and comorbidities. RESULTS: A total of 547 patients were identified. Of these, 472 underwent CBTR and 75 underwent CBETR. Mean age was 54.7 ± 16 years. Mean number of days between embolization and resection was 0.65 ± 0.72, (range 0-3) days. When compared to CBTR, there were no significant differences in mortality for CBETR (1.35 vs. 0% P = 0.316), cranial nerve injury (2.7 vs. 0% P = 0.48), and blood loss (2.7 vs. 6.8% P = 0.245). After risk adjustment, CBETR increased the odds of prolonged LOS (OR: 5.3; CI 2.1-13.3). CONCLUSIONS: CBT resection is a relatively rare procedure. The utility of preoperative tumor embolization has been questioned. This study demonstrates no benefit of preoperative tumor embolization.

Carotid Body Tumor Resection: Long-Term Outcome of 67 Cases without Preoperative Embolization.

BACKGROUND: Carotid body tumors (CBTs) are rare tumors in the neck. Surgical resection is the gold standard of treatment. Surgical resection may be complicated by bleeding. Preoperative embolization has recently been introduced for the treatment to reduce the quantity of blood loss; however, the outcomes of this procedure are still under debate. In this article, we have presented the outcomes of patients who underwent surgical resection for CBT without undergoing preoperative embolization in our institution. METHODS: This retrospective study reviewed 67 tumor resection cases who underwent surgical resection for CBTs without undergoing preoperative embolization. Tumor classification was performed as per the Shamblin classification. The demographic, clinical characteristics, and the operative information about the patients were retrieved from the patient records. The obtained data were analyzed with descriptive statistics. RESULTS: The study included 12 male and 55 female patients. The mean age was 51.95 ± 16.59 years. Of the surgically resected tumors; 11 (16.4%) were Shamblin type I, 30 (44.8%) were Shamblin type II, and 26 (38.8%) were Shamblin type III. The mean duration of operation was 109.10 ± 32.36 min. The volume of intraoperative blood loss in the Shamblin type I, type II, and type III groups were 98.64 ± 23.46 cc, 215.33 ± 75.74 cc, and 351.73 ± 62.51 cc, respectively, and they were significantly different among the groups (P < 0.001). The volume of postoperative blood loss in the Shamblin type I, type II, and type III groups were 34.09 ± 10.44 cc, 53.00 ± 20.02 cc, and 62.50 ± 25.11 cc, respectively, and they were significantly different among the groups (P = 0.003). Cranial nerve injury developed in 10 (15.0%) patients. Postoperative stroke developed in 2 (3%) patients. No mortality or persistent nerve injury was observed in association with the injury in the patients during the 1-year follow-up period. CONCLUSIONS: CBTs can be surgically resected safely and effectively without a need for preoperative embolization.

Sudden Death Due to Neck Paraganglioma: A Pediatric Case Report and Review of the Literature.

Neck paragangliomas are relatively rare neuroendocrine nonsecretory tumors. They are mainly observed among adults and are often asymptomatic, causing a frequent delay in diagnosis. In pediatric cases, neck paragangliomas can be associated with adrenergic symptoms that may lead to complications.A report of a sudden death due to a carotid paraganglioma in a young girl is reported. Autopsy revealed a thoracic arotic dissection and a 4-cm jugulocarotidian mass in the absence of traumatic injuries. Histology showed no evidence of underlying aortic disease, including signs of Marfan syndrome, and a paraganglioma. Postmortem biochemistry analysis showed blood metanephrines levels 100 times higher than normal range. The cause of death was an aortic dissection complicating a neck paraganglioma. The manner of death was concluded as natural.Our case highlighted the importance for forensic pathologist to consider the diagnosis of paraganglioma in case of sudden hypertensive complications, especially among young people.

Immunohistochemistry and Mutation Analysis of SDHx Genes in Carotid Paragangliomas.

Carotid paragangliomas (CPGLs) are rare neuroendocrine tumors often associated with mutations in SDHx genes. The immunohistochemistry of succinate dehydrogenase (SDH) subunits has been considered a useful instrument for the prediction of SDHx mutations in paragangliomas/pheochromocytomas. We compared the mutation status of SDHx genes with the immunohistochemical (IHC) staining of SDH subunits in CPGLs. To identify pathogenic/likely pathogenic variants in SDHx genes, exome sequencing data analysis among 42 CPGL patients was performed. IHC staining of SDH subunits was carried out for all CPGLs studied. We encountered SDHx variants in 38% (16/42) of the cases in SDHx genes. IHC showed negative (5/15) or weak diffuse (10/15) SDHB staining in most tumors with variants in any of SDHx (94%, 15/16). In SDHA-mutated CPGL, SDHA expression was completely absent and weak diffuse SDHB staining was detected. Positive immunoreactivity for all SDH subunits was found in one case with a variant in SDHD. Notably, CPGL samples without variants in SDHx also demonstrated negative (2/11) or weak diffuse (9/11) SDHB staining (42%, 11/26). Obtained results indicate that SDH immunohistochemistry does not fully reflect the presence of mutations in the genes; diagnostic effectiveness of this method was 71%. However, given the high sensitivity of SDHB immunohistochemistry, it could be used for initial identifications of patients potentially carrying SDHx mutations for recommendation of genetic testing.

Descending musculospinal branch of the ascending pharyngeal artery as a feeder of carotid body tumors: Angio-architecture and embryological consideration.

INTRODUCTION: Although the ascending pharyngeal artery (APhA) is known as a main feeder of carotid body tumors (CBTs), its detailed architecture and embryological consideration have not been described. The objective of this study was to describe the architecture of a descending feeder of the APhA and to consider its origin embryologically through a review of our CBT embolizations. METHODS: We retrospectively analyzed data from patients with CBTs who underwent transarterial embolization or angiographic examination-only between July 2010 and February 2017. The arterial supply of the tumors, the number of feeder pedicles, the mean tumor size, embolization materials, complication of embolization, and extent of tumor removal were assessed. The embryological origin of feeding artery was considered based on the literature. RESULTS: Eighteen patients with 20 CBTs underwent preoperative embolization or angiographic examination. The number of feeder pedicles was significantly related to the size of the CBT (P = 0.0002). The main feeding artery was the descending branch of APhA, which was hypertrophied and tortuous (18/20, 90%). Embryologically, this artery originated from the musculospinal branch and is termed the "descending musculospinal branch". CONCLUSION: The main feeder of the CBTs was the "descending musculospinal branch" of the APhA and needs special consideration such as dangerous anastomosis for embolization.

Surgical Management of Bilateral Carotid Body Tumors.

BACKGROUND: Carotid body tumors (CBTs) are rare neoplasms located in the carotid bifurcation. The majority of these tumors are unilateral; bilateral CBTs represent approximately 5% of all affected patients, and the recommended treatment is to surgically remove them in staged-planned surgeries. We describe the experience, outcomes, and the surgical management of bilateral CBTs in our institution. METHODS: A retrospective review of CBTs patients was completed; patient demographics, comorbidities, lesion location, anatomic characteristics, surgical techniques, complications, reinterventions, and other factors that may influence outcomes were evaluated. RESULTS: A total of 109 patients with CBTs were treated surgically; of these, 8 had bilateral CBTs (7%); the mean age was 56 years, and 7 (87%) were females. Thirteen surgical resections were performed, and in 2 of the cases, the pathology report was malignant (15%). Five were classified as Shamblin I (31%), 5 as Shamblin II (31%), and remaining 6 as Shamblin III (38%). The mean time between the first and second procedure was of 10.7 months. Complications included one case of neck hematoma requiring evacuation and postoperative neurologic complications occurred in three patients (one patient with facial and two with vocal cord palsies). None of the studied individuals had a family history of CBT, and all of them lived in altitude areas higher than 2000 meters above mean sea level (mamsl). The mean tumor size was 3.55 cm and 2.75 cm for right and left CBTs, respectively. CONCLUSIONS: A better understanding of the clinical characteristics of patients with bilateral CBTs may lead to a more standardized and optimal management with fewer complications and a better quality of life afterward.