Selection of the surgical approach for lesions with parapharyngeal space involvement: A single-center experience on 153 cases

Evaluation of multiparametric MRI differentiating pleomorphic adenoma from schwannoma in parapharyngeal space

PURPOSE

This study aimed to investigate whether multiparametric magnetic resonance imaging (MRI) including dynamic contrast-enhanced (DCE) and diffusion weighted (DW) MRI can differentiate pleomorphic adenoma (PA) from schwannoma in the parapharyngeal space.

METHODS

Forty-six patients with pathologically proven PAs and 47 schwannomas in the parapharyngeal space were enrolled. All patients underwent conventional MRI, and DW-MRI and DCE-MRI were performed in 30 and 33 patients, respectively. Fisher's exact, Mann-Whitney-U tests and Independent samples t-test were used to compare variables between PAs and schwannomas. Multivariate logistic regression analysis was used to examine the diagnostic performance of MRI parameters.

RESULTS

The PAs usually show lobulation sign, posterior displacement of ICA and attached to the parotid gland deep leaf, while bird beak configuration, anterior displacement of ICA and involvement of foramen jugular were more commonly seen in the schwannomas(all p < 0.001). The washout rate of PAs was found to be higher than that of schwannomas (p = 0.035), whereas no significance was found in the other DCE-MRI parameters and in ADCs(p > 0.05). Using a combination of conventional MRI features including lobulation sign, bird beak configuration, direction of internal carotid artery(ICA) displacement and attached to the parotid gland in multivariate logistic regression analysis, sensitivity, specificity, and accuracy in differential diagnosis of PAs and schwannomas were 97.8%, 91.5% and 94.6%, respectively.

CONCLUSION

Conventional MRI can effectively differentiate PAs from schwannomas in the parapharyngeal space with a high diagnostic accuracy. The DCE-MRI and DWI have limited added diagnostic value to conventional MRI in the differential diagnosis.

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.

Management of Parapharyngeal Space Tumors: Clinical Experience with a Large Sample and Review of the Literature

Parapharyngeal space (PPS) tumors are rare, and they account for 0.5-1.5% of all head and neck tumors. This study summarized the findings of large-sample clinical studies of PPS tumors and reported the clinical work-up and management of 177 cases of PPS tumors at our center. This retrospective study included patients treated for PPS tumors between 2005 and 2020 at our center. The basic characteristics, symptoms, surgical approach, complications, and recurrence rates were analyzed. A total of 99 male and 78 female patients, with a mean age of 48.3 ± 15.1 years, were enrolled in this study. The most common symptoms were external or intraoral masses (114 patients, 64%). Surgical management leveraging, a cervical approach, was used for 131 cases (74%). The tumors were benign for 92% (160 cases), with pleomorphic adenoma being the most common (88 cases, 50%). Surgical complications were reported for 31 cases (18%); facial and vocal cord paralyses were the most common. Three cases of recurrence were observed during the follow-up. PPS tumors are rare and present with atypical clinical manifestations. The current study, which involved cases in a large single center, demonstrates the importance of surgical interventions for PPS tumors. The use of endoscopic techniques has further expanded the scope of traditional surgical approaches and demonstrated its advantages in selected cases.

Transoral Approach to Parotid Tumors: A Review of the Literature

Different surgical techniques have been proposed for parapharyngeal space tumors, including transcervical, transparotid, trans-mandibular, infratemporal, and transoral. The choice of the correct approach depends on the size, localization and nature of the tumor. The transoral approach can be used for benign prestyloid masses, such as tumors of the deep lobe of the parotid gland. It guarantees a short hospitalization without skin scars. The narrowed access represents the main limitation of this technique. This review will summarize and analyze the current knowledge about the transoral approach to parotid lesions. Thirty-seven studies were included in a qualitative and quantitative synthesis. The novelty of this review is the quantitative analyses of the clinical data reported in the included studies.

Endoscopy‐assisted transoral approach for parapharyngeal space tumors: Our experience and a systematic review of the literature

Background

Several approaches have been described for the excision of parapharyngeal space tumors (PPSTs). Advances in endoscopy gave a further stimulus to the use of the transoral route.

Aims

We present our experience with the endoscopy-assisted transoral approach (EATA) in this regard and a review of the most recent literature about EATA for PPSTs excision.

Materials and Methods

We retrospectively analyzed our experience and systematically reviewed the literature about the outcomes of this technique.

Results

Seven PPSTs were completely excised, with three of them requiring a combined transcervical approach. Only one case of postoperative wound dehiscence was registered, and the mean length of stay was 3.9 days. Final histopathological examination confirmed the results obtained with preoperative fine-needle aspiration biopsy in all cases and no recurrences were apparent after a mean follow-up of 28.1 months.

Discussion

Magnetic resonance imaging, the modified Mallampati score and the 8 Ts criteria are useful instruments for the choice of the most appropriate surgical approach.

Conclusion

In light of our experience and following other published series in the literature, we believe that EATA may represent a safe and effective approach for the treatment of the majority of PPSTs.

Surgical Treatment of Parapharyngeal Space Salivary Gland Tumor

INTRODUCTION

Parapharyngeal space salivary gland tumors are very rare. The authors sought to examine the clinical features, treatment methods, and treatment results of parapharyngeal space salivary gland tumors in our hospital.

METHODS

The authors retrospectively enrolled 15 patients who were finally diagnosed as having parapharyngeal space salivary gland tumors from January 2010 to January 2021.

RESULTS

All parapharyngeal space salivary gland tumors arose from the prestyloid compartment. This study included 3 males and 12 females. The main symptoms were incidental diagnosis during imaging tests, followed by neck discomfort, oral mass, neck mass, and headache. Surgical methods for parapharyngeal space salivary gland tumors were performed in the following order: transcervical approach (n = 10), transcervical-parotid approach (n = 3), transoral approach (n = 1), and transparotid approach (n = 1). Pleomorphic adenoma was the most common tumor among parapharyngeal space salivary gland tumors.

CONCLUSIONS

In the surgery of parapharyngeal space salivary gland tumors, a transcervical or transcervical-parotid approach was mainly used by predicting the origin site through radiologic examinations.

Pleomorphic Adenoma of the Parotid Gland and the Parapharyngeal Space: Two Diametrically Opposing Surgical Philosophies for the Same Histopathologic Entity?

BACKGROUND

The aim of this study was to investigate the histopathologic findings in parotid and parapharyngeal pleomorphic adenomas and draw conclusions concerning the surgical strategy.

METHODS

Retrospective study of medical charts of patients with resected pleomorphic adenomas (PA) between 2005 and 2020 at two tertiary medical referral centers. Histologic specimens were reexamined by an experienced head and neck pathologist. Patients with insufficient/incomplete data were excluded from our study sample.

RESULTS

A total of 844 patients formed our study sample (291 men, 553 women, average age 48.9 years); 786 cases had a PA in the parotid gland (PG) (93.1%), and the remaining 58 cases had a PA in the parapharyngeal space (PS) (6.9%). Recurrences were detected in 8/844 cases (7/786 in the PG, 1/58 in the PS, 0.94% in total) with a mean follow-up time of 86.7 months (10-189 months) with no statistically significant differences between the study groups (p = 0.527). Our analysis showed that parapharyngeal pleomorphic adenomas are characterized by a lower incidence of an intact anatomical capsule (71.4% vs. 82.6%, p = 0.035) and a remarkably more frequent occurrence of satellite nodules (20.7% vs. 7.5%, p < 0.001).

CONCLUSIONS

The more challenging histopathologic profile of parapharyngeal pleomorphic adenomas points towards the fact that parapharyngeal surgery should remain in the hands of experienced surgeons at high-volume centers.

Development of a cadaveric head and neck cancer model and three-dimensional analysis of margins in surgical navigation-aided ablations

INTRODUCTION

The adequacy of the surgical resection is the main controllable variable that is in the hands of the surgical team. There exists an unmet need to increase the rate of negative margins, particularly in cancers invading the craniofacial area. The study aimed 1) at developing a gross tumor model to be utilized for research, educational, and training purposes and 2) establishing the 3-dimensional relationship between the outer surface of the surgical specimen and tumor surface and test the effect of guiding ablations on cadavers with surgical navigation (SN).

MATERIAL AND METHODS

Seven cadaver heads were employed to create 24 craniofacial tumor models. Simulation of tumor resections was performed by 8 surgeons. Fourteen and 10 resections were performed with and without SN-guidance, respectively. Gross specimens underwent computed tomography and 3-dimensional analysis through dedicated software. Task load was assessed through a validated questionnaire. Tumor model reliability was studied based on visual analogue scale rate by surgeons and radiologists.

RESULTS

SN reduced the rate of margin involvement, particularly by decreasing the percentage of the gross specimen outer surface involvement in areas uncovered by normal bony structures. The workload of SN-aided ablations was found to be medium-to-somewhat-high. Tumor model reliability was deemed satisfactory except for the extension to bony structures.

CONCLUSIONS

A gross tumor model for head and neck cancers involving the craniofacial area was developed and resulted satisfactorily reliable from both a surgical and radiologic standpoint. SN reduced the rate of margin involvement, particularly by improving delineation of bone-uncovered areas.

Management of parapharyngeal space tumors with transparotid-transcervical approach: analysis of prognostic factors related with disease-control and functional outcomes

PURPOSE

Different therapeutic strategies have been developed to improve surgical and functional outcome of parapharyngeal space (PPS) neoplasms. The transparotid-transcervical approach (TTa) is a valid surgical option to manage most PPS tumors. Its short- and long-term disease control and cranial nerve (c.n.) function outcomes have not been discussed extensively.

METHODS

All patients who underwent TTa over a 10-year period at a tertiary academic center were retrospectively reviewed. Data about preoperative imaging, clinical presentation, tumor's size, location and histology, and postoperative oncological and functional results were registered and analyzed.

RESULTS

Sixty patients matched the inclusion criteria. Most of the lesions were benign (71.7%), involved the prestyloid PPS (63.3%) and measured more than 30 mm (75%). Fifty-two (86.7%) lesions were resected en-bloc. Clear margins were achieved in 91.7% of the cases, with positive margins solely associated with malignancy (p = 0.008). Post-operative c.n. function was satisfactory, with X c.n. function significantly associated with the retrostyloid location (p = .00) and neurogenic tumors (p = 0.02). Local disease-control was achieved in 96% of the cases after a median follow-up of 46 (± 19.7-82.0 IQR) months.

CONCLUSIONS

The TTa was safe and effective, achieving a satisfactory local control rate. Nevertheless, malignancies maintain a higher rate of positive margin due to their infiltrative nature and the complex anatomy of the PPS. In such cases, multiportal approaches might be more effective. However, post-operative c.n. function remained satisfactory, irrespective of lesions' size and histopathologic behavior. A higher X c.n. deficit rate was observed in retrostyloid and neurogenic lesions.

Margin status, local control, and disease-specific survival in surgically resected parotid carcinomas with parapharyngeal extension

BACKGROUND

Resection of parotid carcinomas involving the parapharyngeal space is challenging. How this affects tumor margin control, recurrence, and survival is unclear.

METHODS

Patients who underwent resection of parotid carcinomas between 1985 and 2015 at Memorial Sloan Kettering Cancer Center were evaluated for the impact of parapharyngeal extension (PPE) on margin status, local recurrence-free probability (LRFP), and disease-specific survival (DSS).

RESULTS

Out of 214 patients in whom preoperative imaging was available for review, 22 (10.3%) had PPE. Matched by histotypes, carcinomas with PPE had comparable margin positivity (p = 0.479), T classification (p = 0.316), pathologic risk (p = 0.936), and adjuvant therapy (p = 0.617) to those without PPE. The 3-year LRFP was 88.9% versus 95.4% (hazard ratio [HR] 2.23 after adjusting for pT classification, p = 0.342) and the 5-year DSS was 74.2% versus 69.5% (adjusted HR 0.45, p = 0.232) in patients with and without PPE.

CONCLUSION

PPE does not appear to worsen oncologic outcomes in the resection of parotid carcinomas.

Endoscopic-assisted multi-portal compartmental resection of the masticatory space in oral cancer: Anatomical study and preliminary clinical experience

OBJECTIVES

To present an anatomical cadaver dissection study and our preliminary surgical experience with endoscopic-assisted multi-portal compartmental resection of the masticatory space (MS) in locally advanced oral squamous cell carcinoma (OSCC) of the retromolar area.

MATERIALS AND METHODS

Two fresh-frozen cadaver heads were dissected in the Laboratory of Anatomy to define the surgical steps of an endoscopic-assisted multi-portal compartmental approach to the MS. After this preclinical anatomical study, patients affected by locally advanced OSCC originating from the retromolar area with extension to the MS were prospectively enrolled and operated at two Italian referral centers for head and neck cancer between October 2019 and May 2020.

RESULTS

Surgical technique of endoscopic-assisted multi-portal compartmental resection of the MS was preclinically defined step by step in 3 phases: transnasal, transoral/trancervical, and multi-portal. Compartmental resection of the MS was successfully completed in all specimens (4 MSs dissected). The surgical technique was subsequently applied in 3 patients affected by primary OSCC of the retromolar area, providing satisfactory results in terms of negative resection margins and local control.

CONCLUSIONS

Multi-portal compartmental resection of the MS combining the transnasal and transoral/transcervical corridors is technically feasible. Such an approach to the MS in locally advanced OSCC provides different angles of incidence to the target and full control of tumor margins.

The development of a clinical algorithm for the diagnosis of tumours in the parapharyngeal space. A systematic review

INTRODUCTION

Parapharyngeal space (PPS) is defined as a deep space, located around the upper pharynx, in the shape of an inverted pyramid. Primary tumours in this region are rare, accounting for 0.5% of head and neck neoplasms, and most are benign. The objective of this study is to propose a new study algorithm based on a systematic review and our experience.

MATERIALS AND METHODS

A cross-sectional and analytical study was carried out through review of the clinical records of our hospital. Patients with tumours of the parapharyngeal space operated from January 2010 to December 2019 and a systematic review of Pubmed studies from the last 5years were included. We considered clinical signs, diagnostic methods, presumptive diagnosis and histopathological findings. Statistical analysis was performed with STATA v.14 software.

RESULTS

53 of our cases and 1392 from the review were included. The clinical algorithm showed a sensitivity of 76.4% and a specificity of 96.3%, with an AUC of 0.57 for diagnosis.

DISCUSSION

Complementary radiological examinations are essential in the topographic diagnosis of the tumour. Angio-MRI links the tissue of origin of the tumours and provides the highest diagnostic certainty. FNA has some disadvantages in PPS, but it is useful in some patients.

CONCLUSION

The proposed algorithm contributes to obtaining excellent results in the management of these tumours because it turned out to be effective in diagnosis, and this enables improved surgical planning.

The intraoral growth patterns of parapharyngeal tumors: A proposed classification system

OBJECTIVE

Nearly half of parapharyngeal space (PPS) tumors present as an intraoral mass, which is diagnostically challenging. In this study, we studied whether preoperative growth patterns were associated with histopathological diagnosis for planning surgery.

METHODS

We performed a cross-sectional study in patients with PPS tumors. A simplified classification scheme based on intraoral tumor growth patterns (patterns 1 and 2) was then proposed. In pattern 1, tumors bulge submucosally to the oropharynx from the soft palate, with the center convexity above the uvula. In pattern 2, tumors bulge submucosally to the oropharynx from the lateral oropharynx wall, with the center convexity below the uvula. The association of this classification with postoperative histopathological diagnosis and surgical-related events was studied.

RESULTS

Twenty-two patients were enrolled in this study (12 with pattern 1, 10 with pattern 2). Of these, 91.7% (11/12) of pattern 1 tumors were salivary gland tumors (P < .001), and 90% (9/10) of pattern 2 tumors were neurogenic (P < .001). Pattern 2 tumors had fewer bleeding complications or needed external approaches when a transoral approach was chosen.

CONCLUSIONS

This new classification of PPS tumors facilitates the prediction of salivary gland and neurogenic tumors and can improve the accuracy of preoperative radiologic diagnosis. This system will be helpful for planning surgical interventions, such as implementing transoral approaches.

Nodular Oncocytic Hyperplasia of Bilateral Parotid Glands With Parapharyngeal Space Extension

Oncocytic tumors comprise a group of rare benign neoplasm of salivary glands, accounting for less than 1% of all salivary gland tumors. Nodular oncocytic hyperplasia characterized by multiple unencapsulated oncocytic nodules in the salivary glands is an extremely rare condition. We report a case of bilateral nodular oncocytic hyperplasia of parotid glands with parapharyngeal space extension in an 80-year-old woman whose initial presentation was recurrent parotitis. Our case may be the first report of nodular oncocytic hyperplasia in the parapharyngeal space, arising from the parotid gland. The patient underwent total parotidectomy and excision of parapharyngeal tumors using a transparotid transcervical approach, and at the 2-year follow-up, no evidence of recurrence was found.