Ⅰ. INTRODUCTION
Squamous cell carcinoma (SCC) of the maxillary gingiva, maxillary sinus, and palate is rare, accounting for about 3%-5% of all head and neck cancers, and 66% of all maxillary malignancies. Compared with the SCCs in other oral regions, diagnosis of maxillary SCCs is challenging because of varied clinical presentations that often mimic benign diseases such as sinusitis, periodontal disease, inflammatory/reactive tumor-like lesions, and nonspecific granulation tissue1). Maxillary cancers can be classified according to their primary site. In the literature, maxillary cancers have been categorized into carcinomas of the oral mucosa (gingiva, alveolus, and hard palate), carcinomas of the maxillary sinus, and nasal cavity malig-nancies2-5). Recent studies have shown that the localization of gingival, alveolar, and oral SCCs is similar to that of tongue and mouth SCCs6-8).
All SCCs with mucosal elements have a risk of lymph node metastasis. Radical neck dissection or radiotherapy, or both, are commonly performed when tumors are palpable or visible on radiological imaging at the time of initial diagnosis. Patients without any evidence of metastasis have a risk of developing delayed lymph node metastasis. Therefore, selective treatment of regional lymph nodes is widely accepted 9-11).
Major hemorrhage during maxillectomy is an uncommon but potentially life-threatening complication. Acute bleeding must be stopped promptly, with the eventual aim of achieving bleeding control. Ligation of arteries and veins for hemostasis is a feasible treatment choice; however, it is often difficult or impossible to identify and adequately access the culprit vessels. In such cases, ligation of the external carotid artery (ECA) or selective embolization has been the conventionally used strategy for bleeding control.
ECA ligation is rarely performed, due to the availability of interventional embolization. However, ECA ligation has a significant impact on bleeding control in patients with severe and uncontrolled bleeding. This is especially true in situations where selective embolization is infeasible. ECA ligation is the only procedure that can prevent hemorrhagic shock. However, ECA ligation can lead to complications such as bleeding, aneurysm formation, diplopia, muscles pain and facial paresis. On the contrary, ECA ligation during maxillectomy has several advantages, including controlling surgically inaccessible arterial feeders, reducing the surgical blood loss, shortening the surgical procedure time, and increasing the feasibility of total lesion resection. Hence, we present the case report of a 60-year-old man with SCC of the right maxilla that was treated with subtotal maxillectomy and ECA ligation for bleeding control. ECA ligation during maxillectomy, and at the discretion of the operator, can become a routinely performed method of perioperative bleeding control.
Ⅱ. CASE REPORT
A 60-year-old man visited the Department of Oral and Maxillofacial Surgery at Pusan National University Dental Hospital (Yangsan, South Korea) in November 2018 because of an ulcerative gingival lesion in the right maxillary region. The patient previously underwent examinations in other hospitals for his long-term inflammation and persistent pain. Exclusion of malignancy was difficult; therefore, biopsy was performed. The results showed a well-differentiated SCC. Upon presentation in our department, the patient displayed an ulcerative lesion in the right maxilla with delayed healing (Fig. 1). He only had hypertension in his medical history. Routine laboratory tests, positron emission tomography scan, CT and MRI were performed. Laboratory tests results showed normal values. We received written informed consent from the patient for the publication of this report and the use of his medical data. The institutional review board of Pusan National University Dental Hospital approved the study (approval number: PNUDH-2020-005).
1. Radiographic findings
X-ray orthopantomography images depicted bony destruction with sinusitis in the right maxillary posterior region (Fig. 2); this finding was confirmed from the results of computed tomography (CT) and magnetic resonance imaging (Fig. 3, 4). On radiological imaging, the lesion was approximately 2.3 cm in size, with soft-tissue enhancements in the right buccal space and around the maxillary alveolar process. There was no significant cervical lymphadenopathy. In addition, positron emission tomography-CT showed fluorodeoxyglucose uptake in the right maxilla, with a maximum standardized uptake value of 6.7. Hypermetabolic lesions were not observed in the scanned fields. Therefore, based on these findings, a stage IV maxillary cancer was confirmed (Fig. 5).
2. Intraoperative and postoperative findings
A subtotal maxillectomy and selective neck dissection was planned under general anesthesia. The subtotal maxillectomy was performed using the Weber-Ferguson incision, which is used routinely because of the advantages of excellent exposure and minimal scarring as the incision follows the natural skin crease. With an approximately 3-cm diameter resection margin, the lesion along with the right maxillary incisor was removed safely (Fig. 6A-C). The patient did not experience significant cervical lymphadenopathy, but elective neck dissection is performed when there is a risk of occult metastases. Level I and II cervical lymph nodes were dissected during selective neck dissection.
Usually, massive hemorrhage is the most serious and im-minent complication during maxillectomy. In our case, although no hemorrhage occurred intraoperatively, ECA ligation was performed to avoid delayed bleeding postoperatively (Fig. 7A-C).
The patient experienced convulsions and delirium, one of the complications of general anesthesia, on the evening of surgery. Thereafter, there was a risk of rebleeding due to the continuous increase in blood pressure. Although postoperative bleeding was possible, intraoperative ECA ligation was performed to prevent this complication.
Concomitant chemoradiotherapy is generally recommended for patients with locally advanced maxillary cancer. Our patient also had advanced maxillary cancer and underwent 8 weeks of concomitant chemoradiotherapy treatment postoperatively. The surgical site healed 6 months after the lesion excision without any sequelae such as dehiscence or infection. According to the findings of a cone beam CT performed 6 months postoperatively, there was no sign of tumor recurrence, and no buccal bone regeneration was observed in the posterior right maxillary region. Six months postoperatively, a maxillary obturator prosthesis was fabricated for the preservation, support, and improvement of speech (Fig. 8A,B).
3. Pathologic findings
On gross examination, the mass was 3.0 x 1.9 x 1.3 cm in size. The resection margin was abutting to the inferior sur-face, and a safety margin of more than 0.3 cm was ensured for all other areas. The nuclei of the tumor cells were round or oval shaped, hyperchromatic, and malignant, with multiple atypical cell divisions. A peripheral bony invasion was observed, in addition to the oral mucosa and maxillary sinus invasions observed at low magnification (Figs. 9 and 10). The diagnosis of SCC was confirmed by the Department of Clinical Pathology at the College of Medicine, Pusan National University. The immunohistochemistry test produced negative results for p16 and p53.
Ⅲ. DISCUSSION
The prognosis of maxillary cancer remains poor despite aggressive treatment. For successful treatment results, complete surgical resection should be performed with adequate resection margin. However, maxillary cancer is usually diagnosed in the advanced stage, and therefore, achieving complete surgical resection is difficult because of its proximity to important organs such as the eye or cranial nerves, and owing to the risk of intra- or postoperative major hemorrhage.
Greater palatine and maxillary arteries are often the cul-prit vessels in postoperative hemorrhage after maxillectomy. Strategies for bleeding control include packing and ligation of the ECA or maxillary artery. Control of acute bleeding is difficult. Ligation of the affected vessels is the preferred treatment choice, but limited access to the culprit vessel restricts its feasibility. In such cases, an elective intraoperative ECA ligation or embolization is usually performed. Intra- or postoperative ECA ligation is a safe procedure with comparatively fewer complications and can be done within 30 minutes. Furthermore, this procedure minimizes morbidity. Angiography systems with provisions for arterial embolization have been available for 50 years. Presently, this strategy is widely used in the management of postoperative acute bleeding. Embolization confers a selective advantage for ligation and can be performed in cases where surgery is not possible.
The effect of ECA ligation on maxillary arterial hemorrhage was investigated in baboons. The ligation of proximal ECA reduced blood flow by 73%. Additional ligation of the superior thyroid, ascending pharyngeal, lingual, and facial arteries reduced bleeding by 85%”12-13). Complications associated with the ligation of ECA and its branches include hemiparesis, facial paresthesia, and facial pain14).
Our patient with SCC of the right maxilla was treated with subtotal maxillectomy and intraoperative ECA ligation for bleeding control. There is a possibility of bleeding after maxillectomy, and preemptive prevention of bleeding is possible by ECA ligation. Postoperatively, the patient had a good prognosis and is presently on follow-up.
Although performing the procedure on a patient is a limitation of our study, we plan to further investigate preventive ECA ligation and its complications, through including more patients. We suggest performing ECA ligation during maxillectomy, at the discretion of the operator, as a simple, effective, and safe method of perioperative bleeding control.
Ⅳ. CONCLUSION
The objective of this study was to introduce external carotid artery (ECA) ligation on the ipsilateral side, a perioperative bleeding control method with fewer complications. ECA ligation is a simple, effective, safe, and (at the operator’s discretion) recommended method of perioperative bleeding control during maxillectomy.
