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.

Head and neck sarcomas: treatment outcomes in a tertiary referral center in Argentina.

PURPOSE: To analyze the clinical findings, management, and results of oncological treatments and to identify prognostic factors in patients diagnosed with head and neck sarcoma. METHODS: We performed a retrospective analysis including 48 adult patients with primary head and neck sarcomas, treated between 2006 and 2018 in a referral center of Argentina. RESULTS: The median follow-up time was 44 months (range: 4-146 months). Five-year overall survival was 68%. On univariate analysis, radiation-induced sarcomas (p=0.038) had worse survival. Five-year disease-free survival was 58% and local recurrence at 2 years was 22.7%. On multivariate analysis, positive/close resection margins (p=0.031), radiation-induced sarcomas (p=0.037), and mandibular and oral cavity location (p=0.002) were independent prognostic factors associated to local recurrence and shorter disease-free survival. CONCLUSION: Head and neck sarcomas are a rare entity. Surgery is feasible in more than 80% of patients, with an acceptable overall and disease-free survival. Radiation-induced sarcomas, location in the mandible and oral cavity, and close margins were significant prognostic factors in our population.

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.

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.

Linfoma primario difuso de células B grandes de mucosa gingival, en paciente VIH y EBV negativos / Primary gingival diffuse large b-cell lymphoma in HIV/EBR negative patient abstract

El linfoma difuso de células B grandes (LDCBG) es el linfoma más frecuente. La presentación clínica puede ser nodal o extranodal y sus síntomas dependen de la localización tumoral; en la mayoría de los casos están asociados a algún tipo de inmunodeficiencia. Referiremos un caso de LDCBG de presentación atípica en una localización muy infrecuente. Es importante tener en cuenta estas situaciones, ya que pueden simular otros procesos patológicos, retrasando así su correcto diagnóstico y por lo tanto un adecuado tratamiento. (AU)

Diffuse large cell lymphoma B (LDCBG) is the most common type of lymphoma. It´s clinical presentation can be nodal or extranodal and it's symptoms depend where the tumor is located and whether is associated or not with an immunodeficiency disease. We present an atypical presentation of a LDCBG in a very unusual location. It´s important to consider these kind of appearance, as they can mimic other oral pathological processes, delaying their correct diagnosis and therefore an appropriate treatment. (AU)