Proposal for updated reporting standards on carotid body tumors

<h2>Abstract</h2> Carotid body tumor is a paraganglioma originating in chemoreceptor cells at the carotid bifurcation. Surgical resection is the gold standard treatment but is challenging due to its vascularity, relation to the carotid arteries and cranial nerves, with risk of bleeding permanent nerve injury and stroke. Radiotherapy is reserved for unresectable tumors. Shamblin, in 1971, described a classification which has been correlated to operative bleeding, the possibility of vascular injury, and the requirement for arterial reconstruction. Clinical palpation evaluating the texture, size, proximal extension in relation to the mandible, combined with computed tomography angiography or magnetic resonance angiography, provides an important preoperative evaluation of the tumor size, volume, extension, distance to the base of the skull, encasement, and infiltration of the carotid arteries and neck structures. Preoperative embolization is used in decreasing complications such as the risk of blood loss. A balloon occlusion test of the internal carotid artery can evaluate the cerebral ischemic tolerance, in case ligation of the internal carotid artery is required. We report the case of a patient with a submandibular mass, pain, progressive growth, dysphagia, and occasional dyspnea. Diagnosis of a carotid body tumor was made based on history, clinical and radiological examinations, with complete 360-degree rotation around the carotid arteries, demonstrating infiltration of the wall of these vessels, and extension to the base of the skull and parapharyngeal space. The extent of the disease required mandible osteotomy and carotid resection. Surgery has been the gold standard for treatment, but the procedure is challenging when there is tumor encasement of the carotid arteries, involvement of cranial nerves, and the possibility of recurrence and malignancy. The importance of considering not only the Shamblin classification but other relevant variables for preoperative planning is mandatory. We review this rare disease and propose the need for updated Reporting Standards on carotid body tumor.