The surgical resection of a large unfavourable Shamblin type III carotid body tumour (CBT) can be very challenging technically, with many potential significant complications. Preoperative embolization aids in shrinking the lesion, reducing intraoperative blood loss, and improving visualization of the surgical field. Preoperative internal carotid artery (ICA) stenting aids in reinforcing the arterial wall, thereby providing a better dissection plane. A woman presented to our institution with a large right-sided CBT. Failure of the preoperative temporary balloon occlusion (TBO) test emphasized the importance of intraoperative preservation of the ipsilateral ICA. A combination of both preoperative embolization and carotid stenting allowed a less hazardous radical resection of the CBT. An almost bloodless surgical field permitted meticulous dissection, hence reducing the risk of intraoperative vascular and nerve injury. Embolization and carotid stenting prior to surgical resection should be considered in cases with bilateral CBT or a skull base orientated high CBT, and for those with intracranial extension and patients who have failed the TBO test.
Carotid body tumours (CBT) account for 60–78% of all head and neck paraganglioma tumours. They are usually benign, with only 10% reported as malignant. The CBT is a neural crest-derived remnant located at the carotid bifurcation; it is hypervascularized and intimately associated with the adjacent neurovascular structures. These unfavourable factors make the resection of a CBT very challenging. Historically, it has been difficult to achieve a complete removal without permanent disability.
Radical surgical resection is generally recommended for most CBT. Despite advancements in surgical techniques, carotid artery injury, cranial nerve deficits, and cerebrovascular accidents are reported to occur in 10–49%. Radiotherapy can be used as primary, combined, or salvage treatment in patients who are unable to undergo surgery.
We report the case of a patient with a complex CBT who underwent an uneventful radical resection, showing the advantages of preoperative embolization and carotid stenting.
A 39-year-old woman was referred to our hospital with a right-sided neck swelling. She had been asymptomatic for the past 9 years, but the lesion had recently started to grow rapidly. On examination, there was a non-tender pulsatile mass anterior to the sternocleidomastoid muscle. A duplex ultrasonography scan showed a hypervascular mass intimately related to both the internal carotid artery (ICA) and external carotid artery (ECA). A computed tomography (CT) scan revealed a well-defined 3.6 cm × 3.7 cm × 6.1 cm Shamblin type III tumour fully encasing both the ICA and ECA. It also compressed the internal jugular vein (IJV).
Digital subtraction angiography (DSA) and a temporary balloon occlusion (TBO) test were performed under local anaesthesia. DSA delineated a hypervascularized CBT with tortuous and dilated feeder arteries (ascending pharyngeal artery and its branches) ( Fig. 1 ) and a segment of narrowed ICA after its bifurcation. In addition, the posterior communication artery (PCA) was absent in the Circle of Willis. During the TBO test, she immediately developed transient contralateral weakness. This was possibly related to the CBT with carotid stenosis and absence of the PCA. The failure of the TBO test emphasized the importance of the preservation of the ipsilateral ICA during the radical resection surgery. We arranged for the patient to undergo single-stage preoperative feeder artery embolization and ICA stent insertion.
Embolization coils (Cook) were placed in the ascending pharyngeal artery and the proximal and distal ends of the ECA ( Fig. 1 B and C). The embolization coil in the ECA was placed at a distance from the bifurcation to avoid washout out of the coils into the ICA. A self-expanding carotid stent (PRECISE PRO RX 5F, Cordis; 5 mm × 40 mm) was deployed simultaneously ( Fig. 1 D). The carotid stent went beyond the stenosis part of the ICA and extended cranially. The post-embolization and carotid stenting angiogram demonstrated complete devascularization without migration of the coils and carotid stent. The patient remained neurologically intact throughout these procedures.
Surgical resection of the CBT was performed the day after embolization and carotid stenting. The resection was initiated with the identification of the common carotid artery (CCA), ICA, ECA, and cranial nerve X ( Fig. 2 ). A meticulous dissection was then performed caudocranially. Early ligation of the ECA facilitated bleeding control and improved the visualization of the surgical field and CBT mobilization and manipulation. A complete resection of the CBT along the ICA was performed subadventitially. The tumour was radically resected with successful preservation of the ICA, cranial nerves VII, X, XI, and XII, and sympathetic chain. Intraoperative blood loss was only 200 ml and no blood transfusion was required. An anti-platelet regimen was started the day after surgery (acetylsalicylic acid, 325 mg four times daily orally). The patient’s recovery was uneventful and she was discharged home after a week.