Mandibular Tumor Research Articles

BCOR-ITD Rearranged Sarcoma in the Mandible of a 5-Year-Old Child: A Case Report Highlighting Diagnostic Distinction From Odontogenic Fibromyxoma.

The 5th edition of the World Health Organization (WHO) classification of soft tissue and bone has recognized three distinct groups among Ewing-like sarcomas, namely, CIC-rearranged sarcoma, sarcomas with BCOR genetic alterations, and round cell sarcomas with EWSR1:: non-ETS fusions. Sarcomas with BCOR genetic alterations are a distinct clinicopathological group of high-grade tumors, representing 5% of small round cell tumors. BCOR-ITD rearranged tumors commonly manifest as spindle cell sarcomas and many of them display low cellularity with monomorphous cell morphology and myxoid background resembling benign fibroblastic tumors. We present an intriguing case report of a 5-year-old boy diagnosed with a moderately cellular mandibular spindle cell tumor exhibiting BCOR-ITD rearrangement which was initially misdiagnosed as an odontogenic fibromyxoma. This case report illustrates the histological and immunophenotypic findings of BCOR-ITD rearranged sarcoma, requiring a comprehensive immunohistochemical panel and additional molecular tests for accurate diagnosis.

Management of Anesthesia in Mandibular Tumors with Difficult Airway

A 39-year-old female patient with a diagnosis of mandibular tumor underwent mandibleectomy surgery and Free Fibular Flap reconstruction. Preoperative evaluation is carried out on the patient, namely by conducting an anamnesis, physical examination, and supporting examination to determine the problem and conclusion of the patient's physical status. The physical status of the patient is ASA III. During the surgical durante, a tracheostomy is performed with local anesthesia. Next, the patient is positioned head down to undergo the surgical procedure. The operation lasted for 10 hours with stable hemodynamics. Postoperatively, patients are treated in the ICU treatment room, vital signs observation, and postoperative pain management. A closed study by the American Society of Anesthesiologists (ASA) Professional Committee revealed that the risks and severe complications of anesthesia are most often closely related to airway management problems. Success in overcoming complications depends on early detection of symptoms and corrective actions to prevent the situation from worsening. In this patient, airway management based on the Difficult Airway Algorithm other options, local anesthesia with tracheostomy and watershed algorithm was successful with plan A, namely facemask ventilation and tracheal intubation.

Mandibular Defects and Reconstruction Post Oncological Resection in Paediatric Patients

Introduction: Tumours of the paediatric mandible are rare clinical entities, which require a multidisciplinary team management. Surgery is frequently utilized as a modality for local control in the management of paediatric mandibular neoplasms. However, mandibular reconstruction in such age group is more challenging than in their adult counterparts, owing to the developing nature of the mandible and the craniofacial skeleton. Materials & Methods: The medical records of patients below the age of 18 years of age presented to the Paediatric Oncology and Head and Neck Surgical Oncology Departments at the National Cancer Institute of Cairo University from January 2014 to January 2024 with mandibular tumour were reviewed. The review includes; radiological site of the lesion, histo-pathological diagnosis, multidisciplinary team management. Patients that underwent segmental mandibular resection were evaluated for the type of the resultant mandibular defects according to Brown’s classification of mandibular defects and the subsequent reconstruction procedures. Results: Forty-two patients were reported with mandibular neoplasm. Primary mandibular tumours were found in 35 cases (83.3%), of which non odontogenic tumours were diagnosed in 29 cases (69.0%). The anatomical subunits of the mandible; ramus, angle and body were involved in 14 (33.3%), 13 (31.0%) and 15 (35.7%) cases, respectively. Twenty-nine patients underwent segmental mandibular resection. According to Brown’s classification; Class I, Class Ic, Class II, Class IIc, Class III, Class IV and Class IVc were the resultant defects in 0 (0%), 2 (6.9%), 10 (35.5%), 10 (35.5%), 3 (10.3%), 0 (0%), and 4 (13.8%) cases, respectively. Conclusion: The different pathologies of the mandibular neoplasms affecting the paediatric age group frequently involve the ramus of the mandible. With the surgery being the modality of choice in most of such pathologies, the resultant defects following segmental resection and the reconstruction approach in such age group vary greatly from the adult age group. Hence, the free fibular bone segments used for restoration of the ramus projection would be of a relatively larger length. Condylar resection, unfortunately, would hinder the restoration of occlusion relationship, essential for normal development of the maxillofacial skeleton.

Successful Anesthetic Management for Mandibular Neoplasm Resection in a Patient with Osteogenesis Imperfecta: A Case Report

Background: Osteogenesis imperfecta (OI) is a rare genetic disorder characterized by bone fragility and deformities. Patients with mandibular neoplasms and suspected OI require careful anesthetic management to avoid complications. This case report describes the successful anesthetic management of a patient with a mandibular neoplasm and suspected OI. Case presentation: A 33-year-old man presented with a large mandibular tumor causing airway obstruction and difficulty eating. He had physical features suggestive of OI, including short stature, bone deformities, and abnormal tooth growth. Preoperative evaluation revealed a difficult airway due to the tumor and potential cervical spine instability. Anesthesia was induced with propofol and atracurium after securing the airway via ultrasound-guided tracheostomy under local anesthesia. The tumor was resected successfully, and the patient recovered without complications. Conclusion: Anesthetic management in patients with suspected OI and mandibular neoplasms requires careful planning and execution. A multidisciplinary approach, including preoperative evaluation, airway management strategies, and close postoperative monitoring, is crucial for successful outcomes.

Custom Endoprosthesis-Assisted Pediatric Microsurgical Jaw Reconstruction.

Surgical treatment of pediatric maxillary and mandibular tumors can cause significant postresection disfigurement, mastication, and speech dysfunction. The need to restore form and function without compromising growth at the recipient and donor sites poses a particular reconstructive dilemma. This study evaluates outcomes of the custom endoprosthesis (CE) compared with noncustom reconstruction (NCR) and introduces an algorithm using CE to optimize available soft tissue reconstructive options. An Institutional Review Board-approved retrospective review of all patients undergoing maxillary or mandibular reconstruction between 2016 and 2022 was completed. The independent variable of interest was CE utilization. Primary outcomes of interest included hardware failure/removal or exposure, major complications, and revision surgeries. Covariates of interest included patient demographics, medical comorbidities, tumor size, and pathologic diagnosis. Statistical analyses including independent t test, χ2 analyses, and univariate/multivariate logistic regression were performed using RStudio version 4.2.1. Fifty-one patients (37 mandible and 14 maxilla) underwent CE or NCR. Of patients, 37% (n = 19) received CE. Of patients who underwent mandibular reconstruction, there were significantly lower rates of hardware exposure (14.3% versus 47.8%, P = 0.018), failure (7.1% versus 43.5%, P = 0.048), major complications (28.6% versus 78.2%, P = 0.008), and revisions (11.1% versus 50.0%, P = 0.002) in the CE cohort compared with the NCR cohort. The rates of hardware failure, exposure, major complications, and revisions did not significantly differ in maxillary reconstructions, however, CE successfully reconstructed significantly larger defects (179.5 versus 74.6cm3, P = 0.020) than NCRs. Deviating from NCR, the authors propose an algorithm considering anatomical location, extent of resection, and patient age for soft tissue selection. This algorithm yielded improved mandibular reconstructive outcomes and no increase in complications rate in maxillary reconstruction despite larger resection defects. Furthermore, the authors' initial findings demonstrate that CE is a safe option for pediatric maxillary and mandibular reconstruction that may, in addition, facilitate improved form and function.

Solitary ameloblastic fibroma with impacted teeth: A case report

This case report aimed to describe a rare benign mandibular tumour and assess the outcomes of the most recent reviews, between January 2017 and August 2023. Presenting a detailed clinical case, this study advances our understanding of the diagnostic and therapeutic aspects, ultimately improving the management of similar cases in clinical practice.Orthopantomogram (OPG) revealed a well-defined unilocular radiolucency extending from the midline of the ramus and teeth 47 and 48 were submerged at the base of the mandible. In the presented case, a PLANMECA ROMEXIS PROMAX® three-dimensional (3D) maximum (MAX) cone-beam computed tomography (CBCT) device was used for the 3D examination. An intraoral approach was preferred and the tumour was removed in toto by creating a bone window using a W&H® Dentalwerk Bürmoos GmbH Piezomed piezoelectric device, and the bone plates were fixed with 4 MEDARTIS® microplates, with a primary flap closure. A PANORAMIC 1000, 3DHISTECH Ltd® device was employed for the histological investigation.Odontogenic tumours are rare and typically asymptomatic, often discovered incidentally during routine radiographic examinations. Most of these benign lesions heal well after complete excision and require long-term follow-up. Once diagnosed, ameloblastic fibroma (AF) should be treated immediately to avoid malignant transformation.

‘MANDIBULAR DEFECTS’- A NARRATIVE REVIEW

Mandibular defects can result from an assortment of causes, counting injury, tumors, disease, innate irregularities, and surgical resection. Understanding the classifications of these abandons is vital for treatment arranging and remaking. These classifications give an organized approach to diagnosing and arranging the treatment for mandibular absconds. Each framework has its applications and can be chosen based on the clinical situation and the needs of the patient. Mandibular defects taking after ablative surgery for dangerous tumors of the head and neck locale affect both shape and work. Procured segmental defects of the mandible are most commonly auxiliary to extirpation tumor treatment or avulsive traumatic harm. [1] Presently there is no all-around acknowledged classification framework of graphic surgical significance that exists for mandibular absconds taking after mandibular resection or planed mandibulectomy. Most of the accessible classifications are coordinated to mandibular surrenders counting hard surrenders of the mandible after surgical extraction of mandibular tumors or composite surrenders due to different etiologies. [2]

Tumor marrón en la mandíbula como forma de presentación inicial de hiperparatiroidismo primario

Brown tumor (TP) is a benign bone lesion caused by excess osteoclastic activity and hemosiderin deposition as a result of primary or secondary hyperparathyroidism. We present the case of a 71-year-old male patient with a mandibular tumor and bone pain in the lower limbs. He was initially evaluated by the head and neck department who performed excision of mandibular lesion with histological result of giant cells with necrotic and hemorrhagic areas. 3 months later, hypercalcemia was evident, and he was referred to the endocrinology department. The diagnosis of primary hyperparathyroidism associated with skeletal complications was confirmed and parathyroidectomy was scheduled with histological confirmation of parathyroid adenoma. The present case is of interest because of the initial presentation of primary hyperparathyroidism associated with the presence of a brown tumor as a differential diagnosis when evaluating a patient with mandibular bone tumor.

A Mandibular Brown Tumor: A Pediatric Case Report and Summary of Adolescence Cases

Mandibular brown tumors are often radiographically and histologically indistinguishable from cherubism, aneurysmal bone cyst, giant cell granuloma, and odontogenic fibroma. Laboratory findings of hyperparathyroidism (HPT) aid in directing therapy. We present a case of a 14-year-old male with a brown tumor of the mandible associated with secondary HPT due to vitamin D deficiency. Core biopsy exhibited a proliferation of plump spindle cells and osteoclast-like giant cells within variably fibrous stroma. Parathyroid hormone (PTH) levels were elevated to 288 pg/mL (normal 8.5-77.1 pg/mL) and vitamin D was low at a level of 6.9 ng/mL (normal > 20.0 ng/mL). Six months after the introduction of weekly vitamin D supplementation, PTH and vitamin D levels improved but remained abnormal with PTH of 86.8 pg/mL and vitamin D of 9.3 ng/mL. Alongside an improvement in laboratory indices, the tumor character stabilized and became less clinically friable; however, the burden remained unchanged. At 9 months, the patient underwent surgical debulking of the tumor with local soft tissue coverage. A review of pediatric literature was performed, among which 16 patients were identified. Most children who developed brown tumors were found to have secondary HPT and ultimately 44% underwent some degree of surgical debridement of the mass.

Prognostic value of a mandibular canal staging system for primary lesions in patients with lower gingival squamous cell carcinoma: a multicenter, retrospective study.

The Union for International Cancer Control and American Joint Committee on Cancer tumor staging system is used globally for treatment planning. As it may be insufficient for tumor staging of lower gingival carcinomas, we proposed the mandibular canal tumor staging system. In this study, we aimed to compare the two systems for such tumor staging and to identify prognostic markers. This multicenter, retrospective study included patients with lower gingival squamous cell carcinoma who underwent radical surgery during 2001-2018. We compared survival rates (Kaplan-Meier estimator) and patient stratification according to the two systems. The proposed system yielded more balanced patient stratification than the existing system. Progression in the tumor grade according to the proposed system was associated with a poorer prognosis. The 5-year overall and disease-specific survival rates for the entire cohort were 74.9% and 81.8%, respectively. Independent factors affecting overall survival were tumor stage according to the proposed system, excision margins, and number of positive nodes, whereas those affecting disease-specific survival were excision margins and number of positive nodes. Subsite-specific tumor classification should be used for patients with oral cancer, and our results suggest that mandibular canal tumor classification may be effective for patients with lower gingival carcinoma.

A clinicopathological analysis of 151 odontogenic tumors based on new WHO classification 2022: A retrospective cross-sectional study

Background: Odontogenic tumors are a diverse group of lesions with a variety of clinical behavior and histopathologic subtypes, from hamartomatous and benign to malignant. The study aimed to examine the clinical and pathological features of odontogenic tumors in Baghdad over the last 11 years (2011–2021). Materials and Methods: The present retrospective study analyzed all formalin-fixed, paraffin-embedded tissue blocks of patients diagnosed with an odontogenic tumor that were retrieved from archives at a teaching hospital/College of Dentistry in Baghdad University, Iraq, between 2011 and 2021. The diagnosis of each case was confirmed by examining the hematoxylin and eosin stained sections by two expert pathologists. Data from patients' case sheets were collected, including age, gender, location, and histopathological information. The type of lesions was evaluated based on the World Health Organization's most recent classification (March 2022). Results: There were 151 odontogenic tumor during this period. The most common type (39.1%) was Solid ameloblastoma. The mandibular tumors (76.8%) were more than the maxillary tumors (23.2%). The female to male ratio was 1.1:1. The most cases are found between the 2nd and 5th decades of life. Conclusions: Solid ameloblastoma was the most common odontogenic tumor, while primordial odontogenic tumor was the rarest, Odontogenic tumors were slightly more common in females than in males, the most common cases occur in the mandible., the outcome of the study gives valuable information regarding the patients' profile and type of odontogenic tumors over 11 years, which could aid in the early diagnosis and enhance the intervention.

Combined Use of Endoscopic Techniques and Virtual Surgical Planning for Intraoral Approach for Hemi-mandibular Resection and Reconstruction.

The study aimed to describe our experience in using endoscopic procedures to aid hemi-mandibular reconstruction with bone flaps through transoral approach. Five patients with huge benign mandibular tumors underwent transoral mandibulectomy and hemi-mandibular reconstruction, using endoscopy. Facial symmetry, occlusion, bone healing, and mandibular similarity were all evaluated postoperatively. The paired-samples t test was used to compare quantitative data, and a P value less than 0.05 was considered a significant difference. All five patients who received transoral mandibular surgery recovered in terms of TMJ functionality, facial symmetry, and aesthetic results. Endoscopy monitored and ensured that bone flaps were correctly connected and fixed. The accuracy of endoscopy-guided mandibular reconstruction was confirmed by quantitative examination for four cases, which revealed no statistically significant variations between postoperative CT analysis and preoperative virtual surgical planning data. Endoscopy-assisted virtual surgery may resolve concerns with transoral hemi-mandibular reconstruction and broaden indications for mini-invasive mandibular reconstruction. However, only patients with benign mandibular tumors were included in our study, so surgeons should be very cautious if applying this technique to malignant lesions or bony tumors invading soft tissues.

Intelligent electromagnetic navigation system for robot-assisted intraoral osteotomy in mandibular tumor resection: a model experiment.

Mandibular tumor surgery necessitates precise osteotomies based on tumor boundaries; however, conventional osteotomies often lack accuracy in predicting osteotomy positions and planes, potentially leading to excessive resection of normal bone tissues or residual tumors, thus compromising postoperative quality of life and clinical outcomes. Robotic-assisted surgery (RAS) augmented with artificial intelligence (AI) offers precise localization capabilities, aiding surgeons in achieving accurate osteotomy positioning. This study aimed to evaluate the feasibility and accuracy of a robotic magnetic navigation system for positioning and osteotomy in an intraoral surgical trial of a mandibular tumor model. Patient computed tomography (CT) imaging data of mandibular chin and body tumors were utilized to create 3D printed models, serving as study subjects for mandibular tumor resection. Ten pairs of models were printed for the experimental and control groups. The experimental group (EG) underwent osteotomy using a robot-assisted surgical navigation system, performing osteotomy under robotic navigation following alignment based on preoperative design. The control group (CG) underwent traditional surgery, estimating osteotomy position empirically according to preoperative design. Postoperative CT scans were conducted on both models, and actual postoperative results were compared to preoperative design. Osteotomy accuracy was evaluated by positional and angular errors between preoperatively designed and actual osteotomy planes. For ten randomly selected spots on the left and right sides, respectively, the EG group had mean distance errors of 0.338mm and 0.941mm. These values were obtained from the EG group. In the EG group, on the left side, the mean angular errors were 14.741 degrees, while on the right side, they were 13.021 degrees. For the 10 randomly selected spots on the left and right sides, respectively, the CG had mean distance errors of 1.776mm and 2.320mm. This is in contrast to the results obtained by the EG. It was determined that the left side had a mean angle error of 16.841 degrees, while the right side had an error of 18.416 degrees in the CG group. The above results indicated significantly lower point errors of bilateral osteotomy planes in the experimental group compared to the control group. This study demonstrates the feasibility of electromagnetic navigation robot-assisted intraoral osteotomy for mandibular tumors and suggests that this approach can enhance the precision of clinical surgery.

Effect of Perioperative Blood Transfusion on Postoperative Complications of Free-Flap Reconstruction for Oral Cancer: Analysis of Propensity Score-Matched Cohorts

Abstract Background It has been confirmed in other fields that perioperative blood transfusion (PBT) will increase the incidence of complications after free-flap reconstruction and increase the risk of patients returning to the operating room within 48 hours after the initial operation. However, for head and neck tumors, whether PBT is related to postoperative complications is debatable. The aim of this study was to control the demographic and comorbidity characteristics of patients by propensity score matching (PSM) as well as to investigate the relationship between PBT and postoperative complications after oral cancer free-flap reconstruction. Methods A total of 597 patients who underwent microvascular free tissue transfer in two top three hospitals in Southwest China from January 2015 to July 2023 were retrospectively reviewed. The study population was divided based on PBT within 24 hours of the start of the operation and to ensure homogeneity between groups by using the PSM. The primary outcomes were postoperative complications; secondary outcomes were to explore the intraoperative risk factors of PBT. Results A total of 597 patients were included. Among them, 90 patients received a PBT. Those patients were successfully matched with 86 similar patients who did not receive a transfusion on a ratio of 1:1. This study did not find that patients receive a transfusion had a significantly higher risk of vascular pedicle thrombosis (p = 1.000), hematoma (p = 1.000), flap failure (p = 0.398), flap-related complications (p = 0.470), and other medical complications (p = 1.000). After controlling the preoperative confounding factors and adjusting the logistic regression model, it was concluded that the tumor location-mandible (odds ratio [OR] = 19.923, 95% confidence interval [CI]: 1.213–327.302, p = 0.036) and operation time (OR = 1.011, 95% CI: 1.008–1.014, p < 0.001) were the intraoperative risk factors for PBT. Conclusion PBT is not associated with an increased probability of postoperative complications. Mandibular tumor may have a higher risk of PBT.

Cutting guides in mandibular tumor ablation: Are we as accurate as we think?

PurposeTumor margin status is critical in local tumor recurrence and is a significant prognostic factor in head and neck cancer survival. With the introduction of computer-assisted surgical planning, one of the main challenges is the accurate positioning of the surgical cutting guide but there is limited evidence of the accuracy of the 3D cutting guides in mimicking virtually planned osteotomy. This study evaluates the accuracy of osteotomy lines produced by 3D-printed cutting guides and assesses the overall accuracy of mandibular reconstruction. Material and MethodsThe pre and postoperative 3D models were aligned using an automated surface registration feature based on the iterative closest point algorithm. The differences in osteotomy line deviation, linear and angle measurements, and 3D volume quantification of the pre and post models were measured. ResultsWe included 14 patients (8 men and 6 women with ages ranging from 13 to 75 years) with a segmental mandibular resection who met all of the inclusion criteria. The smallest defect size was 4.4 cm, the largest defect was 12.2 cm, and the average was 7.30 cm +/- 2.80 cm. The average deviation between virtually planned osteotomy and actual surgical osteotomy was 1.52 +/-1.02 mm. No covariates were associated with increased inaccuracy of the 3D-printed cutting guides. ConclusionThe finding of this study suggests that virtual surgical planning is an unambiguous paradigm shift in the predictability of the surgical plan and achievement of the reconstruction goals. The 3D-printed cutting guides are a very accurate and reliable tool in translating virtual ablation plans to an actual surgical resection margin.

The Role of BRAF Inhibitors in the Management of Ameloblastoma: A Literature Review.

Ameloblastoma is one of the most prevalent but enigmatic benign odontogenic tumors of the jaw, accounting for approximately 10% of all maxillary and mandibular tumors. This neoplasia is distinguished by exhibiting several clinical and histological variants along with several mutations that affect its behavior. The ameloblastoma treatment plan is determined by the tumor's size, anatomical location, histologic variant, and anatomical involvement. On chromosome 7, there is a proto-oncogene called BRAF. When BRAF is mutated, it becomes an oncogene and continuously produces proteins like MEK and ERK, members of mitogen-activated protein kinase (MAPK). In the signaling pathway, these proteins activate transcription factor inside the nucleus that helps in cell division and growth. Numerous neoplasms have been linked to more than 40 BRAF mutations. The most common one is BRAF proto-oncogene serine/threonine kinase (BRAF) V600E, whose treatment has been linked to a positive outcome. BRAF inhibitors like vemurafenib, dabrafenib, and sorafenib have shown excellent results, especially in metastatic ameloblastoma. BRAF, particularly in the case of metastatic ameloblastoma, inhibitors such as vemurafenib, dabrafenib, and sorafenib, has demonstrated outstanding results. Targeted therapies have been employed as adjuvant therapies to enhance cosmetic outcomes, even though no reports of serial cases demonstrate their effectiveness in ameloblastomas. In the treatment of ameloblastomas, the identification of BRAF V600E and additional mutations as the prime targeted therapies has proven to be a significant breakthrough where surgical treatment was contraindicated. In this article, we review the presence of BRAF V600E mutations, their inhibitors, and targeted therapies in ameloblastoma.

Changes of the facial soft tissue after mandibular reconstruction using vascularized iliac flap.

To reveal the change patterns of the facial soft tissue after applying mandibular reconstruction. 16 Patients with mandibular benign tumor were recruited in this retrospective study. For all patients, segmental mandibular osteotomy and concurrent reconstruction using vascularized iliac flap were conducted. The soft tissue thickness of patients' lower face was measured with CT scans before surgery, 1week, 6months and 1year after surgery. The time-dependent changes of tissue thickness were analyzed. The most significant tissue swelling was 28.86%, at 1week after the surgery. The average increase of tissue thickness was 4.78 ± 5.30mm across patient. After 1year of the surgery, tissue thickness decreased to the level before operation or the level of the healthy side. The thickness of the low-density tissue fluctuated mildly, while the thickness of the high-density tissue fluctuated significantly. The disuse atrophy of the masseter occurred 1week after the surgery, and was reversed after 1year. The removal of the submandibular gland caused depression in submandibular area, which intensified over time. Across patients, soft tissue thickness in the lower face after mandibular osteotomy and reconstruction increased significantly 1week after the surgery, and decreased over time. After 1year, tissue thickness went back to the pre-surgery level, where matched up with the healthy side. We documented the change patterns of the facial soft tissue after mandibular reconstruction. These results can help improve the planning of virtual surgeries and the timing for aesthetic assessment. ClinicalTrials.gov Identifier: ChiCTR2100054103.

MC TRIM Algorithm in Mandibula Phantom in Helium Therapy.

Helium ion beam therapy, one of the particle therapies developed and studied in the 1950s for cancer treatment, resulted in clinical trials starting at Lawrence Berkeley National Laboratory in 1975. While proton and carbon ion therapies have been implemented in research institutions and hospitals globally after the end of the trials, progress in comprehending the physical, biological, and clinical findings of helium ion beam therapy has been limited, particularly due to its limited accessibility. Ongoing efforts aim to establish programs that evaluate the use of helium ion beams for clinical and research purposes, especially in the treatment of sensitive clinical cases. Additionally, helium ions have superior physical properties to proton beams, such as lower lateral scattering and larger LET. Moreover, they exhibit similar physical characteristics to carbon, oxygen, and neon ions, which are all used in heavy ion therapy. However, they demonstrate a sharper lateral penumbra with a lower radiobiological absence of certainties and lack the degradation of variations in dose distributions caused by excessive fragmenting of heavier-ion beams, especially at greater depths of penetration. In this context, the status and the prospective advancements of helium ion therapy are examined by investigating ionization, recoil, and lateral scattering values using MC TRIM algorithms in mandible plate phantoms designed from both tissue and previously studied biomaterials, providing an overview for dental cancer treatment. An average difference of 1.9% in the Bragg peak positions and 0.211 mm in lateral scattering was observed in both phantoms. Therefore, it is suggested that the 4He ion beam can be used in the treatment of mandibular tumors, and experimental research is recommended using the proposed biomaterial mandible plate phantom.

Rhabdomyosarcoma With FUS::TFCP2 Fusion in the Mandible: A Rare Aggressive Subtype, but Can Be Misdiagnosed as Ossifying Fibroma.

Rhabdomyosarcoma (RMS) with TFCP2 rearrangement has been identified recently. This entity has a distinctive clinicopathologic features: a rapidly aggressive clinical course, a preference for the craniofacial bones, a spindle and epithelioid histomorphology, and positive immunohistochemistry for epithelial markers, ALK, and myogenic markers. RMS with TFCP2 rearrangement is rare and may be misdiagnosed as other spindle cell tumors. Here, we report a case of this entity arising in the mandible, which was initially diagnosed as ossifying fibroma in primary tumor in another hospital. A 26-year-old man presented with a recurred mass in the mandible for 1 month after the operation of mandibular tumor. The first excisional specimen was initially diagnosed as ossifying fibroma in another hospital. Histopathologic examination revealed the tumor with a hybrid spindle cell and epithelioid cytomorphology, spindle cells and spindle-to-epithelioid cells with eosinophilic and rich cytoplasm, with high-grade features, prominent nucleoli and some atypical mitosis. Immunohistochemical analysis revealed positivity for desmin, MYOD1, pan-keratin, ALK (5A4), ALK (D5F3). Based on the morphology and immunophenotype, molecular studies were performed, which revealed a FUS::TFCP2 fusion transcript, confirming the diagnosis of Rhabdomyosarcoma with FUS::TFCP2 fusion. Making a correct diagnosis is primarily dependent on awareness by the pathologist of this rare subtype of RMS and careful histopathological evaluation, supported by immunohistochemical and molecular analysis, to avoid potential diagnostic pitfalls.

A multi-disciplinary team approach to pediatric malignant mandibular tumors

Mandibular tumors in the pediatric population are rare. These malignancies are variable in their histology, and combined with their rarity, has made it difficult to describe their clinical course, and treatment guidelines. The aim of this paper is to describe the experience of Boston Children's Hospital, a pediatric tertiary referral center, with treating malignant mandibular malignancies, as well as provide multi-disciplinary team approach in managing this clinical entity. A retrospective search was performed for mandibular malignancies in pediatric patients between 1995 and 2020 via the pathological database at Boston Children's Hospital. Only patients with malignant solid mandibular neoplasms were included, leaving 15 patients for final analysis. The median age at presentation was 10.1±10.3 years. Nine of 15 patients (60%) presented with jaw mass which was the most common clinical presentation. The most commonly identified histological diagnosis was rhabdomayosarcoma and osteosarcoma (n=4, 26% each). A mandibulectomy was performed in 12 (80%) cases. Reconstruction of the mandible was performed using a fibular free flap in 6 (40%) cases, and a plate in 3 (20%) cases. Mean follow-up was 4.6±4.9 years. Malignant tumors most commonly present with a jaw mass, however asymptomatic and incidental presentations follow closely and pathologies can vary greatly. Surgical resection and reconstruction is often indicated, multidisciplinary tumor board review is required to determine when children are best treated with neo-/adjuvant treatment with chemo- and radiotherapy.