Diagnosis and treatment of Schwannoma of the parapharyngeal space on the example of a 14-year-old male patient

Objective To investigate the operative methods for benign tumors in parapharyngeal space. Methods The clinical data from 48 patients with benign tumors in parapharyngeal space admitted to Otolaryngology Hospital, the First Affiliated Hospital of Zhengzhou University from February 2013 to February 2018 were retrospectively analyzed. All patients underwent imaging examination before surgery. Thirty-two cases of parapharyngeal space tumors were resected by trans-cervical approach and 16 cases by trans-oral approach. The therapeutic effects of the two methods were compared. Results Pathological results showed 20 cases (41.7%) of schwannoma, 17 cases (35.4%) of pleomorphic adenoma, 4 cases (8.3%) of neurofibroma, 4 cases (8.3%) of hemangioma and 3 cases (6.3%) of cyst. During hospitalization, 6 cases who were given trans-cervical approach surgery had complications, and 2 cases treated by trans-oral approach surgery had complications. Postoperative follow-up ranged from 10 to 62 months. Two cases treated by trans-oral approach recurred, and 3 cases treated by trans-cervical approach recurred. All of the 5 patients were cured by performing operation again. Statistical analysis showed that there was no significant difference in gender, age, length of hospital stay, incidence of complications during hospitalization or recurrence between the two surgery approaches (P>0.05); however, there was a significant difference in operation duration and intraoperative bleeding between the two approaches (P<0.05). Conclusions The trans-oral approach is a better surgical method for tumors located in the anterior half of parapharyngeal space, while trans-cervical approach is recommended to neurogenic tumors located in the posterior half of parapharyngeal space. Key words: Parapharyngeal space neoplasms; Trans-cervical approach; Trans-oral approach

Lesions in the parapharyngeal space (PPS) are diverse. Management strategies for commonly seen PPS lesions (i.e., pleomorphic adenoma and schwannoma) have been widely accepted while less well defined for more rare PPS tumors. The purpose of this study was to retrospectively review rare entities of the PPS, and to evaluate the role of minimally invasive surgical approaches for management of rare entities in this complex region. From Jan 1, 2010 to Dec 31, 2021, 328 patients who harbored PPS tumors were included and retrospectively reviewed. Those patients with a common PPS tumor (pleomorphic adenoma and schwannoma) were excluded. Fifty-one patients with rare PPS entities were included (42 patients with benign lesions and 9 patients with malignancies). Demographics, pathological outcomes, and treatment strategies for patients with rare entities were evaluated and retrospectively reviewed. A minimally invasive surgical approach (i.e., transoral endoscopic approach, or as a combined approach) was adopted in 52.4% of cases for extirpation of benign cases in the PPS. For malignancies in the PPS, the transoral endoscopic approach was applied in 66.7% of malignant cases such as metastatic lymph node dissection or biopsy. Moreover, the traditional approach (i.e., transcervical transparotid approach with or without mandibulotomy) accounted for 47.6% and 33.3% for management of complex benign and malignancies in the PPS, respectively. Rare entities arising in the PPS are diverse. An endoscopic transoral approach can be appropriately utilized in more than half of rare entities including both the benign tumors and malignancies in the PPS.

Parapharyngeal space tumours are rare, mostly benign and present few symptoms, being difficult to diagnose it early. CT scan and MR are necessary for topographical diagnosis. Surgical resection is the best possible treatment option, but the approach remains a challenge, as there are several vital elements contained in the parapharyngeal space and, thus, adequate visualization is needed. Different surgical approaches have been described: transcervical-submandibular, transparotid, transmandibular, transoral and combined approaches. Transoral approach is the most controversial one due to cited limited exposure, which can lead to neurovascular injury or incomplete removal of the lesion. It is seldom performed and only for small, extra-parotid and non-vascular tumours of the parapharyngeal space. Wide access to endoscopic equipment in our institute allowed us to perform medium to large benign parapharyngeal tumour resection usig the transoral approach. The use of endoscopic assistance for transoral approach provided direct and magnified visualization of the parapharyngeal space, reducing tissue damage, ensuring adequate hemostasis (which lead to less amount of bleeding) and also confirming complete resection prior to closure. In addition, compared to transcervical approach, transoral approach shortened hospitalization time and improved cosmetic appearance. Benign parapharyngeal space tumours not involving critical structures from the parapharyngeal space can be completely resected by an endoscopic-assisted transoral approach with good functional and cosmetic outcome.

The advent of transoral robotic surgery (TORS) has allowed transoral approaches for parapharyngeal space (PPS) tumours to be re-evaluated. It provides enhanced visualisation and instrument access for appropriate tumours. We describe a specific technique, TORS narrow-field oropharyngectomy, that is ideal for benign PPS tumours which have been violated by intra-oral biopsy or incision and drainage. This allows the contaminated, overlying oropharyngeal mucosa to be resected en-bloc with the PPS tumour, reducing the risk of local recurrence. This technique provides a window into the PPS, improving visualisation of underlying neurovascular structures as well as the tumour. This reduces the risk of tumour spillage and leads to superior vascular access and haemorrhage control. This technique is only applicable to PPS tumours that are appropriate for transoral approaches and is specifically designed for those selected patients that have been placed at risk of seeding or local scarring by intra-oral procedures prior to definitive resection. We present two such cases: a 38-year-old male with a PPS inflammatory cyst and a 66-year-old female with a PSS pre-styloid Schwannoma.

Introduction Para pharyngeal space (PPS) tumours are mostly benign (80%). These are rare tumours of head and neck with incidence of about 0.5% [1]. Schwannomas are the most common neurogenic tumours of head and neck, second most common PPS tumours. One such classical presentation of schwannoma video presentation is given here. Case Blog The usual presentation of PPS tumours are with neck swelling. This patient had a classical symptom of swelling increasing in size with valsalva. The reason for this could be, most neurofibromas arise from Schwann cells and are usually subcutaneous, hence increasing in size with valsalva. One thing we have to be aware about these tumours is, they may be multiple, and may be associated with Von Recklinghausen’s disease (see Video). The patient was having nasal intonation of speech that can be appreciated. Also on valsalva we can see the mass is increasing in size. FNAC reports turned out to be schwannoma. MRI scan was done. Tran’s cervical approach was planned. Anticipating difficult intubation pre-operative tracheostomy was done. HPE reports turned out to be schwannoma. Discussion FNAC, radiology studies are mandatory for the evaluation of PPS tumours. FNAC can be USG or CT guided for a better result. CT and MRI are very essential for the pre-op planning, especially for the approach to be planned in a better way. Schwannomas have the characteristic picture of antoni A and antoni B bodies [2]. There was no pleomorphism or increased nuclear cytoplasmic ratio. The various other tumours of the PPS are pleomorphic adenoma, paraganglioma, malignancy of salivary gland, metastasis from adjacent regions. Conclusion Parapharyngeal space tumours have complex anatomical distribution with subtle presentation. Preoperative radiological assessment is very essential for the head and neck surgeon to know the pattern of spread and to remove the tumour completely

The transoral robotic approach to parapharyngeal space (PPS) tumors is a new technique with limited data available on its feasibility, safety, and efficacy. We analyzed our experience with transoral robotic excisions of PPS tumors to evaluate the safety and efficacy of this technique. Retrospective chart analysis at tertiary academic medical center. From July 2010 to June 2014, 17 patients who had transoral robotic excision of PPS tumors were included in the study. Our cohort had an average age of 61.6 years and was 52.9% male. All patients had successful removal of their PPS tumors, and the average size of the tumors was 27.3 cm(3) (range 2-80 cm(3) ). Two cases (11.7%) required a cervical incision to assist with tumor removal. The average total operative time was 140.5 minutes. Two PPS PAs had focal areas of capsule rupture and one was fragmented. The average length of stay was 1.8 days (range 1-7 days), and all patients were discharged on an oral diet. Three patients experienced complications. There was no clinical or radiographic evidence of recurrence. This is the largest single-institution case series of transoral robotic approaches to PPS tumors. We demonstrate that this approach is feasible and safe but also note limitations of the robotic approaches for tumors on the far lateral and superior areas of the PPS, which required transcervical assistance. There were no patients who demonstrated recurrent tumor either radiographically or clinically. 4. Laryngoscope, 126:1776-1782, 2016.

BackgroundTumors of the parapharyngeal space (PPS) are rare, accounting for 0.5–1.5% of all head and neck tumors. The anatomy of the PPS is responsible for a wide variety of tumors arising from the PPS. This series of 99 PPS tumors provides an overview of the clinical course and management of PPS tumors.Materials and methodsThis retrospective study included clinical data from patients treated for PPS tumors from 1991 to 2012 (warranting at least a 4-year follow-up) at the VU University Medical Center, Amsterdam, The Netherlands.ResultsFifty percent were salivary gland tumors, 41% were neurogenic and 9% had a different origin. 18.2% of the PPS tumors were malignant. The most reported symptom at presentation was swelling of the neck and throat. In 14%, the PPS tumor was an accidental finding following imaging for other diagnostic reasons. Cytology showed an accuracy rate of 73.1% (19/26). The positive predictive value of a malignant cytology result was 86% (95% CI 42.1–99.6%). Surgery was performed in 55 patients (56%). The most frequently performed approach (56%) was the cervical–transparotid approach, followed by the cervical (25%), transmandibular (16%) and transoral (2%) approach. Nine patients died of the disease, of which seven patients had a malignant salivary gland tumor, one patient had a pleomorphic adenoma at first diagnosis which degenerated into carcinoma ex pleomorphic adenoma and one patient died of metastatic renal cell carcinoma.ConclusionThis large single-centre report on PPS tumors shows that careful diagnostic work up and proper surgical planning are important in this specific and rare group of head and neck tumors. Surgery was the main treatment (56%) for parapharyngeal tumors. Management of parapharyngeal neurogenic neoplasms generally consists of active surveillance due to peri-operative risk for permanent cranial nerve damage. The histopathological diagnoses were consistent with previous reports.

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Objective To observe and compare the effects and complications of endoscope-assisted transoral approach and lateral cervical approach in the resection of parapharyngeal space (PSS) tumors. Methods From January 2013 to September 2021, 69 patients with parapharyngeal space tumors in the Affiliated Hospital of Jiangnan University were divided into the control group (n = 37) and the observation group (n = 32) according to the mode of operation. The tumors in the parapharyngeal space were resected by the lateral cervical approach in the control group, and the tumors in the parapharyngeal space were removed by endoscopy-assisted transoral approach in the observation group. The general clinical data and operation conditions of the two groups, including operative blood loss, operation time, drainage volume and drainage time, hospital stay, perioperative pain degree, and tumor resection rate were collected and analyzed statistically. The patients were followed up for 6 months, and the complications of the two groups were recorded. Results Compared with the control group, the operation time in the observation group was significantly shorter, and the amount of intraoperative bleeding in the observation group was significantly less than that in the control group, and the difference was statistically significant (P < 0.05). The postoperative drainage was less and the hospital stay in the observation group was shorter than that in the control group, and the difference was statistically significant (P < 0.05). There was no significant difference in tumor resection rate between the two groups. The visual analog scale (VAS) score on the 1st and 3rd day after operation in the observation group was lower than that in the control group. After treatment, some patients in the two groups had complications such as nerve injury, dysphagia, difficulty in mouth opening, massive hemorrhage, and parotid fistula. The total incidence of complications in the observation group was lower than that in the control group, and the difference was statistically significant (P < 0.05). Conclusions The effect of the endoscope-assisted transoral approach is similar to that of the lateral cervical approach in the resection of tumors in parapharyngeal space, but the endoscope-assisted transoral approach has shorter operation time, less intraoperative bleeding, and less postoperative drainage. The indwelling time and hospital stay of the drainage device were shorter than those of the patients with transcervical approach, and the perioperative stress response of patients with endoscope-assisted transoral approach is mild, which is beneficial to the physical and mental recovery of the patients.

Benefits and drawbacks of robotic surgical approaches for parapharyngeal space (PPS) tumors remain undetermined. The purpose of this study is to compare surgical outcomes of PPS tumor patients who underwent robotic surgery with those of patients who received conventional surgical treatment. We retrospectively analyzed clinicopathologic data from 136 patients who underwent surgical removal of PPS tumors via conventional or robotic approaches. We identified PPS tumors in pre- and poststyloid regions in 87 (64%) and 49 (36%) patients, respectively. There were 48 (35.3%) pleomorphic adenomas, 36 (26.5%) schwannomas, and 24 (17.6%) paragangliomas. Conventional surgical techniques were performed in 83 patients, and robotic surgical approaches were administered to 53 patients. Transcervical-parotid and transcervical approaches were most commonly performed in conventional surgery, while transoral and retroauricular approaches were the preferred surgical methods in robotic surgery for pre- and poststyloid PPS tumors, respectively. Robotic surgery resulted in less estimated blood loss during poststyloid PPS tumor surgery. Postoperative cranial nerve complications were noted in 36 of 83 cases (43.4%) in the conventional surgery group and in 17 of 53 cases (32.1%) in the robotic surgery group. Intraoperative tumor spillage of pleomorphic adenoma showed no significant differences between the two groups (13.6% in conventional vs. 15.4% in robotic surgery). The mean follow-up time was 4.9 ± 3.4years, and recurrences were observed in two patients during follow-up without a significant difference between the two groups (4.5% in conventional vs. 3.8% in robotic surgery). Robotic surgery in PPS tumors is feasible through transoral, retroauricular, or combined approaches and provides treatment outcomes comparable to those of conventional open surgery.

Parapharyngeal space (PPS) is the anatomical area lateral to the upper pharynx and clinically important due to PPS tumors. They account for less than 1% of head and neck neoplasms. Both benign and malignant neoplasms may arise there and typical for this localization is diversity of histological origin. Complete surgical excision is still the basis of treatment. Evaluation of the results of surgical treatment of PPS tumors in the Department of Otolaryngology at the Medical University over the period 2015-2017. A retrospective analysis of medical records including complaints, physical examination, results of imaging studies, surgical approach, postoperative complication and histopathological results in 22 patients with a diagnosis of a PPS tumors. The most frequent complaints reported by the patients were: discomfort in the throat, dysphagia, hearing disorders and a palpable tumor on the neck. Asymptomatic course of the disease was demonstrated in 4 cases. All patients were treated surgically: 2 with transoral approach, 9 with transparotid-transcervical approach, 11 with transcervical approach. In most cases the tumor was removed radically. In 2 patients intracapsular tumor resection was performed. Based on histopathological examination the benign lesions dominated (18/22). In 4 cases malignant neoplasms were diagnosed: carcinoma ex pleomorphic adenoma, adenoid cystic carcinoma and two cases of squamous cell carcinoma. The most common origin of PPS tumors was deep lobe of parotid gland and for this group 11 patients had diagnosis of pleomorphic adenoma. Other diagnosis included: paraganglioma, neurofibroma, hemangioma, lymphangioma and rhabdomyoma. Postoperative complications occurred in 9 patients and presented as hoarseness and dysphagia due to paresis of the lower group of cranial nerves (IX, X, XII). Significant intraoperative bleeding during surgery occurred in 2 cases and ligation of the external carotid artery was necessary. Due to the anatomical topography of PPS and its content with the essential vessels and the lower group of cranial nerves, the surgical treatment of pathology of this area is still a challenge for head and neck surgeons. The decrease of voice quality and impaired speech and swallowing should always be considered as complications post the surgical resection in PPS.

Extracapsular dissection (ECD) is thought to be effective in treating benign tumors and minimally invasive. Nonetheless, its application and feasibility in treating benign parapharyngeal space (PPS) tumor, the neoplasm located in the complex anatomical space, have never been investigated. The aim of this study is to evaluate the utility and efficacy of transcervical ECD in treating benign PPS tumors. From 1996 to 2009, 54 patients with PPS tumors were treated by the designated surgeon. Excluding nine patients who were initially regarded as the potential candidates for ECD treatment but failed to meet the inclusion criteria, 22 patients who received the procedure were retrospectively analyzed. In 22 enrolled patients, 10 had pleomorphic adenoma while 6 had neurilemmoma. There were 13 PPS tumors located in the prestyloid space and 9 in the poststyloid space. The median volume of PPS tumors was 22.6 cm(3), and the median distance from tumor to skull base was 2.3 cm. The median length of incision was 4.5 cm with the ECD intervention. No major intra- or post-operative complications were noted and post-operative courses were unremarkable in long-term follow-up. This study demonstrates that ECD is an effective and safe treatment for selected benign PPS tumors. It has a favorable clinical outcome and an acceptable aesthetic result, and can be performed in a minimally invasive fashion. Therefore, it is suggested that ECD be included in the treatment modalities of benign PPS tumors.

The technique of endoscopy-assisted transoral approach (EATA) has improved greatly, which should provide a better alternative for parapharyngeal space (PPS) tumors. Here, we compared curative effects between the resection of parapharyngeal space (PPS) tumors by EATA and external approaches (EAs), including the transcervical, transparotid, and transmandibular approaches. Based on the tumors' position and the relationship with adjacent structures, we selected 20 patients with parapharyngeal space tumor hospitalized in the Second People's Hospital in Shenzhen from January 2008 to December 2013, which were divided into the observation group and the control group with patients' informed consents. In the observation group, the tumors were removed solely by transoral approach under the guidance of endoscopes (EATA), while in the control group, the tumors were resected completely using an external approach (EA). We compared the total removal rate, the operation time, blood loss, postoperative pain, hospitalized time, complication rate, scar, and recurrence between the two groups. All the tumors were completely removed and patients were followed up for 6 months-5 years with no recurrence in either group. There was no significant difference regarding total removal rate, operation time, complication rate, and recurrence rate between the two groups (P > 0.05). However, significant differences were observed in blood loss, hospitalized time, and postoperative pain between the two groups (P < 0.05). PPS tumors could be completely removed by both EATA and EA. However, EATA has advantages of shortened hospitalized time, alleviated blood loss and postoperative pain level, and preservation of facial cosmetic.

To summarize nuances in the surgical management of parapharyngeal space (PPS) tumors aimed to reduce postoperative sequelae without affecting oncologic outcomes. The contemporary trend in surgery of PPS tumors is to develop minimally invasive approaches that allow tumor resection without the need for mandibulotomy or lateral skull base approaches. This can be obtained by refining well established surgical routes like the transcervical, improving those with limited applications like the transoral, and developing novel corridors like the transnasal (or the transoral/transvestibular). Therefore, careful surgical planning is mandatory in order to tailor treatment according to the patient and characteristics of the tumor, in view of a wide and heterogeneous choice of techniques (to be employed alone or in combination). Technical refinements of transcervical and transoral approaches may lead to reduction in the rate of mandibulotomy performed for benign PPS tumors. This is also true when considering the possibility of combined approaches that provide excellent exposure and management of the upper PPS up to the skull base.

Objective To compare the difference of postoperative nursing between endoscopy-assisted transoral approach and transcervical approach in parapharyngeal space tumorectomy. Methods A total of 67 patients with parapharyngeal space tumor in ENT & HN Surgery Department of Beijing Tongren Hospital from April 2003 to November 2015 were selected and assigned to the control group (n=35) and the observation group (n=32). Patients in the control group were treated by transcervical approach, while patients in the observation group were treated by endoscopy-assisted transoral approach. Comparison of postoperative vital signs, wound, diet, time from surgery to discharge, complications, and patient satisfaction of two groups were performed. Statistical analysis was done by test. Results Four cases in the control group and two cases in observation group were observed a body temperature more than 37.5 ℃ (P>0.05). The wounds of patients in the control group were in the neck, and the wound of patients in the observation group were in the oral cavity. The color of drainage fluid of two groups was normal and both were hemorrhagic effusion. The amount of drainage fluid in control group (46.80±5.20) ml was significantly higher than the observation group (15.22±2.04) ml (P<0.05). The drainage time of control group (3.46±0.74) days was more than the observation group (2.22±0.42) days (P<0.05). Patients in the control group was fed liquid or semi liquid diet, while patients in the observation group was fed nasogastric liquid diet. The time from surgery to discharge in the control group (3.63±0.81) days was longer than that in the observation group (2.63±0.49) days (P<0.05). Cases with complications in the control group (seven cases) was significantly higher than that in the observation group (zero case)(P<0.05). Satisfaction score of patients in the control group (3.94±0.73) points was significantly lower than that in the observation group (4.31±0.69) points (P<0.05). Conclusions Endoscopic-assisted transoral approach and transcervical approach are effective treatment for tumors in parapharyngeal space. Endoscopic-assisted transoral approach has more advantages in the aspect of the amount of fluid drainage, drainage time and length of stay, complication rate, and satisfaction of patients. Key words: Nursing; Parapharyngeal space tumor; Endoscope-assisted; Transoral approach; Transcervical approach