Clinical and MRI risk factors predicting post-irradiation carotid blowout syndrome in patients with nasopharyngeal cancer.

OBJECTIVE: To explore the clinical and imaging features of nasopharyngeal cancer (NPC) complicated by acute carotid blowout syndrome (CBS), analyze the risk factors for CBS, and improve diagnostic vigilance for early intervention. METHODS: This retrospective review was conducted between January 2003 and May 2023. Altogether, 49 patients with post-irradiation NPC with CBS and 49 patients without CBS as control group were enrolled. The condition of the patients when CBS occurred was reviewed. Patient characteristics of the CBS and control groups were compared, and binary logistic regression analysis was performed to identify risk factors for CBS. RESULTS: All patients in the CBS group were conscious, and 41 patients had a Karnofsky performance assessment scale score of ≥ 70. After interventional therapy, 43 patients survived (the mean survival time of patients after CBS was 3.2 ± 2.1 years). Compared with the control group, the CBS group had a higher incidence of sphenoid sinusitis (81% vs. 52.4%), osteonecrosis (82.9% vs. 51.2%), artery exposure (29.3% vs. 4.9%), and internal carotid artery injury (61% vs. 29.3%). Osteonecrosis and artery exposure were selected as important risk factor for CBS, with p-values of 0.016 and 0.031, respectively. CONCLUSION: CBS is an important factor that affects the survival of patients with NPC. If internal carotid artery injury, artery exposure, sphenoid sinusitis, and osteonecrosis are present, especially the latter two signs, the possibility of CBS should be considered.

Incidence of Carotid Blowout Syndrome in Patients with Head and Neck Cancer after Radiation Therapy: A Cohort Study.

Carotid blowout syndrome (CBS) is a rare yet life-threatening complication that occurs after radiation therapy (RT). This study aimed to determine the incidence of CBS in patients with head and neck cancer (HNC) undergoing contemporary RT and to explore potential discrepancies in the risk of CBS between nasopharyngeal cancer (NPC) and non-NPC patients. A total of 1084 patients with HNC who underwent RT between 2013 and 2023 were included in the study. All patients were under regular follow-ups at the radio-oncology department, and underwent annual contrast-enhanced computed tomography and/or magnetic resonance imaging for cancer recurrence surveillance. Experienced neuroradiologists and vascular neurologists reviewed the recruited patients' images. Patients were further referred to the neurology department for radiation vasculopathy evaluation. The primary outcome of this study was CBS. Patients were categorized into NPC and non-NPC groups and survival analysis was employed to compare the CBS risk between the two groups. A review of the literature on CBS incidence was also conducted. Among the enrolled patients, the incidence of CBS in the HNC, NPC, and non-NPC groups was 0.8%, 0.9%, and 0.7%, respectively. Kaplan-Meier analysis revealed no significant difference between the NPC and non-NPC groups (p = 0.34). Combining the findings for our cohort with those of previous studies revealed that the cumulative incidence of CBS in patients with HNC is 5% (95% CI = 3-7%) after both surgery and RT, 4% (95% CI = 2-6%) after surgery alone, and 5% (95% CI = 3-7%) after RT alone. Our findings indicate a low incidence of CBS in patients with HNC undergoing contemporary RT. Patients with NPC may have a CBS risk close to that of non-NPC patients. However, the low incidence of CBS could be a potentially cause of selection bias and underestimation bias.

Endovascular Treatment for Primary Tumor Hemorrhage in Oropharyngeal Carcinoma: A Report of Two Cases.

Acute arterial hemorrhage is a damaging and sometimes lethal complication that occurs in patients with head and neck cancer. However, achieving hemostasis can be challenging because of the difficulty in applying pressure in the throat and oral cavity. In this context, endovascular treatment (ET) has been performed in recent years. This report aims to describe the benefits of ET for acute bleeding. Additionally, our findings emphasize the importance of early diagnosis and treatment of tumor-related bleeding, not only for immediate life-saving benefits but also for the potential resumption of irradiation and chemotherapy, which can lead to favorable long-term prognoses in some instances. We describe two cases of primary tumor bleeding where treatment was successful with ET. Neurosurgeons performed these treatments, and effective hemostasis was achieved in both cases. No complications or rebleeding were observed. ET is a better option for hemorrhage from oropharyngeal tumors than for hemorrhage from the main trunk of the carotid artery. The efficacy of ET is dependent on the vessels involved, and early identification of the culprit artery can predict the prognosis. ET should be considered an option for acute arterial hemorrhage in head and neck cancer.

[Treatment strategy of carotid blowout syndrome after radiotherapy for nasopharyngeal carcinoma].

Objective:To investigate the treatment of internal carotid artery rupture after radiotherapy for nasopharyngeal carcinoma. Methods:The clinical data of 7 patients with internal carotid artery rupture after radiotherapy for nasopharyngeal carcinoma from March 2020 to March 2023 were retrospectively analyzed. Results:Skull base osteonecrosis with infection occurred in 4 cases, and tumor recurrence with infection in 3 cases. DSA showed that internal carotid artery rupture was located in the internal carotid artery petrosal segment in 6 cases, and in the paravicular segment in 1 case. Balloon occlusion test（BOT） was performed in 6 patients, of which 3 passed and 3 failed. Vascular treatment included internal carotid artery embolization（4 cases）, false aneurysm embolization 1 case（rebleeding）, coated stent 1 case（rebleeding）, muscle compression during operation（1 case）. Patients with rebleeding received high-flow bypass. Three cases developed cerebral infarction after embolization without severe sequelae after treatment, and no death occurred within 90 days. After bleeding control, all 3 patients with cranial base necrosis received surgical treatment to remove the necrotic bone and tissue flap repair, and 1 patient with recurrence received gamma knife and targeted therapy, 1 patient received immune and surgical therapy, and 1 patient received immune and targeted therapy. Conclusion:Rupture and hemorrhage of internal carotid artery after radiotherapy is related to tumor invasion, tissue injury and local infection after radiotherapy. For those caused by tumor invasion, it is recommended to sacrifice the responsible vessels. For those caused by infection, emergency surgery is recommended and blood vessels preserved. Emergency vascular occlusion remains a life-saving option.

Exposed Embolic Coils Observed in a 64-Year-Old Male With Head and Neck Cancer Following Transarterial Embolization for Carotid Blowout Syndrome.

Background: Delayed migration and exposure of embolic coils is a rare complication of endovascular therapy for carotid blowout syndrome. Methods: A 64-year-old man with recurrent tongue cancer noticed the presence of foreign body in the malignant wound on the right side of his neck. He had undergone transarterial embolization on his right vertebral artery, right common carotid artery (CCA), and internal carotid artery (ICA) for carotid blowout syndrome 1 month prior. On physical examination, exposed spring-like metallic coils were observed, covered in brownish granulation tissue, at the bottom of the malignant wound. Neck radiograph and computed tomography confirmed the extrusion and migration of the embolic coils. Results: In this case, the patient was managed by transection of the exposed coils at the wound surface with close monitoring. Conclusions: Computed tomography angiography is essential for assessing the condition of the remaining embolic coils. In cases with thrombosed parent arteries, a conservative approach, like the transection of exposed coils, can be employed as part of the management strategy.

The Clinical Outcome of Carotid Blowout Syndrome Showing Non-bleeding Angiography.

OBJECTIVE: Patient with carotid blowout syndrome (CBS) may demonstrated non-bleeding digital subtraction angiography (DSA) without identifying pseudoaneurysm or contrast extravasation. Our objective is to evaluate the clinical outcomes for this specific subset of patients. MATERIALS AND METHODS: A retrospective observational study was conducted on 172 CBS patients who received DSA for evaluation of transarterial embolization (TAE) between 2005 and 2022, of whom 19 patients had non-bleeding DSA and did not undergo TAE. RESULTS: The age (55.2 ± 7.3 vs. 54.8 ± 11.1), male sex (17/19 vs. 135/153), tumor size (5.6 ± 2.4 vs. 5.2 ± 2.2), cancer locations were similar (P > 0.05) between both groups; except for there were more pseudoaneurysm/active bleeding (85.6% vs. 0%) and less vascular irregularity (14.4% vs. 94.7%) in the TAE group (P < 0.001). In the multivariable Cox regression model adjusting for age, sex, and tumor size, non-bleeding DSA group was independently associated with recurrent bleeding compared to TAE group (adjusted hazard ratio = 3.5, 95% confidence interval: 1.9-6.4, P < 0.001). Furthermore, the presence of vascular irregularity was associated with segmental recurrent bleeding (adjusted HR = 8.0, 95% CI 2.7-23.3, P < 0.001). CONCLUSION: Patient showing non-bleeding DSA thus not having TAE had higher risk of recurrent bleeding, compared to patient who received TAE. Level of Evidence Level 4, Case Series.

Safety and efficacy of protective stent insertion to prevent carotid blowout syndrome at the distal internal carotid artery in nasopharyngeal carcinoma patients: a comparison with endovascular occlusion.

Background: Carotid blowout syndrome (CBS) frequently occurs at the distal internal carotid artery (distal-ICA) in patients with nasopharyngeal carcinoma (NPC), and remedial treatments run a high risk for neurologic complications. A case-control study was conducted to evaluate the safety and efficacy of protective stent insertion at the distal-ICA to prevent CBS in NPC patients, with a comparison to endovascular coil occlusion. Methods: A total of 28 consecutive NPC patients at high risk of CBS from June 2019 to December 2021 in Shanghai Sixth People's Hospital (a tertiary institution) were retrospectively included and divided into a stent protection group and occlusion group. Technique feasibility, treatment outcomes and neurological deficiency were compared between the two groups by two-sample test. Kaplan-Meier analysis compared patients' survival rates at mid-term follow-up. Results: Stent insertion was performed in 15 patients and ICA occlusion in 13 patients. The technical success rate was 100% in both groups. Procedure-related ischemic stroke was identified in 2 patients (15.4%) in the occlusion group, compared with none in the stent protection group. Bleeding was encountered in one patient in the stent protection group and one patient in the occlusion group, each. During a median follow-up of 10.5 (range, 2-31) months, 3 patients (20%) showed asymptomatic in-stent occlusion in the stent protection group. Notably, the median survival time was significantly longer in the stent protection group than in the occlusion group (23.3 vs. 15.8 months, P=0.04). Conclusions: Protective stenting the distal-ICA was similarly effective in preventing CBS in NPC patients but was safer than endovascular occlusion of ICA.

Endovascular Management of Post-Irradiated Carotid Blowout Syndrome in Patients with Lower Neck Cancers.

OBJECTIVE: Lower neck cancers (LNCs) include specific tumour types and have some different vascular supply or collaterals from other head and neck cancers. This prospective study evaluated the outcome of endovascular management of post-irradiated carotid blowout syndrome (PCBS) in patients with LNC by comparing reconstructive management (RE) and deconstructive management (DE). METHODS: This was a single centre, prospective cohort study. Patients with LNC complicated by PCBS between 2015 and 2021 were enrolled for RE or DE. RE was performed by stent graft placement covering the pathological lesion and preventive external carotid artery (ECA) embolisation without balloon test occlusion (BTO). DE was performed after successful BTO by permanent coil or adhesive agent embolisation of the internal carotid artery (ICA) and ECA to common carotid artery, or ICA occlusion alone if the pathological lesion was ICA only. Cross occlusion included the proximal and distal ends of the pathological lesion in all patients. Re-bleeding events, haemostatic period, and neurological complications were evaluated. RESULTS: Fifty-nine patients (mean age 58.5 years; 56 male) were enrolled, including 28 patients undergoing RE and 31 patients undergoing DE. Three patients originally grouped to DE were transferred to RE owing to failed BTO. The results of RE vs. DE were as follows: rebleeding events, 13/28 (46%) vs. 10/31 (32%) (p = .27); haemostatic period, 9.4 ± 14.0 months vs. 14.2 ± 27.8 months (p = .59); neurological complication, 4/28 (14%) vs. 5/31 (16%) (p = .84); and survival time, 11.8 ± 14.6 months vs. 15.1 ± 27.5 months (p = .61). CONCLUSION: No difference in rebleeding risk or neurological complications was observed between the DE and RE groups. RE could be used as a potential routine treatment for PCBS in patients with LNC.

Brain abscesses following carotid blowout syndrome: a case report.

We report a case of intracranial abscesses development in a patient with head and neck cancer after emergent treatment of carotid blowout syndrome with coil embolization. Our patient is a 60-year-old male who presented with hemoptysis and hematemesis, which raised concerns for impending carotid blowout syndrome. Endovascular occlusion was successfully achieved, and the patient was discharged in stable condition. Ten days later, the patient reported headaches and right facial pain, and magnetic resonance imaging revealed multiple intracranial abscesses. Broad-spectrum intravenous antibiotics were administered, leading to a variable response with some abscesses decreasing in size and others increasing. Seven weeks from discharge, the patient had no neurological deficits, and all abscesses had decreased in size.

Complication of head and neck cancer: Carotid blowout syndrome.

Carotid blowout syndrome (CBS) is an uncommon but potentially life-threatening condition characterized by the spontaneous or traumatic rupture of the carotid artery in the neck. Oftentimes, CBS is due a loss of structural arterial integrity from local radiotherapy or surgical procedures. A vast majority of patients who develop CBS also have a previous diagnosis of head and neck cancer. Due to the specific patient population who develop CBS and its life-threatening nature, CBS should be a part of emergency physicians differential for those who present with a chronic neck wound or neurological symptoms in those with a previous head and neck cancer diagnosis. In this case report, a patient with a history of squamous cell carcinoma of the oropharynx who was treated with chemoradiation therapy, presented to the emergency department with spontaneous bleeding from an existing chronic wound on the left lateral neck. Conservative measures were taken including wound dressing, and the patient was discharged to see dermatology for biopsy of a suspected cancerous lesion. Once the chronic lesion was biopsied, the patient had to be immediately rushed to the operating room due to a brisk pulsatile bleeding from puncturing the carotid artery. Proper wound packing and an ultrasound of the neck for a proper diagnosis may have prevented the need for surgical intervention in this case. Although CBS is not common, complications can lead to death as seen in this case. Timely recognition and proper interventions are critical for preventing potentially fatal outcomes in those with CBS.

Surgical treatment of carotid blowout syndrome after radiotherapy for head and neck malignant tumors: a single-center experience.

To explore the treatments for and manifestations of carotid blowout syndrome (CBS) and to further explore the critical role of high-flow bypass combined with parent artery isolation. The clinical data of nine patients with radiotherapy-related CBS who were admitted to our hospital from March 2020 to March 2023 were retrospectively analyzed. Relevant literature was reviewed. From March 2020 to March 2023, nine CBS patients were admitted to Tianjin Huanhu Hospital, including eight males and one female. Digital subtraction angiography was performed for all the patients; all the pseudoaneurysms were located at the petrous segment of the internal carotid artery. A balloon occlusion test was performed on four patients, which was tolerated by all patients. CT and MRI scans showed seven cases of osteonecrosis combined with infection and two cases of tumor recurrence. Emergency permanent parent artery occlusion was performed on six patients, aneurysm embolization was completed in one case, covered stent implantation was performed in one patient, and three cases were treated by cerebral bypass surgery (including two patients with failed interventional treatment). Rebleeding was found in two patients, and no rebleeding was found in the bypass group. Paralysis was found in three patients, and asymptomatic cerebral infarction without permanent neurologic impairment was found in three patients. Two patients died due to tumor progression. Emergency occlusion surgery is lifesaving in the acute phase of CBS. Endovascular therapy cannot prevent the progression of pseudoaneurysms or lower the recurrence rate of bleeding events. High-flow bypass combined with parent artery isolation is a safe and effective method that may facilitate further surgical treatment. Further research is warranted.

Survival analysis of a comprehensive treatment strategy for internal carotid artery blowout syndrome by nasopharyngeal carcinoma.

OBJECTIVE: To retrospectively analyze the comprehensive treatment strategy for internal carotid artery blowout syndrome (CBS) by nasopharyngeal carcinoma (NPC). METHODS: Of the 311 patients of NPC with carotid artery blowout syndrome admitted at our center from April 2018 to August 2022, 288 were enrolled. RESULTS: The patients were divided into two groups: treatment group (266 cases) and control group (22 cases). After comprehensive treatment, the survival rate of the treatment group was significantly higher than that of the control group, especially within 6 months to the 1 year. Preventive intervention for CBS I type may have considerable benefits. And in the long run, this treatment strategy did not significantly increase the incidence of stroke in the treatment group. CONCLUSION: The comprehensive treatment strategy for ICA-CBS of patients with NPC significantly reduced the mortality of asphyxia due to epistaxis, reduced the incidence of CBS during nasal endoscopy, and finally improved survival rate.

Carotid Blowout Syndrome in Head and Neck Cancer Patients: Management of Patients At Risk for CBS.

OBJECTIVES: Carotid blowout syndrome (CBS) is an acute, rare life-threatening hemorrhage that occurs in patients with a history of head and neck cancer and radiation therapy. The primary objective of this review was to identify risk factors and assess treatment and survival outcomes following CBS. METHODS: A systematic review of published literature was performed. Information including risk factors, treatment, and outcomes of CBS were collected. RESULTS: A total of 49 articles and 2220 patients were included in the systematic review. Risk factors for developing CBS included a history of radiation therapy, wound complications, and advanced tumor stage. The initial management of CBS included establishing a stable airway, gaining hemostasis, and repletion of blood loss. Endovascular and surgical procedures treat CBS with infrequent rates of rebleeding and periprocedural complications. Short-term survival following treatment of CBS shows high survival rates when considering CBS-related complications and underlying disease, however, long-term survival related to the underlying disease demonstrated high mortality. CONCLUSIONS: Identifying patients at risk for CBS enables practitioners to counsel patients on life-saving interventions and expected outcomes following treatment of CBS. Treatment of CBS is associated with high short-term survival, although long-term survival related to underlying disease is low. LEVEL OF EVIDENCE: N/A Laryngoscope, 133:576-587, 2023.

Idiopathic common carotid artery laceration: A case report.

Carotid artery injury is a rare disease often caused by neck trauma or irradiation of head and neck cancer. It is not easy to diagnose quickly without these backgrounds. Herein, we report a case of a 52-year-old man with no history of trauma or irradiation whose carotid artery was found to be injured. It was suggested that patients without any other disease but hypertension could have carotid artery injury. Additionally, it was challenging to detect extravasation from the carotid artery by computed tomography scan and ultrasonography in the emergency department. We should consider the possibility of carotid artery injury when examining patients with sudden neck swelling, even without any history of trauma or irradiation.

Spontaneous carotid blowout of the common carotid artery in a chronically immunosuppressed transplant patient.

Carotid blowout (CB) is a life-threatening surgical emergency with a mortality rate of up to 60%. CB is commonly seen in head and neck cancer patients after surgical and radiation therapy; other causes include iatrogenic, traumatic, or infectious etiologies. We report an unusual case of spontaneous CB presumed to be caused by cytomegalovirus (CMV) in a chronically immunosuppressed transplant recipient. Given the significant mortality of CB and the prevalence of post-transplant CMV, this case highlights an area of further investigation regarding the association between CMV and carotid pathology, as well as the need to include CB as a potential infectious complication in the immunosuppressed population.

Carotid blowout syndrome caused by chronic infection: A case report.

BACKGROUND: Carotid blowout syndrome (CBS) refers to rupture of the extracranial carotid artery and its branches; as a severe complication, it usually occurs after surgery or radiotherapy for malignant tumours of the head and neck. We present a case of CBS caused by chronic infection of the external carotid artery (ECA). In this case, we did not find any evidence of head and neck tumours. CASE SUMMARY: A 42-year-old man was referred to the Emergency Department with a complaint of a lump found on the left side of his neck with pain and fever for 4 d. We diagnosed the condition as neck infection with abscess formation based on physical examination, routine blood examination, ultrasound examination and plain computed tomography (CT) and decided to perform emergency surgery. During the operation, 30 mL of grey and smelly pus was drained from the deep surface of the sternocleidomastoid muscle. The second day after the operation, the patient suddenly exhibited a large amount of haemoptysis and incision bleeding. The enhanced CT showed distal occlusion of the left ECA and irregular thickening of the broken ends of the artery encased in an uneven enhancement of soft tissue density. Infected ECA occlusion and rupture were considered. The patient was transferred to a vascular unit for transcatheter ECA embolization and recovered well. CONCLUSION: Surgeons need to pay attention to vascular lesions caused by chronic infection that may develop into acute CBS.

Head and neck radiotherapy-induced carotid toxicity: Pathophysiological concepts and clinical syndromes.

This review aims at offering a concise cross-section of head and neck radiotherapy-induced carotid toxicity for pathological concepts to emerge and become part of clinical routine. Radiation-induced carotid toxicities such as atherosclerosis, arterial stiffness and arterioradionecrosis result from radiation dose limitation. Atherosclerosis is related to lesions in the epithelial wall. Such lesions are early radiotherapy-related toxicities and depend on the radiation dose. Atherosclerosis may lead to carotid stenosis and stroke. Arterial stiffness and arterioradionecrosis are late toxicities of the connective tissue that have a low alpha/beta ratio. They are risk factors of pseudoaneurysm and carotid blowout syndrome or stroke in some cases. Because all these pathophysiological mechanisms interfere, post-radiation vascular diseases remain particularly severe and difficult to understand.

Stereotactic body radiotherapy optimization to reduce the risk of carotid blowout syndrome using normal tissue complication probability objectives.

PURPOSE: To determine the possibility of further improving clinical stereotactic body radiotherapy (SBRT) plans using normal tissue complication probability (NTCP) objectives in order to minimize the risk for carotid blowout syndrome (CBOS). METHODS: 10 patients with inoperable locally recurrent head and neck cancer, who underwent SBRT using CyberKnife were analyzed. For each patient, three treatment plans were examined: (1) cone-based without delineation of the ipsilateral internal carotid (clinical plan used to treat the patients); (2) cone-based with the carotid retrospectively delineated and spared; and (3) Iris-based with carotid sparing. The dose-volume histograms of the target and primary organs at risk were calculated. The three sets of plans were compared based on dosimetric and TCP/NTCP (tumor control and normal tissue complication probabilities) metrics. For the NTCP values of carotid, the relative seriality model was used with the following parameters: D50 = 40 Gy, γ = 0.75, and s = 1.0. RESULTS: Across the 10 patient plans, the average TCP did not significantly change when the plans were re-optimized to spare the carotid. The estimated risk of CBOS was significantly decreased in the re-optimized plans, by 14.9% ± 7.4% for the cone-based plans and 17.7% ± 7.1% for the iris-based plans (p = 0.002 for both). The iris-based plans had significant (p = 0.02) reduced CBOS risk and delivery time (20.1% ± 7.4% time reduction, p = 0.002) compared to the cone-based plans. CONCLUSION: A significant improvement in the quality of the clinical plans could be achieved through the delineation of the internal carotids and the use of more modern treatment delivery modalities. In this way, for the same target coverage, a significant reduction in the risk of CBOS could be achieved. The range of risk reduction varied depending on the proximity of carotid artery to the target.

Management of Cutaneously Exposed Carotid Stents in Recurrent and Unresectable Head and Neck Cancer.

Objective Carotid blowout syndrome (CBS) is a rare but potentially life-threatening complication of head and neck cancer (HNC) treatment. Patients with CBS are managed with covered stents, limited published information exists regarding the management of delayed complications, specifically cutaneous exposure of stents. Here, we present our experience managing cutaneously exposed carotid artery stents (CAS) in patients with recurrent and unresectable HNC. Methods A single-institution retrospective analysis was performed to identify recurrent HNC patients who underwent CAS placement for CBS and complicated with cutaneous exposure of the stent between 2014 and 2016. Medical records were reviewed with attention to treatment history, pre-, intra-, and postoperative courses, anticoagulation needs, and durability of the reconstruction. Results We identified three patients who presented with a right CAS fully exposed in a large, ulcerative wound. All patients underwent a right pectoralis major myocutaneous flap (PMMF) to cover the exposed stent within 30 days of presentation to our institution. Two of three patients attained adequate coverage of the stent for more than 30 days, while one experienced partial flap dehiscence within 12 days. Two patients developed postoperative chest hematomas, which were managed conservatively. Two of three patients were able to undergo further palliative adjuvant treatments within 60 days of the initial surgical procedure. Conclusion In this small series, durable coverage of an exposed carotid artery with PMMF was successful in two of three patients with extensive disease burden and complex prior treatment history. No mortalities occurred within 30 days postoperatively.

Predictors of survival following carotid blowout syndrome.

OBJECTIVES: Carotid blowout syndrome (CBS) is a rare, life-threatening complication for patients with head and neck cancer (HNC). The primary objective was to identify factors associated with survival following CBS. MATERIALS AND METHODS: A retrospective analysis of HNC patients treated at a single tertiary care hospital with CBS between 2016 and 2020 was performed. A multivariate Cox proportional-hazards model identified independent predictors of survival. A p value of <0.05 was considered significant. Kaplan-Meier survival analysis was performed. RESULTS: 45 patients were identified. The majority were male (80.0%) with a mean age of 64 years at time of blowout. Oropharynx was the most common primary site (48.9%) and 73.3% of patients had stage IV disease. 35 (77.7%) patients had active tumor at time of CBS. 93.3% of patients previously received RT with a mean total dose of 62.5 ± 14.8 Gy. Threatened/type I, impending/type II, and acute/type III CBS occurred in 6.7%, 62.2%, and 31.1% of cases, respectively. Patients underwent either embolization (80.0%) or endovascular stent placement (20.0%). The 30-day and 1-year OS rates were 70.1% and 32.0%, respectively. Primary oropharyngeal tumors (adjusted hazard ratio [aHR], 4.31 [1.30-15.15 95% confidence interval]), active tumor at time of CBS (aHR 8.21 [2.10-54.95]), ICA or CCA rupture (aHR 5.81 [1.63-21.50]), and acute/type III CBS (aHR 2.98 [1.08-7.98]) were independent predictors of survival. CONCLUSION: Primary oropharyngeal tumors, active tumor at time of CBS, ICA or CCA rupture, and acute/type III hemorrhage were independent predictors of survival. Multidisciplinary management and prompt, protocol-directed intervention may improve outcomes following CBS.