Schwannoma base of Tongue - Case Report with a Novel Reconstruction Technique

INTRODUCTION

Schwannomas are benign, slow-growing well-encapsulated neoplasms arising from Schwann cells of nerve sheaths. Oral cavity schwannomas are very rare with an incidence less than 1%. The posterior third of the tongue is not frequently involved.

CASE REPORT

We report a rare case of a large tongue base schwannoma in a 44 year old female managed surgically by lateral pharyngotomy approach. A novel reconstruction method involving the use of submental flap is described for the functional reconstruction of the defect.

CONCLUSION

Being a rare tumor, schwannoma should not be missed in the differential diagnosis of tongue base tumors. Complete surgical resection is the treatment of choice with recurrence being very rare.

Anatomical landscape of oral squamous cell carcinoma: A single cancer center study in UAE

Objectives

This study aimed to present demographic and clinicopathological aspects of OSCC identified in Pathology service in the UAE over a 13-year period and compare these findings to a cohort of 523 cases of Head and neck squamous cell carcinoma using the Cancer Genome Atlas's cBioPortal database (http://cbioportal.org).

Material and methods

Histological examination of all hematoxylin and eosin-stained slides and assessment of all demographic and clinical information from laboratory records were performed on all OSCC diagnosed between 2005 and 2018.

Results

Males made up 71.4% of the sample of 231 OSCCs that were evaluated. The patients' average age was 55.38 years. The two most prevalent afflicted sites were the anterior two-thirds of the tongue (57.6%) and the cheek (28.1%). The most prevalent site among smokers were the floor of mouth, cheek, and jaw bones. There was a link between tumor size and numerous anatomical subsites that was shown to be highly significant. OSCC in the FOM was associated with a 25% mortality rate. Patients with OSCC of the anterior tongue and cheek had the best prognosis, with only 15.7% and 15.3% of patients dying during follow-up.

Conclusion

The present investigation found a correlation between the diverse clinicopathological characteristics of the various anatomical subsites in OSCC. Different anatomical subsites also displayed varying degrees of gene mutation.

Cribriform adenocarcinoma of the minor salivary glands: a case report

BACKGROUND

Polymorphous adenocarcinoma is the third most common malignant salivary gland tumor. Within polymorphous adenocarcinoma, cribriform adenocarcinoma of salivary glands is a rare subtype and resembles papillary thyroid carcinoma histopathologically. Diagnostically, cribriform adenocarcinoma of salivary glands is challenging for pathologists and surgeons alike as initial presentation and cytologic nuclear features can be easily confused with papillary thyroid carcinoma arising from a thyroglossal duct remnant or lingual thyroid.

CASE PRESENTATION

A healthy 64-year-old Caucasian woman presented to a community otolaryngologist with a 4-year history of progressive postnasal drip, globus sensation, and eventual dysphonia. Flexible fiberoptic laryngoscopy showed a large, smooth, vallecular lesion filling the oropharynx. Computed tomography imaging of the neck showed a rounded heterogeneous mass centered within the right aspect of the oropharynx measuring 4.2 × 4.4 × 4.5 cm. Fine needle aspiration biopsy was suspicious for papillary carcinoma due to microscopic findings of malignant cells, nuclear grooves, and a powdery chromatin pattern. In the operating room, the tumor was resected en bloc using a lateral pharyngotomy approach with partial resection of the right lateral hyoid. A limited cervical lymphadenectomy was performed to facilitate the lateral pharyngotomy approach and two out of three lymph nodes demonstrated regional metastatic disease. Nuclear grooves, nuclear membrane notching, and occasional intranuclear pseudoinclusions were identified, which are overlapping histopathological characteristics of papillary thyroid carcinoma and cribriform adenocarcinoma of salivary glands. It was negative for thyroglobulin and thyroid transcription factor-1, which was in keeping with cribriform adenocarcinoma of salivary glands rather than papillary thyroid carcinoma.

CONCLUSION

It is difficult to distinguish cribriform adenocarcinoma of salivary glands from papillary thyroid carcinoma solely by cytology, and the distinct characteristics of regional lymph node metastasis coupled with nuanced histologic differences should be emphasized in the evaluation of patients presenting with neck lymphadenopathy and an unknown primary or tongue mass. If sufficient fine needle aspiration biopsy material is available, thyroid transcription factor-1, thyroglobulin, or molecular testing may prove useful in differentiating cribriform adenocarcinoma of salivary glands from papillary thyroid carcinoma. A misdiagnosis of papillary thyroid carcinoma may lead to inappropriate treatment including unnecessary thyroidectomy. Therefore, it is critical for both pathologists and surgeons to be aware of this uncommon entity to avoid misdiagnosis and subsequent mismanagement.

Practising transoral robotic surgery in a middle-income country: surgical outcomes and early challenges

Transoral robotic surgery is a minimally invasive surgical technique that recently debuted in Malaysia. However, there are concerns over its cost, practicality, and feasibility in local settings. Our study aims to evaluate the surgical outcomes of transoral robotic surgery and discuss its learning curves. The clinical records of all patients who underwent transoral robotic surgery in a university hospital were reviewed. 25 patients were identified with a mean age of 43.9 years. The commonest indication was obstructive sleep apnoea (OSA) (76%), followed by base of tongue carcinoma (16%), recurrent tonsilitis and Wharton's duct cyst (4% each). For excision of tongue base in obstructive sleep apnoea without epiglottectomy, the mean operating time was 2.3(±0.9) hours with an average of 2.8(±0.4) days of hospital stay. The success rate for OSA surgery was seen in 78.9% of cases. The mean operating time for transoral excision of tongue base carcinoma was 4.3(±2.5) hours, whereas the mean hospital stay was 9(±3.6) days. All surgical margins were cleared with no recurrence except for one patient. The recurrent tumour was successfully excised via transoral robotic surgery, and he remained disease free after one year. The most frequent post-operative complaints were dysphagia, post-nasal drip, and hypogeusia. Transoral robotic surgery in Malaysia is in the commencement phase, where some pitfalls are expected. Opportunities should be given for more surgeons to acquire this technique so that minimally invasive surgery for head and neck diseases is readily available for patients in middle-income countries.

Behavioral Interventions Targeting Base of Tongue to Posterior Pharyngeal Wall Approximation: A Scoping Review

Pharyngeal pressure generated by approximation of the base of tongue to the posterior pharyngeal wall (BOT-PPW approximation) is critical for efficient pharyngeal bolus passage and is a frequent goal of dysphagia management. This scoping review evaluated behavioral interventions available to improve BOT-PPW approximation. We searched MEDLINE, CINAHL, Ovid Emcare, Web of Science, SCOPUS, and ProQuest for studies that met the following criteria: (i) behavioral interventions targeting BOT-PPW approximation, which (ii) were assessed using BOT-PPW-specific outcome measures, and (iiia) performed over a period of time (Review Part 1) or (iiib) studied immediate effects (Review Part 2). Study quality was rated using the GRADE framework. Data were extracted and synthesized into dominant themes. Of the 150 studies originally identified, three examined long-term effects (two single cases studies of individuals with dysphagia, and a third study evaluating effortful swallowing in healthy individuals). BOT-PPW approximation only increased in the two single case studies. Twenty-one studies evaluating immediate effects were categorized as follows: (1) effortful swallowing, (2) Mendelsohn maneuver, (3) tongue-hold maneuver, (4) super supraglottic swallowing maneuver, and (5) non-swallowing exercises. Across all studies, varying levels of success in increasing BOT-PPW approximation were reported. Four of 21 immediate effects studies evaluated patients with demonstrated swallowing impairment, whereas 17 studies evaluated healthy adults. Quality assessment revealed low strength of the existing evidence base. The evidence base for rehabilitative interventions targeting BOT-PPW approximation is severely limited and translation is hindered by small sample sizes and methodological limitations. Further clinical research is warranted.

Base of tongue metastasis of cutaneous malignant melanoma with rhabdoid and neuroendocrine features: Report of a rare case and review of the literature

Metastatic malignant melanoma (MM) represents a highly aggressive cancer associated with overall poor prognosis. Various anatomic sites can be affected, including the oral cavity and the oropharynx. It may mimic other entities by assuming a variety of clinical appearances and exhibiting a plethora of microscopic variations. Herein, we present a case of a 63-year-old male with a MM metastasizing to the base of tongue, which developed 5 years after the original diagnosis and treatment of cutaneous MM of the chest and heralded its relapse; subsequently, neurological symptoms developed as a result of metastasis to the brain. Diagnostic challenges were encountered, as the tongue lesion clinically masqueraded as a pedunculated reactive lesion and microscopically displayed unusual rhabdoid and neuroendocrine features. Tumor cells expressed S-100, HMB-45, Melan-A, and SOX-10, while most cells with rhabdoid morphology were also positive for myogenin and Myo-D1. Chromogranin and synaptophysin positivity was further noticed in a subset of cells, suggestive of focal neuroendocrine differentiation. Molecular investigation revealed mutations for the BRAF V600E gene. Divergent differentiation of tumor cells may cause diagnostic pitfalls necessitating thorough immunohistochemical analysis. The presence of rhabdoid features and neuroendocrine differentiation are very uncommon, while their co-existence is extremely rare. Better characterization of such microscopic variations in MMs with evaluation of their potential biologic significance is warranted.

Effect of histopathological grade on treatment and survival in base of tongue adenocarcinoma

OBJECTIVES

The purpose of this study was to investigate survival differences between low-grade and high-grade base of tongue (BOT) adenocarcinoma by examining demographics, tumor characteristics, and treatment modalities.

METHODS

The National Cancer Database was queried for patients with BOT adenocarcinoma between 2004 and 2017. Univariate and multivariate analyses were performed for all cases of BOT adenocarcinoma. Subsequent analysis focused on low-grade (grade 1 and grade 2) and high-grade (grade 3 and grade 4) BOT adenocarcinoma.

RESULTS

A total of 286 patients with BOT adenocarcinoma were included in the main cohort and divided into low grade (n = 137) and high grade (n = 66). The 5-year overall survival for all patients, low-grade, and high-grade was 67%, 85%, and 58%, respectively. Prognostic factors associated with decreased survival for the main cohort include advanced age (hazard ratio [HR]: 1.04; 95% confidence interval [CI]: 1.02-1.06), non-white race (HR: 1.79; 95% CI: 1.04-3.25), public insurance (HR: 1.79; 95% CI: 1.02-3.14) and high-grade 3,4 (HR: 2.63; 95% CI: 1.51-4.56). The prognostic factor associated with increased survival for the main cohort was surgery (HR: 0.59; 95% CI: 0.36-0.96). Radiotherapy was associated with improved overall survival for high-grade BOT adenocarcinoma (HR: 0.09; 95% CI: 0.02-0.49) but not for low-grade BOT adenocarcinoma (HR: 0.93; 95% CI: 0.38-2.32).

CONCLUSIONS

This investigation is the largest to date analyzing the association of treatment modalities with overall survival in BOT adenocarcinoma. Surgery remains standard of treatment, particularly in low-grade cases, with radiotherapy offering additional survival benefit for high-grade BOT adenocarcinoma.

Metastatic HPV-Mediated Adenocarcinoma Arising from a Base of Tongue Primary: A Case Report with Cytomorphology and Molecular Findings with Review of the Literature

Human papillomavirus (HPV)-mediated squamous cell carcinomas of the oropharynx are common, however only rare cases of HPV-mediated oropharyngeal adenocarcinoma have been reported to date. In this report, we describe a 50 year old nonsmoking male who originally presented with an enlarging neck mass. Fine needle aspiration cytology confirmed an HPV-mediated adenocarcinoma. Subsequent surgery identified a 0.7 cm base of tongue primary HPV-mediated carcinoma with focal glandular differentiation and a 4.0 cm cystic lymph node metastasis demonstrating entirely glandular differentiation. Next generation sequencing of the metastasis detected a pathogenic NOTCH1 mutation.

Mixed HPV-related Neuroendocrine Carcinoma and HPV-related Squamous Cell Carcinoma of the Base of Tongue in a Patient With Incidental Identification of Synchronous Metastatic Papillary Thyroid Carcinoma

BACKGROUND

While it is not uncommon in patients with head and neck cancer to present with multiple metachronous primary neoplasms, rarely do these present as a singular mass composed of intertwined, histologically distinct malignant tumors. Sometimes referred to as collision tumors, these entities are poorly understood and only appear in a handful of case studies in the literature.

CASE REPORT

Here we present a 58-year-old male diagnosed with a human papillomavirus-related collision tumor consisting of oropharyngeal squamous cell carcinoma and small-cell neuroendocrine carcinoma, as well as an incidentally discovered metastatic thyroid papillary carcinoma, despite an unremarkable thyroid gland. The patient underwent transoral robotic base-of-tongue resection and partial pharyngectomy with selective neck dissection followed by chemoradiotherapy. At the 18-month follow-up the patient was doing well. His thyroid was normal and no recurrent or metastatic carcinoma was identified on the computed tomography and positron-emission tomography/computed tomography imaging findings.

CONCLUSION

To the best of our knowledge, this is the first such case in English literature. This case demonstrates the importance of tumor morphology and immunohistochemical testing in HPV-related oropharyngeal carcinomas, despite the overall good prognosis of such tumors, due to the possibility of synchronous or colliding primary neoplasms.

Base of Tongue Surgery for Obstructive Sleep Apnea in the Era of Neurostimulation

Retroglossal collapse is commonly seen in patients with obstructive sleep apnea. The role of upper airway stimulation surgery for these patients continues to evolve. However, base of tongue reduction surgery continues to have usefulness for appropriately selected patients with obstructive sleep apnea. Specific tongue base approaches may vary in response to patient and surgeon preferences and be used in multilevel surgery where appropriate. Key factors include patient age, willingness to undergo device implantation, and preferences for outpatient versus inpatient procedure, single procedure versus multiple, and tolerance for various procedure-specific postoperative restrictions and potential complications.

Hyalinizing Clear Cell Carcinoma: Base of Tongue

Hyalinizing clear cell carcinoma (HCCC) is a low grade, rare neoplasm originating from the minor salivary glands. It usually follows an indolent course and the main treatment modality is surgery. The prognosis of these tumours are good, hence it needs to be differentiated from other carcinomas with clear cells. Here we report a pathologically proven HCCC of the base of tongue.

Mucoepidermoid carcinoma of the oropharynx: a tumor type with a propensity for regional metastasis unrelated to histologic grade

The designation "mucoepidermoid tumor" is a historic one used in reference to a form of mucoepidermoid carcinoma (MEC) that was believed to be benign. This bygone notion was based on the observation that the vast majority of MECs arising from the intraoral minor salivary glands behave in a benign fashion, particularly when they do not exhibit high grade features. There has been a recent move to partition the oral vault into the oral cavity proper and the oropharynx based on awareness that these compartments are distinct, and that similar tumor types arising from these compartments may behave in dramatically different ways (e.g, oral cavity squamous cell carcinoma vs oropharyngeal squamous cell carcinoma). The pathology databases from 3 large academic medical centers were searched for cases of MECs arising in the oropharynx. Relevant clinical and pathological information was collected from the medical records. Twenty-five cases were identified. They were from 18 females (72%) and 7 males (28%), ranging in age from 31 to 88 years (median, 61). Twenty-two (88%) were classified as low (n = 12) or intermediate (n = 10) grade, and 3 (12%) as high grade. Most arose from the base of tongue (n = 24), but one arose from the lateral pharyngeal wall. The median tumor size was 2.0 cm. Nineteen patients underwent neck node dissections. Of these, 13 (68%) had histologically documented lymph node metastases. MECs that lacked high grade features were almost as likely to metastasize as those with high grade features (50% vs 66%, Fisher exact = 1). Of 3 metastases tested, 2 harbored the MAML2 gene fusion. MECs arising from the base of tongue are associated with an alarmingly high rate of nodal metastases. This behavior cannot be predicted by histologic grading or MAML2 status. The propensity to metastasize may to some degree reflect the unique microenvironment of the oropharynx.

Reader performance in the ultrasonographic evaluation of oropharyngeal carcinoma

OBJECTIVE

To examine reader performance in evaluating oropharyngeal anatomy on ultrasonography.

MATERIALS AND METHODS

Ultrasound images of the oropharynx comprising normal and malignant anatomic variants were organized into slideshows. Slideshows were administered to 6 readers blinded to participant tumor status and with varying experience reading oropharyngeal sonograms. A training slideshow oriented readers to images of the oropharynx with and without malignant lesions. Readers then evaluated images in a test slideshow for tumor presence and marked orthogonal long and short dimensions of the tumor. Results were analyzed for accuracy, sensitivity, specificity, inter-reader agreement, and measurement error relative to prospectively-identified reference measurements.

RESULTS

Eighty-seven percent of base of tongue (BOT) sonograms were identified correctly by a majority of readers. In identifying BOT tumors, median accuracy, sensitivity, specificity, and Fleiss's kappa were 79%, 73%, 85%, and 0.51, respectively. Median measurement error in the long and short axes for BOT tumors was -2.6% (range: -40% to 29%) and -2.6% (range: -56% to 156%), respectively. Eighty-four percent of palatine tonsil sonograms were identified correctly by a majority of readers. In identifying tonsil tumors, median accuracy, sensitivity, specificity, and Fleiss's kappa were 77%, 74%, 78%, and 0.41, respectively. Median measurement error in the long and short axes for tonsil tumors was 3.8% (range: -45% to 32%) and -6.5% (range: -83% to 42%), respectively.

CONCLUSIONS

Overall, US has clinically useful sensitivity for identification of oropharyngeal carcinoma among readers of diverse clinical backgrounds and experience. US may be useful for the evaluation of features such as tumor dimensions.

Adenoid cystic carcinoma of the base of tongue: A population-based study

BACKGROUND

The objective was to assess demographic and survival patterns in patients with adenoid cystic carcinoma of the base of tongue.

METHODS

Patients were extracted from the Surveillance, Epidemiology and End Results (SEER) database from 1973 through 2012 and were categorized by age, gender, race, historical stage A, and treatment. Incidence and survival were compared with Kaplan Meier curves and mortality hazard ratios.

RESULTS

A total of 216 patients were included. After adjusting for age, gender, race and tumor-directed treatment, patients over the age of 70years had a significantly increased mortality [HR=2.847, 95% CI (1.499, 5.404) p=0.0014]. Furthermore mortality among patients with distant disease was significantly increased [HR=2.474 95% CI (1.459, 4.195) p=0.00008].

CONCLUSION

By examining the largest collection of patients we have demonstrated that there is a significant difference in mortality based on both the age at diagnosis and in the setting of distant disease.

Continuing rise in oropharyngeal cancer in a high HPV prevalence area: A Danish population-based study from 2011 to 2014

BACKGROUND

Human papillomavirus (HPV) is a critical element in the rising incidence of oropharyngeal squamous cell carcinoma (OPSCC), although whether this trend will continue, and the types of HPV responsible, are currently unknown. We previously demonstrated an increased incidence of HPV-related OPSCC in the high HPV prevalence area of Eastern Denmark from 2000 to 2010. Therefore, we investigated if the incidence for OPSCC continued to rise, the association to HPV and putative HPV-types in Eastern Denmark from 2011 to 14. We then projected the expected incidence of OPSCC versus cervical cancer through to 2020.

PATIENTS AND METHODS

Patients with OPSCC (tonsillar squamous cell carcinoma [TSCC] and base of tongue squamous cell carcinoma [BSCC]) were identified via the Danish Head and Neck Cancer Group and the Danish Pathology Databank (n = 700). Tumours were re-reviewed and assessed using p16 immunohistochemistry, HPV DNA polymerase chain reaction (PCR), with genotyping by next generation sequencing.

RESULTS

Sixty-two percent (432/700) of tumours were HPV-positive (HPV+). The total incidence rate (per 100.000) for OPSCC increased from 4.0 in 2011 to 4.5 in 2014, primarily due to a rise in HPV+ TSCCs and HPV+ BSCCs, although numbers of HPV-negative (HPV-) OPSCC also increased during the study period. The majority of HPV+ tumours were HPV16 DNA positive (86%), but we also identified HPV33 DNA (6%), HPV35 DNA (4%) and others (3%), including HPV18, 26, 31, 45, 56, 58, 59 and HPV67.

CONCLUSION

An increasing incidence of OPSCC is driven primarily by HPV+ OPSCC. Sixty-two percent of tumours were HPV+, which is a high-prevalence, although the lower number of HPV- cases has yet to stabilise. HPV16 was the predominant genotype, although a significant proportion (14%) was of another genotype. Our projections suggest that the number of HPV+ OPSCC will exceed that of cervical cancer in 2016 in Eastern Denmark.

Transoral Robotic Partial Glossectomy and Supraglottoplasty for Obstructive Sleep Apnea

The standard treatment for patients with obstructive sleep apnea syndrome is positive airway pressure (PAP) therapy. However, when PAP therapy fails, surgery may be an option to alleviate the obstruction. The base of tongue plays an important role in this obstruction, and addressing the tongue base surgically can be a challenge for the head and neck surgeon. Transoral robotic surgery (TORS) using the da Vinci Surgical System provides a safe and effective way to approach and manage the base of tongue and supraglottis. Advantages of TORS include wide-field high-definition 3-D visualization, precise instrumentation, and when compared with open procedures, less operative time, quicker recovery, no external scars, and comparable tissue resection.

Transoral robotic surgery for the management of obstructive sleep apnea: a systematic review and meta-analysis

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a serious social health problem with significant implications on quality of life. Surgery for OSAHS has been criticized due to a lack of evidence to support its efficacy as well as the heterogeneous reporting of published outcomes. Moreover, the transoral robotic surgery (TORS) in the management of OSAHS is still in a relative infancy. Nevertheless, a review and meta-analysis of the published articles may be helpful. Among 195 articles, eight studies were included in the analysis. The mean of enrolled patients was 102.5 ± 107.9 (range 6-289) comprising a total of 820 cases. The mean age was 49 ± 3.27 and 285 patients underwent a previous sleep apnea surgery. The uvulopalatopharyngoplasty (UPPP) was the most common palatal procedure. The mean rate of failure was 34.4 % (29.5-46.2 %). Complications occurred in 21.3 % of the patients included in the analysis, most of them were classified as minor. Transient dysphagia represented the most common complication (7.2 %) followed by bleeding (4.2 %). TORS for the treatment of OSAHS appears to be a promising and safe procedure for selected patients seeking an alternative to continuous positive airway pressure (CPAP), although further researches are urgently needed.

Cutaneous metastasis from squamous carcinoma of the base of tongue

Context:

Cutaneous metastasis from head and neck cancer is uncommon and it is seen from laryngeal cancer. Cutaneous metastasis from the base of tongue is relatively rare.

Case Report:

A 55-year-old male, who was a treated case of squamous carcinoma of the base of tongue presented with metastatic nodule on the skin of face and thigh. But, there was complete resolution of the tumor at the primary site. In the present case, clinically obvious cutaneous nodules with metastasis appeared soon after the completion of treatment with concurrent chemo-radiotherapy. The metastasis to the skin of face clinically appeared like an inflammatory lesion. Fine needle aspiration cytology confirmed the diagnosis of metastasis to skin at both the sites.

Conclusion:

Our case has highlighted that there could be associated occult skin metastasis at the time of diagnosis in squamous carcinoma of the base of tongue.

A poor prognostic case of peripheral T-cell lymphoma in the base of tongue with chemotherapy followed by radiation therapy

A 59-year old male had odynophagia and globus sensation for 10 days prior to his visit. Endoscopically, a fungating mass was observed in the right side of the tongue base (BOT). The peripheral T-cell lymphoma (PTCL) was confirmed by a punch biopsy. The patient was classified as stage IIA according to the Ann Arbor staging classification. Radiation therapy (RT) using volumetric modulated arc therapy (VAMT) began after 8 cycles of CHOP chemotherapy. Although the patient achieved a complete remission without RT relating morbidity during the follow-up period, recurrence occurred in the right orbit at 3 months after treatment. The patient received RT with high energy electron on the right orbit. The salvage chemotherapy was followed by RT. The patient died of aggravation of PTCL at 17 months after VMAT. We report a poor prognostic case of PTCL in BOT with chemotherapy followed by RT.

Preoperative cephalometric analysis to predict transoral robotic surgery exposure

Transoral robotic surgery (TORS) is being increasingly used in the treatment of head and neck cancer and we wanted to determine the feasibility of predicting TORS access using cephalometric measurements obtained from preoperative imaging. 20 cephalometric measurements were obtained from imaging on 31 TORS base of tongue (BOT) resections and compared to adequacy of exposure. Three measurements were found to be significantly different between the restricted and adequate exposure groups. Distances from posterior pharyngeal wall (PPW) to hyoid, PPW to soft palate and epiglottis to vertical laryngeal angle were all statistically different between the two groups. Receiver operating characteristic (ROC) analysis revealed strong correlation to exposure for all three measurements with cut offs ≤30 mm between the PPW and the hyoid, ≤8.1 mm PPW and soft palate and ≥130° between the epiglottis and vertical plain of the larynx all representing restricted exposure. Duration of surgery for the restricted group, 85 min, was significantly longer than the adequate exposure group, 51 min (p = 0.026). Preoperative measurements of radiographic images of the oropharyngeal working space can predict restricted exposure for TORS resection of the BOT. These measures may be used in conjunction with other subjective assessment parameters to predict which patients could benefit from a staging endoscopy to determine adequate TORS exposure.

Comparative analysis of volumetric-modulated arc therapy and intensity-modulated radiotherapy for base of tongue cancer

The aim of this study was to compare the various dosimetric parameters of dynamic multileaf collimator (MLC) intensity modulated radiation therapy (IMRT) plans with volumetric modulated arc therapy (VMAT) plans for base of tongue cases. All plans were done in Monaco planning system for Elekta synergy linear accelerator with 80 MLC. IMRT plans were planned with nine stationary beams, and VMAT plans were done for 360° arc with single arc or dual arc. The dose to the planning target volumes (PTV) for 70, 63, and 56 Gy was compared. The dose to 95, 98, and 50% volume of PTV were analyzed. The homogeneity index (HI) and the conformity index (CI) of the PTV70 were also analyzed. IMRT and VMAT plan showed similar dose coverage, HI, and CI. Maximum dose and dose to 1-cc volume of spinal cord, planning risk volume (PRV) cord, and brain stem were compared. IMRT plan and VMAT plan showed similar results except for the 1 cc of PRV cord that received slightly higher dose in VMAT plan. Mean dose and dose to 50% volume of right and left parotid glands were analyzed. VMAT plan gave better sparing of parotid glands than IMRT. In normal tissue dose analyses VMAT was better than IMRT. The number of monitor units (MU) required for delivering the good quality of the plan and the time required to deliver the plan for IMRT and VMAT were compared. The number of MUs for VMAT was higher than that of IMRT plans. However, the delivery time was reduced by a factor of two for VMAT compared with IMRT. VMAT plans yielded good quality of the plan compared with IMRT, resulting in reduced treatment time and improved efficiency for base of tongue cases.

Survival patterns in patients with carcinoma base of tongue treated with external beam irradiation and salvage surgery

OBJECTIVE

The current study was designed to assess the treatment results and survival in the patients with carcinoma of base of tongue that were treated with primary radiotherapy, radiotherapy with chemotherapy and salvage surgery when indicated.

DESIGN

A prospective study was carried out in 78 cases of carcinoma of the base of tongue between 1995 and 1999.

METHODS

The majority of cases belonged to stage IV 60/78 (76.92%) as per AJCC staging. Radiotherapy in the dose of 60 Gy was given primarily to the patients with stage III tongue base cancer. Patients with early stage IV cancer were given split course radiotherapy followed by assessment for surgery. For the patients with advanced stage IV disease with poor general condition, palliative radiotherapy of 24 Gy with or without palliative chemotherapy was given. 15 patients were subjected to salvage surgery in the form of radical neck dissection alone (8 cases), extended total laryngectomy with neck dissection (3 cases), extended total laryngectomy (2 cases) and extended supraglottic laryngectomy with RND in 2 cases.

RESULTS

Two and 5 years Kaplan - Meier actuarial survival rates were 45% and 10% respectively with local control rates equivalent to survival rates. All surviving patients maintained good function and quality-of-life with few tolerable side effects.

CONCLUSIONS

External beam radiotherapy with salvage surgery results in satisfactory local and regional control in stage III and IV carcinoma base of tongue.