Total Temporomandibular Joint Replacement and Simultaneous Orthognathic Surgery Using Computer-Assisted Surgery.

BACKGROUND: Disorders of the temporomandibular joint (TMJ) are frequent and are usually associated with other disorders of the facial skeleton. Surgery might be needed to correct TMJ anatomy and function and, in cases where pathologies coexist, a two-stage corrective surgery might be needed. However, the current fashion of single-stage procedures is feasible with the aid of new technologies such as computer-assisted surgery (CAS). This is a step forward toward performing complex procedures such as a TMJ replacement with simultaneous orthognathic surgery. CAS allows designing patient-fitted prosthesis and more predictable and accurate surgeries. Moreover, intraoperative development can be controlled in real time with intraoperative navigation, and postoperative results can be measured and compared afterwards. AIMS: The primary purpose of this article is to present the protocol used in our institution for orthognathic surgery associated with unilateral and bilateral TMJ replacement with patient-fitted prostheses guided with CAS. MATERIALS AND METHODS: We present two cases to illustrate our protocol and its results. RESULTS: In the first case, the difference in millimeters between planning and surgical outcomes was 1.72 mm for the glenoid component and 2.16 mm for the condylar prosthesis; for the second case, differences in the right side were 2.59 mm for the glenoid component and 2.06 mm for the ramus, and in the left side, due to the anatomy the difference was a little greater, without clinical significance. CONCLUSION: Combined surgery of the midface and mandible with total TMJ replacement is feasible and beneficial for the patient. CAS facilitates the planning and design of custom-fit prosthesis and execution of these procedures.

Clear cell odontogenic carcinoma: a rare pathology with an innovative resolution.

Clear cell odontogenic carcinoma (CCOC) is an uncommon condition that has been considered malignant since 2005. The clinical presentation usually involves an asymptomatic swelling, which typically affects the anterior mandible in middle-aged women; it has neither clinical nor radiological defining features. Immunohistochemical analysis usually aids diagnosis, as clear cells are also associated with other clear cell carcinomas and benign tumors. Radical surgery is the gold standard of treatment and usually needs microsurgical reconstruction with bone transference for restoration of facial anatomy and adequate function.  We present the case of a young woman with CCOC whose tumor removal and reconstructive surgery were planned virtually and assisted by intraoperative navigation. The novelty of the reconstructive procedure was the replacement of the fibula cutting guides for intraoperative navigation of the osteotomies. We present a brief review of CCOC and the benefits of using computer-assisted surgery (CAS) in high-complexity cases like this one.

Predictors of Survival After Head and Neck Squamous Cell Carcinoma in South America: The InterCHANGE Study.

PURPOSE: Head and neck squamous cell carcinoma (HNSCC) incidence is high in South America, where recent data on survival are sparse. We investigated the main predictors of HNSCC survival in Brazil, Argentina, Uruguay, and Colombia. METHODS: Sociodemographic and lifestyle information was obtained from standardized interviews, and clinicopathologic data were extracted from medical records and pathologic reports. The Kaplan-Meier method and Cox regression were used for statistical analyses. RESULTS: Of 1,463 patients, 378 had a larynx cancer (LC), 78 hypopharynx cancer (HC), 599 oral cavity cancer (OC), and 408 oropharynx cancer (OPC). Most patients (55.5%) were diagnosed with stage IV disease, ranging from 47.6% for LC to 70.8% for OPC. Three-year survival rates were 56.0% for LC, 54.7% for OC, 48.0% for OPC, and 37.8% for HC. In multivariable models, patients with stage IV disease had approximately 7.6 (LC/HC), 11.7 (OC), and 3.5 (OPC) times higher mortality than patients with stage I disease. Current and former drinkers with LC or HC had approximately 2 times higher mortality than never-drinkers. In addition, older age at diagnosis was independently associated with worse survival for all sites. In a subset analysis of 198 patients with OPC with available human papillomavirus (HPV) type 16 data, those with HPV-unrelated OPC had a significantly worse 3-year survival compared with those with HPV-related OPC (44.6% v 75.6%, respectively), corresponding to a 3.4 times higher mortality. CONCLUSION: Late stage at diagnosis was the strongest predictor of lower HNSCC survival. Early cancer detection and reduction of harmful alcohol use are fundamental to decrease the high burden of HNSCC in South America.

Head and Neck Tumors: Management of Primary Undifferentiated Pleomorphic Sarcoma.

INTRODUCTION: Sarcomas account for 1% of all tumors originated in the head and neck regions in adults. They constitute a heterogeneous group of tumors of mesenchymal origin with multiple histological variants. The undifferentiated pleomorphic sarcoma (UPS) subtype is the most frequent variant with an incidence range of 2.7-38%. MATERIALS AND METHODS: This retrospective case series was conducted on 11 patients who were diagnosed with UPS and treated in our institution in the last 11 years. RESULTS: According to the results, 26.8% of the sarcomas corresponded to UPS variant. Out of 11 patients, 5 cases were female. The median age of the participants was 58 years (range: 18-74 years). Seven and four patients were T1b and T2b, respectively. Ten patients had no metastasis at the moment of diagnosis. Six patients were categorized as intermediate-grade, and the remaining (n=5) were classified as high-grade. The most frequent location was the scalp (n=3). In the patients undergoing surgery, the mean follow-up duration was 52 months. Disease-free survival (DFS) rates were obtained at 70%, 50%, and 50% in the 1st, 3rd, and 5th years, respectively, with the mean DFS of 36 months. In addition, the overall survival rates in the 1st, 3rd, and 5th years were 100%, 100%, and 83%, respectively. CONCLUSION: The UPS represented the most common histological subtype in our series. They tend to be intermediate or high-grade tumors. An acceptable global survival rate justifies surgical treatment as the main therapeutic tool.

Usefulness of 18F-Fluorocholine Positron Emission Tomography-Computed Tomography in Locating Lesions in Hyperparathyroidism: A Systematic Review.

IMPORTANCE: Identifying parathyroid glands correctly before a surgical procedure is essential to perform minimally invasive surgery. First-line tests with discordant or negative results underscore the need for more accurate imaging tests, thus decreasing the requirement for bilateral neck exploration or reintervention. OBJECTIVE: To review the available evidence to determine positive predictive value, negative predictive value, sensitivity, and specificity in clinical cases in which 18F-fluorocholine positron emission tomography-computed tomography (PET/CT) could be useful as a method to locate the lesions, and the benefits and controversial aspects of the method. EVIDENCE REVIEW: A search was conducted using the PubMed Central and Cochrane Library databases for studies published in English from July 26, 2014, to November 30, 2018, using the search terms 18 choline, 18F choline, 18F-choline, 18 fluorocholine PET CT, hyperparathyroidism, primary hyperparathyroidism, secondary hyperparathyroidism, tertiary hyperparathyroidism, persistent hyperparathyroidism, recurrent hyperparathyroidism, ectopic hyperparathyroidism, and parathyroid adenoma. Other inclusion criteria were reporting at least 1 of the following measurements: negative or positive predictive value, sensitivity, and specificity of 18F-fluorocholine PET/CT in the diagnosis of hyperparathyroidism (HPT). Exclusion criteria were language other than English, use of a tracer other than 18F-fluorocholine, reports of a single case, and studies not related to HPT. The Oxford Centre classifications for levels of evidence were used. FINDINGS: Sixteen studies fulfilled the inclusion criteria, comprising a total of 619 patients. Selected studies included 10 prospective cohort studies, 5 retrospective cohort studies, and 1 case series. Of the subtypes of HPT diagnosed using 18F-fluorocholine PET/CT, 579 were primary HPT, 22 were secondary HPT, 1 was tertiary HPT, and 7 were associated with multiple endocrine neoplasia type I. Pathologically, the neoplasms comprised 459 adenomas, 59 hyperplasia, and 19 double adenomas. CONCLUSIONS AND RELEVANCE: 18F-fluorcholine PET/CT may be indicated when results of first-line tests are negative or discordant and in challenging clinical situations where locating the source of HPT is difficult.

Management Issues in the Treatment of an Ameloblastoma with an Atypical Presentation.

Benign ameloblastoma (BA) is the most common tumor arising from the odontogenic epithelium. Surgical resection with adequate margins is the mainstay of treatment due to the high index of tumor recurrence when not completely excised. Although locoregional spread has been described in the literature, it is very uncommon. We describe the treatment and follow-up of a 22-year-old woman with multiple recurrences and locoregional spread of a mandibular ameloblastoma who was referred to our center after several tumor resections with subsequent reconstructions. After a complete macroscopical removal of a new recurrence, the mandible was primarily reconstructed. A local homolateral recurrence and a second lesion in the contralateral maxilla were detected after 1-year follow-up and accordingly treated. After 4 years the patient showed a new tumor in the temporal fossa and was reoperated. The histopathology was consistent with a BA in all cases. Even though it is rare, locoregional spread of BA has been reported previously. Recurrences discovered during follow-up may require further resections. A close follow-up is mandatory, and treatment of these cases may result demanding requiring a multiple team approach, including oncologists and radiotherapists.