Squamous cell carcinoma metastatic to the lymph nodes of the parapharyngeal space: case series and systematic review.

Objective: Parapharyngeal space (PPS) is a rare and unusual site of head and neck squamous cell carcinoma (SCC) metastases. Treatment strategy for PPS metastases is still not well defined. This research aims to investigate the clinical implications and oncological outcomes of SCC metastases in PPS. Material and methods: A systematic review was conducted according to PRISMA criteria. The authors considered only articles reporting the history and treatment of patients with PPS SCC metastases. A retrospective chart review was conducted in two tertiary referral academic centers collecting data of patients with diagnosis of PPS SCC metastases between 2010 and 2023 to study their outcome based on clinical presentation and treatment strategy. Results: The retrospective chart review showed that the oropharynx was the most frequent primary tumour site. The advanced stage at the time of diagnosis was related to poorer survival and higher recurrence rates. A significant difference in 2-year overall survival in the subgroup of patients who experienced PPS metastases within the primary treatment and those who experienced PPS metastases as regional recurrence (66.7 vs 30.8%) was observed. Similar low survival rates were reported in the literature review with a mean overall and disease-free survival of 19.8 and 8.6 months, respectively. Conclusions: PPS metastases are associated with a dismal prognosis, especially when diagnosed as regional recurrence after primary treatment, due to patients' poor general conditions and difficulty of treatment.

Review of retropharyngeal and parapharyngeal nodal metastasis of papillary thyroid carcinoma.

BACKGROUND: Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. In rare instances, PTC has metastasized to the retropharyngeal and parapharyngeal nodes. This is hypothesized to occur due to an aberrant lymphatic channel or via retrograde lymphatic flow following previous neck dissection. METHODS: A literature search was conducted with keywords "parapharyngeal," "retropharyngeal," and "papillary thyroid carcinoma." RESULTS: 46 articles were identified for a total of 135 cases. The most common presenting symptom was lymphadenopathy followed by pharyngeal mass and dyspnea. 38.03 % of patients were asymptomatic. Of cases including initial treatment history, 94.44 % had a history of neck dissection. The transcervical approach was the most utilized to resect the tumors, although in recent years trans-oral robotic surgery (TORS) has also been used. CONCLUSION: PTC metastatic to the retropharyngeal and parapharyngeal nodes is a rare occurrence that can be difficult to diagnose due its indolent nature.

Management of Parapharyngeal Metastatic Medullary Thyroid Carcinoma Via a Combined Trans-Cervical and Trans-Oral Robotic Approach.

INTRODUCTION: Medullary thyroid carcinoma constitutes 5% to 10% of all thyroid cancers. Metastatic adenopathies may pose challenges in intricate anatomical locations, such as the parapharyngeal space. A rare case of metastatic medullary thyroid carcinoma in the parapharyngeal space has been treated in our unit using combined trans-cervical trans-oral robotic surgery. Our objective was to provide a detailed description of the surgery performed on this patient. METHOD: We reported a singular case report worth of interest. RESULT: A 42-year-old woman was addressed in our unit for the management of a medullary thyroid carcinoma adenopathy located in the right parapharyngeal space. A parapharyngeal 40.0 mm × 25.0 mm × 12.0 mm adenopathy was removed using a combined trans-cervical and trans-oral robotic approach without sacrifice or injury of vascular or nervous structure. Neither the tracheostomy nor the feeding tube was implemented. Feeding was resumed on postoperative day 1 and hospitalization spanned 7 days. CONCLUSION: An innovative combined trans-cervical and trans-oral robotic surgery approach was conducted to address a metastatic medullary thyroid carcinoma in the parapharyngeal space. This surgical technique allowed us to circumvent the need for a trans-mandibular approach, tracheostomy, and feeding tube and enabling successful tumor removal without fragmentation. Postoperative care was significantly eased. The sole complication observed was dysphonia, likely resulting from intra-operative stretching of the vagus nerve during the dissection of the carotid artery.

[An anatomical road map of the parapharyngeal internal carotid artery in lateral and endoscopic ventral approaches].

Objective:To describe the road map of the lateral and endoscopic ventral approaches for the pharyngeal segment of the internal carotid artery, propose a sub-segmentation scheme, systematically and comprehensively understand its anatomical details and relationships with the surrounding structures. Methods:Five fresh cadaveric head specimens（10 sides in total） were dissected through lateral and endoscopic ventral approaches to evaluate the anatomical details of the parapharyngeal internal carotid artery and its relationship with the surrounding structures. Results:From the bifurcation of the common carotid artery to the vertical part of the internal carotid artery, alongside the direction of blood flow, the parapharyngeal internal carotid artery passes through four distinct anatomical tissues. Based on this, the parapharyngeal internal carotid artery can be divided into four sub-segments: nerve, muscle, fascia and osseous sub-segments. The boundaries and important adjacent structures of each segment are described in detail. Conclusion:The anatomical road map of the parapharyngeal internal carotid artery and the sub-segmentation scheme serving as a practical guide to navigate modular endoscopic skull base surgery of the parapharyngeal space while reduce the risk of internal carotid artery injury.

[Research progress in the anatomy and surgical approach of the parapharyngeal space].

The parapharyngeal space, a complex fascial compartment within the head and neck region, encompasses crucial anatomical structures including blood vessels and nerves. Tumors occurring within this space are rare, with the majority being benign in nature. Surgical intervention remains the primary treatment modality; however, managing parapharyngeal space tumors poses significant challenges due to their intricate anatomical configuration. Conventional open surgical approaches have been associated with significant tissue damage and a high prevalence of postoperative complications. Recently, advancements in anatomical studies and surgical techniques have led to significant progress in understanding parapharyngeal space anatomy and improving surgical management. This article aims to provide a comprehensive overview of these developments.

[Efficacy analysis of 23 cases of parapharyngeal space tumors removed by oral approach assisted by plasma and high-definition endoscopic system].

Objective:To explore the selection, efficacy and application of indications for parapharyngeal space tumor resection assisted by plasma and HD endoscopic system through oral approach. Methods:The clinical data of 23 patients with parapharyngeal space tumor resection assisted by plasma and HD endoscopic system were retrospectively analyzed in Department of Otolaryngology Head and Neck Surgery, the First Affiliated Hospital of Bengbu Medical University from January 2013 to June 2023. All cases were examined by high-resolution CT and MRI before operation, and some cases were examined by CTA or DSA. During the operation, the high definition nasal endoscopic recording system was assisted, and low temperature plasma knife was used in some cases. The follow-up time was from 3 to 115 months, and the median follow-up time was 45 months. Results:There were no deaths in this group. All patients had complete tumor resection. The maximum tumor diameter was as follows: （5.20±1.00） cm, the operation time was（128.70±46.67） min, and the average blood loss was（80.87±32.74） mL. One case of vascular smooth muscle tumor had more bleeding during the operation and was assisted by tracheotomy after operation. One case of nourishing vascular bleeding after operation of giant Schwannoma was investigated and hemostasis + external carotid artery ligation. Bleeding in the remaining cases was below 120 mL. Postoperative pathologies were all benign tumors, including 11 pleomorphic adenoma, 4 schwannoma, 2 base cell adenoma, 1 epidermoid cyst, 1 lymphatic cyst with infection, 1 angiomyoma, 1 solitary fibroma, 1 salivary gland cyst, and 1 tendon giant cell tumor. All patients were followed up. One patient originating from vagal schwannoma had 2-month vocal cord paralysis and 1 recurrence（recurrence of the skull base of schwannoma）. Conclusion:Oral approach assisted by plasma and high-definition endoscopic system is suitable for partial selective resection of benign tumors in parapharyngeal space, which has the advantages of less trauma and rapid recovery. When the tumor is blood-rich, suspected to be malignant, the top of the tumor is deep into the cranial base nerve canal,located outside the internal carotid artery, and larger than 6.0 cm considering pleomorphic adenoma, it is recommended to conduct an external open or auxiliary cervical small incision approach.

Solitary fibrous tumor of the parapharyngeal space: report of 2 cases and a literature review.

The solitary fibrous tumor (SFT) is usually described as a lesion arising from the pleura. Rarely, it has been described in the parapharyngeal space (PS). This study aims to report two cases of SFT in the PS and to perform a literature review on this topic. Two patients undergoing surgical resection of a SFT in the PS, were reported. A literature review on SFT of the PS, was also performed. Two patients were analyzed. Both patients underwent surgical resection, followed by adjuvant radiotherapy, for SFT arising from the PS. The postoperative course was uneventful and both patients recovered well after the procedure. No recurrences were diagnosed during the followup. SFT of the PS is an infrequent entity. Surgical resection is the most used treatment, and adjuvant radiation should be considered in patients with recurrence risk factors or distant metastases.

Parapharyngeal and retropharyngeal infections in children: Kawasaki disease needs vigilance.

OBJECTIVE: Kawasaki Disease (KD) may mimic Parapharyngeal (PPI) and Retropharyngeal Infections (RPI), leading to misdiagnosis as Deep Neck Infections (DNIs). The treatment plans for the two diseases are different, and delayed treatment can lead to serious complications. Therefore, prompt diagnosis and management are necessary. This study was performed to evaluate the clinical features of KD mimicking DNIs and explore the treatment options. METHODS: Children with cellulitis or abscess in parapharyngeal or retropharyngeal space in neck CT were included in this study. The medical records of enrolled children were retrospectively reviewed. RESULTS: In total, 56 children were diagnosed with PPI or/and RPI. Twenty-two (39.3%) participants were eventually diagnosed with KD, and 34 (60.7%) were diagnosed with DNIs. Compared with the DNIs group, the KD group had a higher body temperature (p=0.007), and higher levels of AST (p=0.040), ALT (p=0.027), and ESR (p=0.030). Deep cervical cellulitis (p=0.005) were more common in the KD group. However, deep neck abscess often occurred in the DNIs group (p=0.002), with parapharyngeal abscess being the most common type of abscess (p=0.004). The KD mimicking DNIs cases did not respond to antibiotic treatment, but symptoms significantly improved after the use of Immunoglobulin (IVIG) and aspirin. CONCLUSION: Children with KD may exhibit retropharyngeal or parapharyngeal inflammation in the early stages. KD should be considered a differential diagnosis for children with DNIs, high fever, and no response to antibiotic therapy. Surgery in KD mimicking deep neck abscess requires caution. LEVEL OF EVIDENCE: I.

Cervical approach for prestyloid parapharyngeal pleomorphic adenoma resection.

OBJECTIVE: To describe the key points of cervical resection for prestyloid parapharyngeal pleomorphic adenoma and to discuss the role of modern imaging. OBSERVATION: Retrospective case series of 10 patients (4 women and 6 men, age 29-63 years) with prestyloid parapharyngeal pleomorphic adenoma with 2 to 8cm largest diameter on MRI, consecutively resected via a cervical approach between 2000 and 2020 in a French tertiary university referral care center. Seven patients had a minimum 10 years' follow-up, and one was lost to follow-up before the fifth postoperative year. Peri- and postoperative complications comprised great auricular nerve transection without subsequent symptomatic neuroma (2 patients), associated transoral approach to free the upper pole of the adenoma (2 patients), capsule effraction (3 patients), and hematoma (1 patient). There were no cases of facial paresis or palsy, other cranial nerve impairment, trismus, auriculotemporal or first-bite syndrome. One of the three patients with capsule effraction showed local recurrence at month 17. CONCLUSION: In agreement with previous reports, the present case series confirmed the role of the cervical approach to resect prestyloid parapharyngeal pleomorphic adenoma, and hence the need to continue teaching it.

[Analysis of surgical approaches and mandibular treatment strategies for different types of tumors involving parapharyngeal space].

In view of the surgical complexity of parapharyngeal space tumors involved, this paper summarized the disease data of patients with parapharyngeal space tumors involved in the Department of Oral and Maxillofacial Surgery, the First Hospital of Shanxi Medical University from January 2015 to January 2021. It also summarized the surgical approach and mandibular management, so as to explore surgical strategies for different characteristics of parapharyngeal space tumors involved. A total of 49 patients, including 28 males and 21 females, median age 52 years (range 24-72 years). They were treated with four surgical approaches for tumor resection, 25 cervical approach, 5 cheek and neck approach, 3 transoral approach, and 16 cervical-maxillary approach. Among the patients treated with cervical-maxillary approach, 3 patients were treated with mandible square resection, and 6 patients were treated with temporary mandible dissection. Seven cases were treated with tumor resection and partial mandibular resection. There are various surgical approaches and mandibular management methods involving tumors in the parapharyngeal space, and clinical decisions should be made based on tumor diameter, location, boundary, blood supply and pathological types.

The transcervical-transparotid corridor for management of parapharyngeal space neoplasms: strengths and limits in a bi-institutional retrospective series.

BACKGROUND AND PURPOSE: Parapharyngeal space (PPS) neoplasms represent 1% of all head and neck tumors and are mostly benign. Surgery is the mainstay of treatment and the transcervical-transparotid (TC-TP) corridor still represents the workhorse for adequate PPS exposure. Our series investigates strengths and limits of this approach on a multi-institutional basis. METHODS: We reviewed consecutive patients submitted to PPS surgery via TC-TP route between 2010 and 2020. Hospital stay, early and long-term complications, and disease status were assessed. RESULTS: One hundred and twenty nine patients were enrolled. Most tumors were benign (79.8%) and involved the prestyloid space (83.7%); the median largest diameter was 4.0 cm. The TC-TP corridor was used in 70.5% of patients, while a pure TC route in about a quarter of cases. Early postoperative VII CN palsy was evident in 32.3% of patients, while X CN deficit in 9.4%. The long-term morbidity rate was 34.1%, with persistent CN impairment detectable in 26.4% of patients: carotid space location, lesion diameter and malignant histology were the main independent predictors of morbidity. A recurrence occurred in 12 patients (9.4%). CONCLUSIONS: The TC-TP corridor represents the benchmark for surgical management of most of PPS neoplasms, though substantial morbidity can still be expected.

Endoscopic endonasal combined transoral medial approach to the nasopharynx, parapharyngeal space, and jugular foramen.

OBJECTIVE: This study aimed to validate the feasibility of an endoscopic endonasal combined transoral medial approach for treating lesions in the nasopharynx, parapharyngeal space (PPS), and jugular foramen. METHODS: Anatomical and imaging information of six patients who underwent surgery via this approach were reviewed and analyzed. RESULTS: The feasibility and advantages of the endoscopic endonasal combined transoral medial approach, which uses an inside-to-outside medial surgical corridor, were identified. Total resection was achieved in 3 cases with benign tumors. Safe resection margins were obtained in 2 cases with recurrent nasopharyngeal carcinoma (NPC). Pathological biopsy of NPC lesion between the Eustachian tube and arterial sheath was achieved. The internal carotid artery (ICA) was accurately located and protected in all cases and no complications occurred. CONCLUSION: Lesions in the nasopharynx, PPS, and jugular foramen can be directly assessed via this approach. The ICA can be well identified during the surgery.

Parapharyngeal space ectopic thyroid with eutopic papillary thyroid cancer: A case report.

BACKGROUND: Ectopic thyroid is a rare condition. Here we report an extremely rare case of parapharyngeal space ectopic thyroid, which has simultaneously found the papillary thyroid carcinoma of the eutopic thyroid. CASE PRESENTATION: A 54-year-old woman was admitted to our hospital for a thyroid tumor and neck lymph nodes. CT and MR imaging revealed the presence of a thyroid right node, as well as a right parapharyngeal mass with a diameter of 2.5 × 2.3 cm. PET-CT was also performed to diagnose further, revealing that the suv metric of the PPS mass was 4.03. Considering that the mass was asymptomatic, we did not handle it at the first thyroid surgery. However, when the patient underwent a radioactive iodine scan before the radioactive iodine treatment, the imaging showed that the mass could intake the iodine. So, we arranged the second surgery for this mass, and the postoperative pathological examination confirmed the mass was well-differentiated thyroid tissue. CONCLUSION: Parapharyngeal ectopic thyroid with eutopic thyroid cancer is extremely rare. Preoperative imaging examination can significantly avoid the missed diagnosis of this disease. Surgical resection is recommended for the ectopic thyroid while the eutopic thyroid is found to be malignant.

Differentiation between pleomorphic adenoma and schwannoma in the parapharyngeal space: histogram analysis of apparent diffusion coefficient.

OBJECTIVES: To elucidate the differences between pleomorphic adenomas and schwannomas occurring in the parapharyngeal space by histogram analyses of apparent diffusion coefficient (ADC) values measured with diffusion-weighted MRI. METHODS: This retrospective study included 29 patients with pleomorphic adenoma and 22 patients with schwannoma arising in the parapharyngeal space or extending into the parapharyngeal space from the parotid region. Using pre-operative MR images, ADC values of tumor lesions showing the maximum diameter were measured. The regions of interest for ADC measurement were placed by contouring the tumor margin, and the histogram metrics of ADC values were compared between pleomorphic adenomas and schwannomas regarding the mean, skewness, and kurtosis by Wilcoxon's rank sum test. Subsequent to the primary analysis which included all lesions, we performed two subgroup analyses regarding b-values and magnetic field strength used for MRI. RESULTS: The mean ADC values did not show significant differences between pleomorphic adenomas and schwannomas for the primary and subgroup analyses. Schwannomas showed higher skewness (p = 0.0001) and lower kurtosis (p = 0.003) of ADC histograms compared with pleomorphic adenomas in the primary analysis. Skewness was significantly higher in schwannomas in all the subgroup analyses. Kurtosis was consistently lower in schwannomas but did not reach statistical significance in one subgroup analysis. CONCLUSIONS: Skewness and kurtosis showed significant differences between pleomorphic adenomas and schwannomas occupying the parapharyngeal space, but the mean ADC values did not. Our results suggest that the skewness and kurtosis of ADC histograms may be useful in differentiating these two parapharyngeal tumors.

Head and neck lipoblastoma in children: A case report and systematic review.

BACKGROUND: Lipoblastoma is a rare and benign tumor arising from embryonal fat cells. It develops primarily in infancy and early childhood. We present a case study of a 10-month-old child treated for an extensive tumor of the infratemporal fossa and parapharyngeal space. The systematic review of 60 reports in 80 children with lipoblastoma of the head and neck is also reported. MATERIAL AND METHODS: Systematic review of all articles included lipoblastomas of the head and neck area in children published from 1964 to 2022 in the PubMed database was conducted. Clinical presentation of extensive lipoblastoma of the head and neck in a child. RESULTS: On the basis of all inclusion criteria 83 articles were identified concerning pediatric lipoblastoma. There were 36 F (45%) and 39 M (48%), in 6 patients, (7%) gender was not specified. Ages ranged from 0mth (6h) to 15 yo (180mth). The tumor was located in the head in 22 (27%) cases, while the neck area accounted for 53 (65%) cases. General description without precise location was shown in 6 (7%) cases. All patients underwent complete surgical excision. Post surgical recurrence was noted in 6% clinical cases in the analyzed articles. CONCLUSIONS: Lipoblastoma is characterized by a rapidly growing predominantly adipose mass. The treatment of choice is complete surgical excision. In selected cases when the pathology is hard to reach, as a consequence of the extensive penetration of the mass, we recommend performing the procedure with an interdisciplinary team. Endoscopy assistance and microdebrider significantly facilitated the removal of pathology in the described advanced case of lipoblastoma. This is the only case reported in the pediatric literature of a head and neck lipoblastoma, where due to extensive involvement and location of the disease the cranial nerves V2 and inferior alveolar branch of V3 could not be spared. Long-term follow-up even to 10 years is required because there is a reported tendency for these tumors to recur.

Differentiation of neurogenic tumours and pleomorphic adenomas in the parapharyngeal space based on texture analysis of T2WI.

BACKGROUND: The purpose of this study was to identify neurogenic tumours and pleomorphic adenomas of the parapharyngeal space based on the texture characteristics of MRI-T2WI. METHODS: MR findings and pathological reports of 25 patients with benign tumours in the parapharyngeal space were reviewed retrospectively (13 cases with pleomorphic adenomas and 12 cases with neurogenic tumours). Using PyRadiomics, the texture of the region of interest in T2WI sketched by radiologists was analysed. By using independent sample t-tests and Mann‒Whitney U tests, the selected texture features of 36 Gray Level Co-Occurrence Matrix (GLCM) and Gray Level Dependence Matrix (GLDM) were tested. A set of parameters of texture features showed statistically significant differences between the two groups, which were selected, and the diagnostic efficiency was evaluated via the operating characteristic curve of the subjects. RESULTS: The differences in the three parameters - small dependence low level emphasis (SDLGLE), low level emphasis (LGLE) and difference variance (DV) of characteristics - between the two groups were statistically significant (P < 0.05). No significant difference was found in the other indices. ROC curves were drawn for the three parameters, with AUCs of 0.833, 0.795, and 0.744, respectively. CONCLUSIONS: There is a difference in the texture characteristic parameters based on magnetic resonance T2WI images between neurogenic tumours and pleomorphic adenomas in the parapharyngeal space. For the differential diagnosis of these two kinds of tumours, texture analysis of significant importance is an objective and quantitative analytical tool.

[Schwannoma of the parapharyngeal space]. / Shvannoma parafaringeal'nogo prostranstva.

Schwannoma is a benign neoplasm that develops from the Schwann cells of the nerve sheath. The share of neurogenic tumors of the parapharyngeal space accounts for 0.5% of all neoplasms of this localization. The article demonstrates a case from practice, presents the clinical features, diagnostics and methods of treatment for patients with pharyngeal neuromas. The peculiarity of the presented clinical observation is due to the rare occurrence of this pathology and the large size of the schwannoma in the long-term asymptomatic course of the disease.

Perioperative stroke in parapharyngeal space schwannoma: an unusual, dreaded complication.

BACKGROUND: Post-styloid parapharyngeal space tumours (PPS) have a notorious course owing to their anatomy and proximity to neurovascular bundles. Nerve injuries are usual outcomes in schwannomas. Our case is the first documented complication of contralateral hemiplegia occurring in the postoperative period in a benign PPS tumour. CASE REPORT: A 24-year-old presented with a swelling on the left lateral aspect of the neck, diagnosed as a PPS schwannoma. He underwent transcervical excision with mandibulotomy with extracapsular dissection of the tumour. Contralateral hemiplegia, as a dreaded complication, was encountered. He was managed conservatively according to ASPECTS stroke guidelines by the critical care team. On a regular follow-up, he noticed an improvement in the lower limb with subsequent upper limb power. CONCLUSION: Perioperative stroke is a dreaded complication involving PPS in large benign tumours. To prevent unforeseen circumstances, necessary preoperative patient counselling and immense intraoperative care should be taken while dissecting the major vessels.