From craniofacial resection to endonasal endoscopic removal of malignant tumors of the anterior skull base

Interdisciplinary Management of Skull Base Tumors

OBJECTIVE

Endoscopic endonasal skull base surgery has gained acceptance worldwide. Comparative analysis has demonstrated that endoscopic skull base surgery may have advantages for many pathologies of the anterior skull base, e. g., sinonasal malignant tumors; pathologies of the central skull base, e. g., pituitary adenomas, craniopharyngiomas; well-selected cases of planum sphenoidale and tuberculum sellae meningiomas; or for clival lesions, e. g., chordomas, chondrosarcomas, or selected meningiomas. Over the past three decades, interdisciplinary surgical teams, consisting of otolaryngologists and neurosurgeons, have provided detailed anatomical knowledge, suggested new approaches or modifications of established surgical techniques, and offered continued surgical education.

METHOD

A review of pertinent literature was conducted with an emphasis on interdisciplinary endoscopic surgery of skull base lesions.

RESULTS

Based on the authors̓ surgical experience in two different interdisciplinary endoscopic skull base centers, the authors classify approaches for endoscopic endonasal skull base surgery, describe indications, and key anatomic landmarks for common pathologies, and highlight surgical techniques to avoid complications.

CONCLUSION

Interdisciplinary endonasal endoscopic surgery combines surgical expertise, improves resection rates for many pathologies, and minimizes morbidity by reducing the incidence of surgical complications.

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field.

METHODS

In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication.

RESULTS

The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention.

CONCLUSION

As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses.

Maxillary Swing Approach for Central Skull Base Lesions in Extreme Situations: A Single-Institutional Case Series

OBJECTIVE

Radical resection of complex lesions occupying multiple compartments at the central skull base remains a significant challenge, since surgical outcomes may be compromised by insufficient exposure and inappropriate techniques. However, the efficiency of the maxillary swing approach for these lesions has not been sufficiently evaluated. Careful assessment of lesion characteristics must be performed when selecting the appropriate procedure.

METHODS

Between May 2006 and February 2017, 17 patients underwent resection of extensive lesions in the central skull base using the maxillary swing approach. As shown in the representative cases, data regarding clinical findings and technical considerations were reviewed.

RESULTS

Complete resection was achieved in all patients. The pathological findings were diverse, and the majority were schwannomas (9 cases, 52.94%), followed by meningiomas (World Health Organization II) (3 cases, 17.65%). Complications were managed as described in the case illustrations, and symptoms improved with time. The follow-up duration ranged from 62 to 192 months (median, 114 months), while 2 patients were lost to the follow-up. No mortality was observed. Two patients who experienced malignancy relapse were still under observation due to their asymptomatic status.

CONCLUSIONS

Our preliminary results suggest that the maxillary swing approach can be an alternative option for managing extreme cases, such as large, extensive, hypervascularized masses with fibrous or calcified consistency, or for recurrent lesions in the central skull base. En bloc resection can be successfully obtained, resulting in long-term local control.

Large Cell Neuroendocrine Carcinoma in the Sinonasal Cavity with Large Intracranial Extension Treated with Endonasal Endoscopic and Transcranial Combined Surgery: A Case Report

Large cell neuroendocrine carcinoma (LCNEC) is a rare malignant tumor that typically arises in the lungs. It is especially rare in the sinonasal cavity, and treatment has not been established. In this study, we present the case of a 56-year-old woman with a large sinonasal LCNEC that extended into her brain. We performed endonasal endoscopic and transcranial combined surgery followed by chemoradiation therapy. The combined surgery enabled us to approach and remove the extensive tumor from two different directions at one time less invasively. We have achieved good tumor control for 18 months so far.

The neurosurgical management of sinonasal malignancies involving the anterior skull base: a 28-year experience at The MD Anderson Cancer Center

OBJECTIVE

Sinonasal malignancies that extend to the anterior skull base frequently require neurosurgical intervention. The development of techniques for craniofacial resection revolutionized the management of these neoplasms, but modern and long-term data are lacking, particularly those related to the incorporation of endoscopic techniques and novel adjuvant chemotherapeutics into management schema. The present study was performed to better define the utility of surgical management and to determine factors related to outcome.

METHODS

Patients who underwent surgery between 1993 and 2020 were included in this retrospective cohort study. Only patients with greater than 6 months of clinical and radiological follow-up were included. Outcome measures included progression, survival, and treatment-related complications.

RESULTS

Two hundred twenty-five patients were included. The mean clinical follow-up was 6.5 years. The most common histological diagnosis was olfactory neuroblastoma (33%). Overall, metastatic disease and brain invasion were present in 8% and 19% of patients, respectively, at the time of surgery. A lumbar drain was used in 54% of patients. When stratified by decade, higher-stage disease at surgery became more frequent over time (15% of patients had metastatic disease in the 3rd decade of the study period vs 4% in the 1st decade). Despite the inclusion of patients with progressively higher-stage disease, median overall survival (OS) remained stable in each decade at approximately 10 years (p = 0.16). OS was significantly worse in patients with brain invasion (p = 0.006) or metastasis at the time of surgery (p = 0.014). Complications occurred after 28% of operations, but typically resulted in no long-term negative sequelae. Use of a lumbar drain was a significant predictor of complications (p = 0.02). Permanent ophthalmological disabilities were observed after 4% of surgical procedures. One patient died during the perioperative period. Finally, major complications (Clavien-Dindo grade ≥ IIIb) decreased from 27% of patients in the 1st decade to 10% in the 3rd decade (p = 0.007).

CONCLUSIONS

The surgical management of sinonasal malignancies with anterior skull base involvement is effective and generally safe. Surgical management, however, is only one facet of the overall multimodal management paradigms created to optimize patient outcomes. Survival outcomes have remained stable despite more extensive disease at surgery in patients who have presented in recent decades. The safety of such surgery has improved over time owing to the incorporation of endoscopic surgical techniques and the avoidance of lumbar spinal drainage with open resection.

The combined coronal-transconjunctival approach: an innovative surgical access for orbital exenteration in craniofacial resection

Malignant tumours arising in the paranasal sinuses or maxilla usually spread to the surrounding regions. The skull base and the anterior cranial fossa are frequently affected as well. When the resection of a tumour involves an orbital exenteration, a transconjunctival-perilimbic incision can be added to a coronal approach in order to preserve the eyelids and the conjunctiva, avoiding cutaneous midfacial incisions. Patients with a diagnosis of malignant tumour affecting the orbit, upper jaw, paranasal sinuses, and/or anterior skull base were eligible for this technique. Tumoural invasion of the eyelids, conjunctiva, lacrimal system, or surrounding skin was considered a contraindication for this technique. A retrospective study of the clinical records was performed and age, type of tumour, location, and reconstructive technique were evaluated. Eight patients referred to the study department between 2015 and 2019 were selected. All patients underwent craniofacial surgery and orbital exenteration. The transconjunctival-perilimbic approach was combined with a coronal incision in all cases. In our experience, the transconjunctival-perilimbic approach to orbital exenteration proposed in this paper can be used successfully in skull base surgery. Combined with a coronal and transmandibular approach, it allows wide access to the facial skeleton/anterior skull base while avoiding skin incisions in the midface.

Transfacial Exposures of the Anterior Skull Base and Cervical Spine: Straightforward "Line-of-Sight" Algorithm for Selection of Approach

ABSTRACT

Surgical treatment for tumors of the skull base remains gross total resection with microscopic negative margins. Sufficient surgical access is paramount to adequate treatment but must be balanced with patient morbidity and protection of vital neurovascular structures. While endoscopic surgery has made transfacial access less common, there are still indications for open transfacial exposure including tumors that involve facial soft tissues, the palate, anterolateral frontal sinus, dural involvement lateral to the mid-pupillary line, tumor recurrence/repeat resection, and/or lack of access to endoscopic equipment or expertise. The authors present a "line-of-sight" algorithm for selection of approach, discuss pre-operative planning, review selected clinical experiences, and discuss the role of microsurgery and prevention of complications.

Management of sinonasal adenocarcinomas with anterior skull base extension

INTRODUCTION

Sinonasal adenocarcinomas (SNAC) are rare and heterogeneous. Management of SNAC follows a rather standardized and internationally accepted paradigm. Several refinements have been introduced during the last decade.

METHODS

A narrative review of most updated literature on SNACs has been conducted.

RESULTS

SNACs are classified as intestinal-type and non-intestinal-type, which are further categorized according to grade. Preoperative work-up should include magnetic resonance imaging (or contrast-enhanced computed tomography as a secondary or complementary choice) and biopsy under general anesthesia, or under local anesthesia in case of a history of exposure to wood and/or leather dust. Positron emission tomography, neck ultrasound, and fine-needle aspiration cytology are indicated in selected cases. Surgery represents the most common upfront modality of treatment and is usually accomplished via a transnasal endoscopic approach. Adjuvant radiation therapy is indicated for high-grade, locally advanced tumors and/or in case of margins involvement. Neoadjuvant chemotherapy with cisplatin, 5-fluorouracil and leucovorin may offer high response rates and long-term control in a subgroup of patients affected by intestinal-type adenocarcinoma, and in particular in those whose tumors harbor a functional p53 protein. Most of the bio- and immune-therapeutic potentials on SNACs still remain theoretical, and no clinical data are currently available.

CONCLUSIONS

Management of SNAC consists of histological diagnosis, radiological staging, radical surgery, and adjuvant radiation therapy. Neoadjuvant chemotherapy can be indicated in selected cases. The role of biotherapy and immune therapy still needs to be elucidated.

Endoscopic-assisted maxillectomy: Operative technique and control of surgical margins

BACKGROUND

When amenable to radical excision, cancer involving the maxilla is typically treated with maxillectomy followed by adjuvant therapy. Posterior tumor extension beyond the maxillary box leads to the invasion of complex areas, where achieving clear margins may be challenging.

METHODS

Patients undergoing endoscopic-assisted maxillectomy for nasoethmoidal, maxillary, or hard palate cancer between 2007 and 2017 were included in the study. Surgical technique, margin status, and recurrences were analyzed. Extension of posterior resection was classified in 3 types (type 1: resection of the pterygopalatine fossa; type 2: resection of the pterygoid plates and related muscles; type 3: resection of the upper parapharyngeal space). The analysis of putative risk factors for involvement of margins and local recurrence was performed with special focus on the posterior and medial margin.

RESULTS

The study included 79 patients (75 with available follow-up; mean: 20.6 months, range: 6-101 months), 37 (46.8%) of whom underwent type 1 resection, 34 (43.0%) type 2, and 8 (10.1%) type 3. According to pT category, 57 (72.2%) tumors were classified as T4a/T4b. Posterior and medial clear margins were achieved in 76/79 (96.2%) and 75/79 (94.9%) patients, respectively. T4b category, extension to the ethmoid, sphenoid sinus, pterygoid process, orbital cavity, and premaxillary tissues were significantly associated with a higher rate of margin involvement. None of the factors was significantly associated with medial margin involvement.

CONCLUSION

Endoscopic-assisted maxillectomy combines several refinements including the facilitated detachment of the maxilla from the skull base and precise delineation of the posterior and medial margins of resection.

Impact of endoscopic craniofacial resection on simulated nasal airflow and heat transport

BACKGROUND

Endoscopic craniofacial resections (CFR) are performed for extensive anterior skull base lesions. This surgery involves removal of multiple intranasal structures, potentially leading to empty nose syndrome (ENS). However, many patients remain asymptomatic postoperatively. Our objective was to analyze the impact of CFR on nasal physiology and airflow using computational fluid dynamics (CFD). This is the first CFD analysis of post-CFR patients.

METHODS

Three-dimensional sinonasal models were constructed from 3 postoperative images using Mimics^TM . Hybrid computational meshes were created. Steady inspiratory airflow and heat transport were simulated at patient-specific flow rates using shear stress transport k-omega turbulent flow modeling in Fluent^TM . Simulated average heat flux (HF) and surface area where HF exceeded 50 W/m² (SAHF50) were compared with laminar simulations in 9 radiographically normal adults.

RESULTS

Three adults underwent CFR without developing ENS. Average HF (W/m² ) were 132.70, 134.84, and 142.60 in the CFR group, ranging from 156.24 to 234.95 in the nonoperative cohort. SAHF50 (m² ) values were 0.0087, 0.0120, and 0.0110 in the CFR group, ranging from 0.0082 to 0.0114 in the radiographically normal cohort. SAHF50 was distributed throughout the CFR cavities, with increased HF at the roof and walls compared with the nonoperative cohort.

CONCLUSION

Average HF was low in the CFR group compared with the nonoperative group. However, absence of ENS in most CFR patients may be due to large stimulated mucosal surface area, commensurate with the nonoperative cohort. Diffuse distribution of stimulated area may result from turbulent mixing after CFR. To better understand heat transport post-CFR, a larger cohort is necessary.

Transnasal endoscopic surgery in selected nasal-ethmoidal cancer with suspected brain invasion: Indications, technique, and outcomes

BACKGROUND

In nasal-ethmoidal malignancies, brain involvement is associated with dismal prognosis.

METHOD

Patients undergoing endoscopic resection with transnasal craniectomy and subpial dissection (ERTC-SD) for brain-invading nasal-ethmoidal cancer between 2008 and 2016 were included. Complications were analyzed in all patients, whereas oncological outcomes only in patients with pathological brain invasion. The prognostic impact of previous treatments, brain edema, and histology was assessed. Hospitalization ratio was calculated.

RESULTS

Nineteen patients received ERTC-SD and 11 had pathological-proven brain invasion. Histologies were 6 olfactory neuroblastomas (ONB), 3 neuroendocrine carcinomas, and 2 intestinal-type adenocarcinomas. Mean follow-up was 21.9 months. Three-year overall, local recurrence-free, and distance recurrence-free survivals were 65.5%, 81.8%, and 68.2%, respectively. Overall and distant recurrence-free survivals were significantly better in patients with ONB (P = 0.032 and P = 0.013, respectively). Hospitalization ratio was 4.1%. Complication rate was 10.5%.

CONCLUSION

In selected nasal-ethmoidal tumors with brain invasion, ERTC-SD can provide good local control, satisfactory survival, and limited morbidity.

Craniofacial resection of malignant tumors of the anterior skull base: a case series and a systematic review

BACKGROUND

Craniofacial resection (CFR) is still considered as the gold standard for managing sinonasal malignancies of the anterior skull base (ASB), while endoscopic approaches are gaining credibility. The goal of this study was to evaluate outcomes of patients who underwent CFR at our institution and to compare our results to international literature.

METHOD

Retrospective analysis of all patients undergoing CFR between 1995 and 2017, and systematic literature review according to the PRISMA statement.

RESULTS

Forty-one patients with sinonasal malignancy (81% with stage T4) of the ASB were included. There was no operative mortality. Complications were observed in 9 cases. We obtained 100% follow-up with mean observation of 100 months. Disease-specific survival rates were 90%, 74%, and 62% and recurrence-free survival was 85% at two, 72% at five, and 10 years follow-up, respectively. CFR as primary treatment, en bloc resection, and resection with negative margins correlated to better survival. Recursive partition analysis identified the latter as the most important prognostic factor, regardless of surgical technique. The relative risk of non-radicality was significantly higher after piecemeal resection compared to en bloc resection. Compared to 15 original articles, totaling 2603 patients, eligible for review, the present study has the longest follow-up time, the second highest 5-year OS, and the third highest 5-year DSS, despite having a higher proportion of patients with high-stage disease.

CONCLUSION

CFR in true en bloc fashion can still be considered as the treatment of choice in cases of advanced-stage sinonasal malignancies invading the ASB.

Access to the Skull Base - Maxillary Swing Procedure - Long Term Analysis

Background:

Skull base is difficult to approach surgically due to its complex anatomy. A number of procedures that is endoscopic, microscopic, and open approaches have been used. The maxillary swing approach provides a wide exposure to the surgeon for better oncological clearance.

Patients and Methods:

A total of 62 patients with varied etiologies involving the skull base region were operated with maxillary swing procedure over a period of 15 years from 2001 to 2016 in plastic surgery department at a single institution.

Results:

There was no recurrence in the follow-up period. One patient had palatal fistula and one patient had mild nasal mucosal atrophy. None of the patients had malocclusion in the postoperative period. The minimum follow-up period was 24 months.

Conclusion:

Maxillary swing procedure provides excellent exposure to skull base, and most of the tumors involving this region can be effectively excised with minimal morbidity to the patient.

Combined Endoscopic and Open Approaches in the Management of Sinonasal and Ventral Skull Base Malignancies

Combined transcranial and endoscopic endonasal approaches remain useful in the treatment of ventral skull base malignancies. The extended bifrontal transbasal approach provides wide access to the anterior ventral skull base and paranasal sinuses without transfacial incisions. In more extensive lesions, the bifrontal transbasal approach can then be combined with an endoscopic endonasal approach (EEA) from below. This article reviews the indications, surgical technique, and operative nuances of combined transbasal and EEA (cranionasal) approaches for the surgical management of ventral skull base malignancies.

Extent of Endoscopic Resection for Anterior Skull Base Tumors: An MRI-Based Volumetric Analysis

Objective  To determine the volume of ventral skull base tumor removed following endoscopic endonasal (EEA) resection using MRI-based volumetric analysis and to evaluate the inter-rater reliability of such analysis. Design  Retrospective case series. Setting  Academic tertiary care hospital. Participants  EEA patients November 2012 to August 2015. Main Outcome Measures  Volumetric analysis of pre- and immediately postoperative MR imaging was performed independently by two investigators. The percentage of total tumor resected was evaluated according to resection goal and tumor type. Results  A total of 39 patients underwent resection. Intraclass correlation coefficients between the raters were 0.9988 for preoperative and 0.9819 for postoperative images. Tumors (and average percentage removed) included 17 nonsecreting pituitary adenomas (95.3%), 8 secreting pituitary adenomas (86.2%), 4 meningiomas (81.6%), 3 olfactory neuroblastomas (100%), 2 craniopharyngiomas (100%), 1 large B-cell lymphoma (90.5%), 1 germ cell neoplasm (48.3), 1 benign fibrous connective tissue mass (93.4%), 1 epidermoid cyst (68.4%), and 1 chordoma (100%). For tumors treated with intent for gross total resection, 96.9 ± 4.8% was removed. Conclusion  EEAs achieved tumor resection rates of ∼97% when total resection was attempted. The radiographic finding of residual tumor is of uncertain clinical significance. The volumetric analysis employed in this study demonstrated high inter-rater reliability and could facilitate further study.

Imaging in Endoscopic Cranial Skull Base and Pituitary Surgery

Endoscopic endonasal approaches have widely accepted techniques for managing benign and malignant processes along the entire ventral skull base with similar or better results compared with open procedures, but with lower rates of complication. Managing pathology affecting the skull base can be challenging because of complex anatomy and the proximity of critical neurovascular structures. Postoperative imaging can be challenging, because of surgical alterations of normal anatomy and the now common use of complex reconstruction techniques. Understanding the normal imaging appearance of skull base reconstruction is important for accurate postoperative interpretation and delineation between normal reconstructive tissue and recurrent neoplasm.

An Algorithm for Surgical Approach to the Anterior Skull Base

OBJECTIVE

To characterize our experience with the surgical management of anterior skull base malignancy, and to propose an algorithm for surgical approach to anterior skull base malignancies.

DESIGN

Retrospective review.

SETTING

Academic cranial base center.

PARTICIPANTS

Sixty-seven patients who underwent resection of paranasal sinus or anterior skull base malignancy with an endoscopic, cranioendoscopic, or traditional anterior craniofacial approach.

OUTCOME MEASURES

Complications, recurrence, and survival.

RESULTS

There were 48 males and 19 females, ranging from 6 to 88 years old. There were three groups: endonasal endoscopic resection (n = 10), cranioendoscopic resection (n = 12), and traditional craniofacial resection (n = 45). The most common tumor pathologies included esthesioneuroblastoma, squamous cell carcinoma, and sinonasal undifferentiated carcinoma. Patients with T3/T4 disease were less likely to undergo endoscopic resection (p = 0.007). The 5-year disease-free survival was 82.1% overall, with no statistically significant differences among approaches. There were no differences in orbital complications, meningitis, or cerebrospinal fluid leak. Use of a transfacial incisions predisposed patients to surgical site infection and sinocutaneous fistulae. An algorithm for surgical approach was developed based on these results.

CONCLUSION

Sinonasal and skull base malignancies can be safely surgically addressed via several approaches. Surgical approach should be selected algorithmically based on preoperative clinical assessment of the tumor and known postoperative complication rates.

Advantage of Extended Craniofacial Resection for Advanced Malignant Tumors of the Nasal Cavity and Paranasal Sinuses: Long-Term Outcome and Surgical Management

OBJECTIVE

Craniofacial resection (CFR) for advanced sinonasal malignant tumors (SNMTs) is mandatory for radical resection. Surgeons must be aware of perioperative complications and long-term outcome because this procedure is extremely invasive, especially when the tumor involves the anterior skull base.

METHODS

Thirty-eight consecutive surgical patients with advanced SNMT of T4 stage or Kadish stage C (31 men and 7 women; mean age, 55 years; range: 19-76 years) treated with CFR in the past 28 years were followed up for 59.4 months. In cases of unilateral orbital extension, en-bloc resection was achieved using several neurosurgical techniques (extended CFR) from 2005 onwards. Herein, we evaluated the safety and effectiveness of surgery by comparing survival data between 2 time periods (first stage: 1984-2004, second stage: 2005-2012).

RESULTS

Squamous cell carcinoma was the most common histological type observed (65.8%), followed by esthesioneuroblastoma (15.8%). Using a combination of adjuvant radiation therapy, the 5-year overall survival and the 5-year disease-specific survival rates were 55.5% and 59.4%, respectively. Sarcomatous histology was a poor prognostic factor. The 5-year disease-specific survival rate was 48.9% in the first stage and improved to 82.1% in the second stage (P = 0.057); this was related to improvements in local control rate.

CONCLUSIONS

CFR and postoperative radiotherapy are safe and effective for treating advanced SNMTs. Extended CFR, including radical orbital exenteration, may contribute to good long-term outcomes. A diverse surgical team may help perform radical resection and reconstruction in patients with advanced tumors.