Retromolar Trigone Research Articles

Submental flap: A reconstructive option in head and neck surgery

ObjectiveThe submental flap is a fasciocutaneous flap used in head and neck reconstruction. The aim of this study was to share the indications and outcomes of submental flap reconstruction based on our experience. MethodsA retrospective descriptive study was conducted on a group of 14 patients who underwent reconstructive surgery of the orofacial region with the submental flap. All reconstructions were performed following oncologic resections. ResultsThe submental flap was employed for the reconstruction of mobile tongue in 5 cases, maxilla and hard palate in 4 cases, cheek in 2 cases, floor of the mouth in 1 case, retromolar trigone in 1 case and oropharyngeal defects in 1 case. Satisfactory oral cavity opening was achieved in all cases. No transfer of metastatic lymph nodes to the recipient area was detected in this study. ConclusionsThe submental flap significantly shortens the surgical time compared to microvascular flaps. In our experience, the necessity for neck lymph node surgery does not preclude the use of the submental flap. Meticulous dissection of the flap greatly reduces the risk of potential transfer of tumours through the flap to the recipient area.

Pleomorphic Adenoma of Hard Palate: A Case Report

Salivary gland tumors are rare and account for only 2-3% of head and neck tumors, most of which are benign. Pleomorphic adenoma is the most common salivary gland tumor. This tumor mostly involves the parotid gland. However, if it occurs in the minor salivary glands, the palate is the most common site, followed by the lips, buccal mucosa, floor of the mouth, tongue, tonsils, pharynx, retromolar trigone, and gingiva. It usually presents as a slow-growing, painless submucosal mass on the hard palate. For a definitive diagnosis, it is necessary to perform a preoperative core biopsy for histopathological examination and Computed Tomography to evaluate the erosion of the hard palate and the severity of the erosion. We aim to describe the clinical, and radiological features, as well as the management of this rare localization of pleomorphic adenoma. In this case, a 30-year-old Iranian male patient with pleomorphic adenoma of the small salivary glands of the hard palate with the chief complaint of painless swelling on the left side of the palate for the past 5 years was reported. Although pleomorphic adenoma is a common entity, it is still a challenging tumor for pathologists, radiologists and surgeons. Various histological and topographic features make this tumor unique. Computed tomography and correct histopathological diagnosis are necessary to establish an appropriate surgical treatment, to achieve complete removal of the lesion through extensive local excision with periosteum or bone removal if involved to prevent recurrence.

Histologic spectrum and outcome of Human papillomavirus (HPV)-associated oral cavity squamous cell carcinoma: a single center experience and a survey of The Cancer Genome Atlas (TGCA) cohort.

While high-risk human papillomavirus (HPV) serves as an essential pathogen and an important prognostic and predictive biomarker for oropharyngeal squamous cell carcinoma, it occurs at low frequency (2.2-6%) in oral cavity squamous cell carcinoma (OCSCC). To date, the pathologic features of HPV-associated OCSCC (HPV( +)-OCSCC) have been sparsely reported and its prognosis is not well-defined. We herein described detailed clinicopathologic features and outcomes of a retrospective series of 27 HPV( +)-OCSCC, including 13 from Memorial Sloan Kettering Cancer Center (MSKCC) and 14 from The Cancer Genomic Atlas program (TCGA). The frequency of HPV positivity in OCSCC was 0.7% in MSKCC cohort and 4.9% in TCGA cohort. Although HPV( +)-OCSCC was predominantly non-keratinizing (in 81%) with various degree of maturation, its histologic spectrum was expanded to include keratinizing subtype (19%), adenosquamous carcinoma (7%), and papillary architecture (subtype, 7%). HPV( +)-OCSCC predominantly affected male patients (male:female ratio = 12.5:1) and (ex) smokers (77%). It might occur in mandibular mucosa, floor of mouth, tongue, retromolar trigone, buccal mucosa, maxillary mucosa, or hard palate. In oral cavity, positivity of HPV by RNA in situ hybridization was required, and p16 immunohistochemistry alone was insufficient to confirm the HPV + status. The positive predictive value of p16 immunopositivity in detecting HPV infection was 68%. HPV-positivity did not appear to affect outcomes, including disease specific survival and progression free survival in OCSCC.

Mandibular Ameloblastoma: A Reported Case

Ameloblastoma is a benign aggressive odontogenic tumor which requires early diagnosis and appropriate treatment. It commonly affects the mandible and radical surgery is the gold standard treatment. We report the case of a patient with ameloblastoma in extremely advanced phase affecting the retromolar trigone who was treated with concomitant chemoradiation therapy. Mandibular ameloblastoma is not well documented in the literature. It is usually diagnosed at the later stage when optimal surgery cannot be performed. This case study aimed to demonstrate that radiation therapy is a real therapeutic alternative in the treatment of advanced and inoperable forms of ameloblastoma.

Immunohistochemical Expression of Bcl-2, E-cadherin, CD34 and CD105 in Basaloid Squamous Cell Carcinoma - An In Vitro Study

Abstract Introduction: Basaloid squamous cell carcinoma (BSCC) is a rare aggressive variant of oral squamous cell carcinoma (OSCC) with a high propensity for distant metastasis. In this article, we present clinicopathological and survival data of eight cases of BSCC and further analyse the behaviour of these tumours with the help of E-cadherin, CD34, CD105 and B cell lymphoma-2 (Bcl-2) immunoexpression. Materials and Methods: Histopathologically confirmed cases of BSCC were retrieved from the department archives. Clinicopathological details and survival data of these patients were collected. Immunohistochemical analysis was performed with Bcl-2, E-cadherin, CD34 and CD105 on these cases and compared with different grades of OSCC (well differentiated, moderately differentiated and poorly differentiated). The statistical analysis was done using IBM SPSS software version 23. Results: BSCC was seen commonly in males of age group 49–71 years and predominantly reported in the retromolar trigone. Bcl-2 expression was significantly lower in BSCCs when compared to the conventional OSCC groups (P < 0.05). E-cadherin expression showed no significant difference between BSCC and well-differentiated OSCC group (P = 0.487). The overall mean survival for patients with BSCC was 6.37 months. Discussion: BSCCs of the oral cavity show increased CD105, CD34, E-cadherin and low Bcl-2 labelling. A substantial relationship between the tumour neo-angiogenesis, collective cell migration and apoptotic property could be related to the aggressive nature of this tumour and its poor overall survival rate. BSCCs are common in middle to older aged male and show increased expression of CD105, CD34 and E-cadherin.

A Morphometric Study of the Retromolar Fossa and the Incidence of the Retromolar Foramen in Dry Human Mandibles.

The mandible is the largest and strongest facial bone which plays a crucial role for various surgeries and diagnostic imaging. The retromolar fossa, located behind the third molar socket on each side, was observed for morphometry of anterior, medial, and posterior borders. The present study aimed to assess the retromolar fossa and the presence of retromolar foramen. This cross-sectional study was conducted on 30 dry mandibles of adult humans of unknown sex; morphometry of retromolar foramen was done using three parameters: anteriorly, laterally, and posteroinferiorly. Dimensions of the retromolar trigone were seen with notable differences between the right and left sides. Dimensions of the anterior border had a mean of 12.34±1.175 mm on the right side and 12.56±1.46 mm on the left side. The mean of the medial border of the trigone on the right side was 20.23±2.84 mm and on the left side was 21.48±2.57 mm. The lateral border had the mean value of 18.33±3.56 mm and 19.21±3.93 mm on the right and left sides respectively. The P-value of the medial border was found to be statistically significant (P=0.02). Retromolar foramen was observed in 60% of mandibles; six were unilateral and 12 were bilateral. These foramina were closer to the anterior border of the retromolar trigone as compared to the anterior border of the ramus and lingula of the mandibles. The awareness of these findings is crucial for the prevention of complications, such as neurovascular damage, during surgeries in this region. This knowledge is particularly relevant in addressing oral pathologies and extracting third molars, contributing to improved surgical outcomes and patient safety.

Assessment of Pattern of Cervical Lymph Node Metastasis in Squamous Cell Carcinoma of Oral Cavity

Objective: Cervical lymph node involvement is crucial for prognostic factor for oral squamous cell carcinomas, and understanding nodal metastasis pattern is essential for optimal neck dissection, oncological control, and minimizing morbidity. This study reviews nodal involvement and skip metastasis in 316 oral SCC patients to determine the extent of neck dissection. Methods: The retrospective study analysed 316 patients with oral cancer diagnosed between 2017 and 2020, including those with primary oral cavity cancer who underwent neck dissection. A comprehensive assessment of patient data was used to determine the extent and size of the lesion and lymph node involvement. Preoperative staging was confirmed using various imaging techniques, including OPG, CT MRI, and biopsies. Histological examination results were used to categorize carcinomas based on differentiation levels and to identify nodal involvement patterns. Results: The most common subsite for 316 patients was the tongue (62%), followed by the buccal mucosa (19%), lower alveolus (10.2%), hard palate (3.2%), retro molar trigone (2.8%), floor of the mouth (1.6%), upper alveolus (0.9%), and lower lip (0.3%). Nodal metastasis were more common in Levels II and Ib, with less involvement in Level III and beyond. Tumour with a DOI greater than 10 mm showed higher nodal metastasis frequency, with an increased occurrence in Levels IA, IB, II, III, and IV. Conclusion: Nodal metastasis in oral cancer are common in Levels II and Ib, with variations based on subsite. Alveolus and buccal mucosa malignancies involve fewer lymph nodes beyond Level III, while tongue malignancies show greater involvement in lower levels Level IV involvement is more frequent with greater DOI, and skip metastasis are rare.

Oral Reconstruction with Locoregional Flaps after Cancer Ablation: A Systematic Review of the Literature.

Introduction: The planning of oral reconstruction after tumor resection is a pivotal point for head and neck surgeons. It is mandatory to consider two aspects: the size of the surgical defect and the complexity of the oral cavity as an anatomical region. We offer a review of the literature that focuses on four types of locoregional flaps that can be profitably used for such reconstruction: infrahyoid (IF), nasolabial (NF), platysma (PF), and submental (SF). Methods: The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This systematic review was carried out according to the PICOS acronym through a comprehensive electronic search on PubMed/MEDLINE, Cochrane Library, and Google Scholar databases. For each selected article, we extrapolated eight main parameters, of which all mean values were compared through an ANOVA test. The dimensions of the oral defects were referred to as "small" (<7 cm2), "medium" (7-50 cm2), or "large" (>50 cm2). Results: A total of 139 articles were selected with a total of 5898 patients. The mean ages for each type of flap were not statistically significant (p = 0.30, p > 0.05). Seven sublocations of oral defects were reported: The most common was the tongue (2003 [34.0%] patients), followed by the floor of the mouth (1786 [30.4%]), buccal mucosa (981 [16.6%]), cheek (422 [7.2%]), hard palate (302 [5.1%]), alveolar ridge (217 [3.7%]), and retromolar trigone (187 [3.2%]). The defects were mainly medium-sized (4507 [76.4%] patients), and fewer were small-sized (1056 [17.9%]) or large-sized (335 [5.7%]). Complications were noted, the most frequent of which was flap necrosis, seen in 0.57% of cases. The functional and esthetical results were mainly positive. Conclusions: Locoregional flaps represent a good alternative in medium-sized defects as well as a fairly good alternative in small- and large-sized defects when other options are ruled out.

A case report: Cellular (Myoepithelial Rich) pleomorphic adenoma of hard palate: A diagnostic dilemma

Salivary gland tumors account for &amp;#60;3% of the head and neck tumors. Pleomorphic Adenoma is the most common salivary gland tumor which constitutes for about 60% of all major and minor salivary gland tumors. Among the minor salivary glands tumors, pleomorphic adenoma makes about 70% and the most common site in the oral cavity is the palatal area, followed by the lip, buccal mucosa, floor of mouth, tongue, tonsil, pharynx, retromolar trigone, and gingiva. Females are more commonly affected than males. Pleomorphic adenoma of the hard palate presents as a painless firm submucosal mass without tenderness, ulceration, or surrounding inflammation; usually lacking a well-defined capsule and frequently involves periosteum or bone.These tumors are located laterally, and they rarely cross the midline.

Surgical Technique for Compartmental Resection of T4b Gingivobuccal Cancer.

Management of advanced gingivo-buccal complex cancers involving the masticatory space (T4b) is often managed by compartment resection. Theoncological safety of the procedure is now clearly established. Based on the origin and epicenter of the tumor there are two classes of compartmental resection. Those tumors arising from the tuberosity of themaxilla and/or upper gingival sulcus region; the resection involves the tumor, posterior maxilla, and the ipsilateral infratemporal fossa. These tumors can be resected by mandibulotomy approach, preserving the mandible. This constitutes class-1 infratemporal fossa resection. The class-2 infratemporal fossa resection is applied for those tumors arising from the retromolar trigone and/or lower gingivo-buccal sulcus region. In this class, the mandible and often the overlying cheek skin needs to besacrificed, in addition to the contents of theinfratemporal fossa and the posterior maxilla. Both the classes of resections are carried out in an orderly fashion following well-defined steps. These sequential steps maximize the exposure of inaccessible structures, enables protection of critical structures as well as minimizes blood loss. This manuscript describes the surgical steps for the two classes of compartmental resection of theinfratemporal fossa for advanced gingivo-buccal complex cancers involving themasticatory space.

Vascular Leiomyoma of oral cavity: A case report in young male patient

Abstract Vascular Leiomyoma of the oral cavity is an uncommon benign soft tissue neoplasia arising from the tunica media of the smooth muscle cells. We reported a rare case of Vascular Leiomyoma involving the retromolar trigone area of a young man. A 24-year-old male presented with a slowly growing mass in the retromolar area, which was associated with pain and difficulty in opening of mouth and eating and drinking. A punch biopsy was taken and sent for histopathological examination which revealed a benign angiomatous lesion. The mass was excised, and the adjoining area was curetted. Histopathological examination confirmed the diagnosis of Vascular Leiomyoma. The immunohistochemistry of cells shows: alpha-smooth muscle (+); vimentin (+), Desmin, actin (+), and S100 (−). Angioleiomyomas are benign lesions, but malignant transformation is a possibility so careful histologic inspection is necessary to distinguish these lesions from their malignant counterpart.

Mutational analysis of BRAFV600E in a case of sialadenoma papilliferum of oral cavity

Abstract This case report presents a rare benign salivary gland tumour called sialadenoma papilliferum. It comprises 3 to 5% of head and neck tumours and about 1% of all minor salivary gland tumours. The focus is on discussing the BRAFV600E mutation analysis and exploring its clinical implications, along with delving into the histopathological differentials. We documented a 73-year-old male, who had a white patch in the left retromolar trigone region for 6 months. The tumour was excised with a clinical diagnosis of verrucous lesion. Microscopic examination revealed exophytic hyperplastic parakeratotic stratified squamous epithelium and endophytic ductal papillary proliferation. The BRAFV600E mutation was present in the patient. Subsequent regular follow-ups were conducted, revealing no recurrence of the condition. This case underscores the pivotal role of BRAFV600E analysis as an invaluable diagnostic tool when confronted with the intricacies of intraoral salivary gland neoplasms.

An unusual case of peripheral osteoma in a young patient

Osteoma is a benign osteogenic neoplasm characterized by gradual growth. Commonly, it manifests in the craniofacial region, marked by the proliferation of compact and/or cancellous bone. Despite its frequent occurrence, peripheral osteoma’s precise etiology and pathogenesis remain unknown. Post-surgical excision recurrence is rare, and malignant transformation has yet to be documented. This study aims to detail an unusual case of an 11-year-old male patient presenting with a solitary peripheral osteoma in the right retromolar trigone region, a previously unreported site. The patient was initially asymptomatic, but after one month, the lesion induced facial asymmetry and discomfort while chewing. Successful surgical intervention resulted in the lesion's removal, and after 1 year of monitoring, no signs of recurrence were observed. This paper also highlights the peripheral osteoma’s clinical, radiographic, surgical, and histopathological features, as well as its differential diagnoses.

Trotter Procedure with Harmonic Scalpel : A Unique Approach to Mucoepidermoid Carcinoma of Tongue Base Revisited.

Mucoepidermoid carcinoma (MEC) is a malignant locally invasive tumour of salivary glands, presumed to arise from reserve cells of salivary gland ducts. It accounts approximately 35% of all malignancies of major and minor salivary glands [1]. MEC arising in minor salivary glands can be located in different areas such as palate, retromolar trigone, floor of mouth, buccal mucosa, lips and tongue. MEC of tongue base are not common but they constitute around 50% of malignant lesions of salivary glands in this region. It presents in fifth and sixth decades of life mostly [1]. We present a rare case of 29 year old woman with low grade mucoepidermoid carcinoma of base of tongue operated by the Trotter procedure with harmonic scalpel - median labio-mandibular glossotomy approach. It's an interesting approach first described by William Trotter in 1920s. It's used by head and neck surgeons for accessing tongue base lesions, pharyngeal wall and cervical spine.

The Trans-facial Approach for Simultaneous Resection and Reconstruction of Retromolar Trigone Tumors: A Pilot Study

IntroductionEarly retromolar trigone (RMT) lesions are difficult to access and free tissue transfer is often an overkill for such small lesions. The aim was to devise a novel surgical approach that would aid the resection without raising a cheek flap and simultaneously provide a local reconstructive option for small lesions in the RMT.MethodologyThis study was to demonstrate the outcomes of the “trans-facial” approach used to simultaneously access and reconstruct small RMT tumors through an islanded nasolabial flap. Patients with histologically proven squamous cell carcinoma of RMT requiring surgery were included from January 2021 to September 2022. Case selection was done based on the location of the disease and its size (cT1/T2). All needed bone and soft tissue resection via per oral trans-facial approach, along with an ipsilateral neck dissection. The technique is described along with their post-operative and pathologic outcomes.ResultsOut of the eight patients included in this study, six underwent a bi-alveolar marginal resection and reconstructed using the trans-facial approach. No major complications were noted in the post-operative period. 50% were pT1 tumors and 75% were pN0 status. One patient had a close margin; while, the others had adequate resection margins. All patients were followed up for a median of 18 months with a locoregionally controlled status.ConclusionThe trans-facial approach can be a suitable option with a reasonable oncologic outcome to address small RMT lesions.

Oncological Safety and Feasibility of Posterior Marginal Mandibulectomy vis-à-vis Anterior Marginal Mandibulectomy in Oral Cancers

The surgical management of retromolar trigone cancer (RTC) is an area of contention regarding the extent of bony resection. We aim to evaluate the oncological safety and feasibility of posterior marginal mandibulectomy (PMM) for RTC. We analyzed the clinical records of 98 patients with squamous cell carcinoma managed surgically using marginal mandibulectomy during 2014 to 2017, in which anterior segment mandibulectomy (AMM) and PMM were done in 56 and 42 patients, respectively. The median follow-up time was 44.4 months (95% confidence interval [CI] 42.3, 49.5) and the overall survival rate was 93.9% (95% CI 89.4–98.8%). The local recurrence rate was 19.6 and 18.3 % in PMM and AMM (p = 0.854). In the PMM group, osteoradionecrosis (ORN) was detected in two patients (4.3%) and fractures in one (2.1%) patient, while the AMM group neither had fracture nor ORN till the latest follow-up. The study results suggest that PMM is an oncological safe and adequate procedure for RTC.

Location of mandibular foramen in dry mandibles in relation to various anatomical landmarks

To localize the mandibular foramen in dry mandibles of adult and old age groups of South Indian origin by estimating its average distance from different anatomical landmarks and to provide a specific and precise site for inferior alveolar nerve block. : A total of 51 mandibles were taken for the study and the distance between the mandibular foramen and the various anatomical landmarks were measured using a digital vernier caliper. Presence of accessory mandibular foramen was observed and recorded. Difference between the sides and the correlation between the gonial angle and various distances were carried out.:Distance of mandibular foramen from anterior border was 16.41±2.44 mm and 16.85±2.55 mm, from posterior border was 10.28±2.08 mm and 10.13±2.02 mm, from mandibular incisure 22.5±3.13mm and 21.9±3.08mm, from mandibular base 23.72±3.37 mm and 24.5±3.27 mm, from third molar 15.27±11.99 mm and 16.85±11.60 mm, from apex of retro molar trigone 18.28±3.02 mm and 19.79±3.18 mm on right and left side respectively. There was no significant difference between the measurements of right and left sides. The measurements had a negative association with gonial angle. Accessory foramina were found to be present in 21and 23 mandibles on right and left side respectively.:Precise localization of mandibular foramen is clinically very important to achieve effective inferior alveolar nerve block prior to dental surgeries in the lower jaw. The present study establishes the presence of bilateral symmetry in the position of mandibular foramen with respect to various anatomical landmarks and the utility of gonial angle in localizing the mandibular foramen.

The Occurrence of a Rare Mandibular Retromolar Triangle Schwannoma and Its Differentiation from Other Rare and Atypical Oral Cavity Tumours

The Occurrence of a Rare Mandibular Retromolar Triangle Schwannoma and Its Differentiation from Other Rare and Atypical Oral Cavity Tumours

Clinical characters and survival outcomes in primary squamous cell carcinoma of the retromolar trigone

BackgroundsTo better study the clinical characters and survival outcomes associated with primary squamous cell carcinoma of the retromolar trigone (primary SCC RMT), this study was analyzed through the SEER database to determine the factors. MethodThe SEER database was searched for patients with primary SCC RMT between 2000 and 2018. Data on age, sex, race, marital status, radiotherapy, chemotherapy, etc. of the patients were collected and analyzed. R software was used to create prognostic nomograms to forecast Cancer-specific survival likelihood. The consistency index, calibration curve, and receiver operating characters curve evaluated the prediction abilities of the nomogram. Result3128 cases of primary SCC RMT were screened. Patients were randomly divided into 465 and 208 on a 7:3 basis. Univariate Cox regression showed that age, marital status, radiotherapy, chemotherapy, surgery, lymph node surgery, T-stage, N-stage, and M-stage were primary SCC RMT correlates, and multivariate Cox regression revealed that age, Surgery, T-stage, and N-stage were independent risk factors for primary SCC RMT. In addition, calibration curves showed good agreement between nomogram predictions and actual 1-, 3-, and 5-year CSS incidence in both the primary and the validation cohorts. ConclusionsBy analyzing the SEER database, we constructed a nomogram of the factors associated with primary SCC RMT and a corresponding validated analytical model, in the hope that it can better help guide clinical treatment.

Dosimetric validation of intensity-modulated bolus electron conformal therapy planning and delivery using an anthropomorphic cylindrical head phantom.

This work investigated the dosimetric accuracy of the intensity-modulated bolus electron conformal therapy (IM-BECT) planning and delivery process using the decimal ElectronRT (eRT) treatment planning system. An IM-BECT treatment plan was designed using eRT for a cylindrical, anthropomorphic retromolar trigone phantom. Treatment planning involved specification of beam parameters and design of a variable thickness wax bolus and Passive Radiotherapy Intensity Modulator for Electrons (PRIME) device, which was comprised of 33 tungsten island blocks of discrete diameters from 0.158 to 0.223cm (Intensity Reduction Factors from 0.937 to 0.875, respectively) inside a 10.1×6.7 cm2 copper cutout. For comparison of calculation accuracy, a BECT plan was generated by copying the IM-BECT plan and removing the intensity modulation. For both plans, a 16 MeV electron beam was used with 104.7cm source-to-surface distance to bolus. In-phantom TLD-100 measurements (N=47) were compared with both eRT planned dose distributions, which used the pencil beam redefinition algorithm with modifications for passive electron intensity modulation (IM-PBRA). Dose difference and distance to agreement (DTA) metrics were computed for each measurement point. Comparison of measured dose distributions with planned dose distributions yielded dose differences (calculated minus measured) characterized by a mean and standard deviation of -0.36%±1.64% for the IM-BECT plan, which was similar to -0.36%±1.90% for the BECT plan. All dose measurements were within 5% of the planned dose distribution, with both the BECT and IM-BECT measurement sets having 46/47 (97.8%) points within 3% or within 3mm of the respective treatment plans. It was found that the IM-BECT treatment plan generated using eRT was sufficiently accurate for clinical use when compared to TLD measurements in a cylindrical, anthropomorphic phantom, and was similarly accurate to the BECT treatment plan in the same phantom.