Tumors of the skull base: outcome and survival analysis of 77 cases

Lateral Skull Base and Auricular Reconstruction

Reconstruction of the lateral temporal bone with adequate functional and cosmetic outcomes depends on a multidisciplinary approach including the head and neck surgeon, reconstructive surgeon, neurotologist, and anaplastologist. Approaching the defect includes consideration of the location, tissue type, function, and patient/tumor characteristics. Anatomic limitations due to prior therapy also play an important role in reconstructive choices. Here, we review contemporary literature regarding the reconstruction of this complex region.

Microsurgical free flaps for skull base reconstruction following tumor resection: Available techniques and complications

INTRODUCTION

Resection of malignant tumors located in the anterior and middle fossae of the skull base requires thorough anatomical knowledge, as well as experience regarding the possible reconstructive options to resolve the resulting defects. The anatomical and functional relevance of the region, the complexity of the defects requiring reconstruction and the potential complications that can occur, represent a true challenge for the surgical team. The goal of this study is to describe the microsurgical reconstructive techniques available, their usefulness and postoperative complications, in patients with malignant tumors involving the skull base.

MATERIALS AND METHOD

This observational, retrospective study, included all patients who underwent surgery for malignant craniofacial tumors from January 1st, 2009 to January 1st, 2019 at a University Hospital in Argentina. Only patients who required reconstruction of the resulting defect with a free flap were included.

RESULTS

Twenty-four patients required reconstruction with FF; 14 were male (58.3%) and mean age was 54.9 years. Sarcoma was the most frequent tumor histology. Free flaps used were the following: anterolateral thigh, rectus abdominis, radial, latissimus dorsi, iliac crest and fibular. Complications occurred in 6 cases and no deaths were reported in the study group.

CONCLUSION

Free flaps are considered one of the preferable choices of treatment for large skull base defects. In spite of the complexity of the technique and the learning curve required, free flaps have shown to be safe, with a low rate of serious complications. For these patients, the surgical resolution should be performed by a multidisciplinary team.

Different Approaches in Skull Base Surgery Carry Risks for Different Types of Complications

Complications are not uncommon in the complex field of skull base surgery. The intrinsic relationship of lesions in this region to important neurovascular structures, dura mater, and bone may lead to significant morbidity and mortality. The evolution of endoscopic endonasal surgery has had a significant impact on this field as a less invasive option for treatment of selected lesions, but major morbidity may still occur; moreover, endoscopic approaches have been associated with higher rates of some specific complications, such as cerebrospinal fluid leaks. Based on a presented case report, the authors discuss the management of various complications associated with different approaches for resection of skull base malignancies, including epidural and intradural pneumocephalus, subdural hematoma, and subdural empyema. Important lessons learned by the senior author throughout more than 30 years of his skull base surgery practice are highlighted. The inherent risk of complications in skull base surgery emphasizes the importance of their avoidance, prevention, and learning from one's unfavorable experience so as not to repeat them.

Orbital Extenteration Defects: Ablative and Reconstructive Flowchart Proposal

ABSTRACT

Orbital exenteration is a radical and disfiguring operation. It is still under debate the absence of correlation between the term describing the resulting orbital defect and the type of reconstruction. Authors' goal was to propose a consistent and uniform terminology for Orbital Exenteration surgery in anticipation of patients' tailored management. Twenty-five patients who underwent orbital exenteration between 2014 and 2020 were reviewed. A parallel comprehensive literature review was carried on. Five different types of orbital exenteration where outlined. Multiple reconstructive procedures were enclosed. An algorithm for orbital reconstruction was proposed based on anatomic boundaries restoration. Eyelid removal was first considered as an independent reconstructive factor, and both orbital roof and floor were indicated as independent reconstructive goals, which deserve different defect classification. In our opinion, this algorithm could be a useful tool for patient counseling and treatment selection, which might allow a more tailored patient care protocol.

LEVEL OF EVIDENCE

Level III.

Interdisciplinary management of skull base surgery

Skull base surgery remains one of the challenging areas in the field of cranio-maxillofacial surgery, otolaryngology and neurosurgery. Subsequent reconstruction of bone and soft tissue are an essential component to restore function and appearance after ablative surgery. Establishment of interdisciplinary tumor boards with presentation of the individual patient cases have become standard. Multiplanar reconstruction using MRI or CT imaging techniques combined with virtual 3D planning allow precise planning of the procedures. Intraoperative navigation helps for complete resection of malignant findings with safety margins; surgical approaches provide a good overview of the surgical site. Reconstruction using local flaps have a low complication rate with equally reliable results in reconstruction of small tissue defects. Free flap surgery makes reconstruction of large tissue defects possible. Alloplastic materials are alternatively used for reconstruction of bone defects. Based on selected patients, treatment algorithms and standard surgical procedures in extracerebral skull base surgery will be illustrated. Current techniques and new approaches will be discussed with emphasize on hard and soft tissue reconstruction.

Chimeric Anterolateral Thigh Flap in Skull Base Reconstruction: A Case-Based Update and Literature Review

Oncologic and traumatic neurosurgery may have to cope with the issue of skull base defects, which are associated with increased risk of meningitis, epidural abscess and cerebro-spinal fluid (CSF) leak. The aim of skull base reconstruction is to repair the dural exposure and to separate the intracranial contents from the nonsterile sino-nasal cavities and extracranial space. Currently, many different surgical techniques have been described, and one of the most performed is the use free flap. In the present paper we performed a case-based update and literature review of the use of chimeric anterolateral thigh free flap harvested from rectus femoris, reporting the case of a 68-year-old man with recurrent spheno-ethmoidalis plane meningioma.

Surgical Management of Skull Base Osteoradionecrosis in the Cancer Population - Treatment Outcomes and Predictors of Recurrence: A Case Series

BACKGROUND

Skull base osteoradionecrosis (ORN) is a challenging treatment-related complication sometimes seen in patients with cancer. Although ORN management strategies for other anatomic sites have been reported, there is a paucity of data guiding the management of skull base ORN.

OBJECTIVE

To report a single-center tertiary care series of skull base ORN and to better understand the factors affecting ORN recurrence after surgical management.

METHODS

We conducted a retrospective cohort study of patients with skull base ORN treated at our center between 2003 and 2017. Univariate and multivariate binary logistic regressions were performed to identify predictors of recurrence.

RESULTS

A total of 31 patients were included in this study. The median age at ORN diagnosis was 61.1 yr (range, 32.8-84.9 yr). Of these 31 patients, 15 (48.4%) patients were initially treated medically. All 31 patients underwent surgery. Three (14.3%) of 21 patients treated with a free flap and 4 (50.0%) of 8 patients who underwent primary closure experienced recurrence. Cox regression analysis revealed that reconstruction with local tissue closure (P = .044) and ongoing treatment for active primary cancer (P = .022) were significant predictors of recurrence. The median overall survival from index surgery for ORN treatment was 83.9 mo. At 12-mo follow-up, 78.5% of patients were alive.

CONCLUSION

In this study, we assess the outcomes of our treatment approach, surgical debridement with vascularized reconstruction, on recurrence-free survival in patients with skull base ORN. Further studies with larger cohorts are needed to assess current treatment paradigms.

Surgical management of carcinomas of the infratemporal fossa and skull base: patterns of failure and predictors of long-term outcomes

OBJECTIVE

Infratemporal fossa (ITF) tumors are unique in histological characteristics and difficult to treat. Predictors of patient outcomes in this context are not known. The objective of this study was to identify independent predictors of outcome and to characterize patterns of failure in patients with ITF carcinoma.

METHODS

All patients who had been surgically treated for anterolateral skull base malignancy between 1999 and 2017 at the authors' institution were retrospectively reviewed. Patient demographics, preoperative performance status, tumor stage, tumor characteristics, treatment modalities, and pathological data were collected. Primary outcomes were disease-specific survival (DSS) and local progression-free survival (LPFS) rates. Overall survival (OS) and patterns of progression were secondary outcomes.

RESULTS

Forty ITF malignancies with skull base involvement were classified as carcinoma. Negative margins were achieved in 23 patients (58%). Median DSS and LPFS were 32 and 12 months, respectively. Five-year DSS and OS rates were 55% and 36%, respectively. The 5-year LPFS rate was 69%. The 5-year overall PFS rate was 53%. Disease recurrence was noted in 28% of patients. Age, preoperative performance status, and margin status were statistically significant prognostic factors for DSS. Lower preoperative performance status and positive surgical margins increased the probability of local recurrence.

CONCLUSIONS

The ability to achieve negative margins was significantly associated with improved tumor control rates and DSS. Cranial base surgical approaches must be considered in multimodal treatment regimens for anterolateral skull base carcinomas.

Current Results of Surgical Treatment of Craniopharyngiomas: The Impact of Endoscopic Endonasal Approaches

Surgery is the main treatment option for the management of craniopharyngiomas. Transcranial microsurgical approaches, such as pterional and subfrontal approaches, have constituted the classic operative strategy for resection of these tumors. However, the development of endoscopic endonasal approaches has revolutionized the treatment of craniopharyngiomas in the last 15 years, and endoscopic resection is favored for most craniopharyngiomas. In this article, we discuss our experience with the management of craniopharyngiomas and review the current results of the surgical treatment of those tumors, including discussion of goals of surgery, complications, recurrences, and the role of adjuvant treatment.

Survival outcomes in locally advanced cutaneous squamous cell carcinoma presenting with clinical perineural invasion alone

BACKGROUND

Cutaneous squamous cell carcinomas (CSCC) involving the head and neck are common, but initial presentation or recurrence limited to the cranial nerves is rare.

METHODS

We conducted a retrospective study of 21 patients with clinical perineural invasion (PNI) from CSCC and no measurable disease by RECIST 1.1. Patients treated with radiotherapy or chemoradiotherapy were included.

RESULTS

The median time from symptom onset until diagnosis was 13.0 months (2.6-83.1). All patients received radiotherapy. Fourteen received concurrent systemic therapy. The median follow-up time was 30.5 months (1.1-106.0). Ten patients recurred, with the majority being locoregional. The 2-year overall survival rate was 85%. The median progression-free survival (PFS) was 21.5 months with an estimated 2-year PFS of 44.5% (95%CI: 22.3-66.8).

CONCLUSIONS

CSCCs with clinical PNI alone are difficult to diagnose and can have a long interval between appearance of symptoms and diagnosis. They can successfully be treated with chemoradiotherapy. However, many patients still suffer from locoregional recurrences.

Short-term survival in extensive craniofacial resections

OBJECTIVES

Craniofacial resection (CFR) procedures for craniofacial tumors with cranial extension are often extensive. Although CFRs may yield good oncological results, there are concerns about high perioperative morbidity and mortality. This study aimed to determine risk factors for perioperative mortality after open CFR in terms of deaths occurring during index hospitalizations.

METHODS

We conducted a retrospective analysis of CFRs conducted at a tertiary oncology hospital from May 2009 through December 2018.

RESULTS

Our analysis included data from the medical records of 102 patients, the majority of whom were male (n=74, 72.5%). The mean age was 61 years (±18.3 years). Skin malignancies (n=64, 63.4%) accounted for nearly two-thirds of the treated tumors, and most of these were squamous cell carcinoma. Postoperative medical complications occurred in 33 patients (33%), and surgical complications occurred in 48 (47%). Multivariate analysis revealed the only independent risk factors for perioperative deaths to be the presence of intracranial tumor extension on preoperative imaging (hazard ratio [HR]=4.56; 95% confidence interval [CI]: 1.74-11.97; p=0.002) and the unexpected emergence of postoperative neurological dysfunction (HR=10.9; 95% CI: 2.21-54.3; p=0.003).

CONCLUSIONS

In our study, factors related to tumor extension were associated with a higher risk of perioperative death.

Advances in the management of primary bone sarcomas of the skull base

Skull base primary malignancies represent a heterogeneous group of histologic diagnoses and sarcomas of the skull base are specific malignant tumors that arise from mesenchymal cells and can be classified by site of origin into bony and soft tissue sarcomas. The most common bony sarcomas include: chondrosarcoma, osteosarcoma, chordoma, Ewing's sarcoma. Given the relative rarity of each histologic diagnosis, especially in the skull base, there is limited published data to guide the management of patients with skull base sarcomas. An electronic search of the literature was performed to obtain key publications in the management of bony sarcomas of the skull base published within the last decade. This article is thus a review of the multi-disciplinary management principles of primary bony sarcomas of the skull base. Of note, there have been several recent advancements in the realm of skull base sarcoma management that have resulted in improved survival. These include advances in: imaging and diagnostic techniques, surgical techniques that incorporate oncologic surgical principles, conformal radiation paradigms and targeted systemic therapies. Early access to coordinated multi-disciplinary subspecialty care immediately at suspicion of diagnosis has further improved outcomes. There are several ongoing trials in the realms of radiation therapy and systemic therapy that will hopefully provide further insight about the optimal management of bony sarcomas of the skull base.

Temporal Galeofascial Flap for Reconstruction After Transmaxillary Approaches to the Clival Region

BACKGROUND

A paramount concern after transmaxillary approaches has been skull base reconstruction. Regional pedicled flaps represent the best reconstructive option. We have described a technique to harvest a lateral-based multilayered vascularized flap for skull base reconstruction after resection of large tumors using the transmaxillary transpterygoid approach (TMTPA).

METHODS

We performed a cadaver study using the TMTPA to harvest the combined temporal galeofascial flap (CTGF). The first layer, with major sealing capabilities, is composed by a temporoparietal galeal-pericranial flap. The second layer is composed by temporal muscle fascia to provide mechanical support for flap dural engrafting.

RESULTS

The CTGF provides excellent coverage of both the clival dural lining and the ipsilateral pterygopalatine fossa structures (×1.6). The CTGF is pliable and easy to harvest. It offers great flexibility in flap content and design, providing a large quantity of vascularized tissue. The vascular pedicle derives from the superficial temporal vessels, which can ensure flap trophism.

CONCLUSIONS

CTGF represents an effective option as a regional multilayered pedicled flap for skull base reconstruction after resection of clival tumors using the TMTPA. The flap pedicle, owing to its anatomical location, will often be preserved even after repeated microsurgical or endoscopic procedures, providing a technical alternative for reconstruction even in patients who have undergone multiple surgeries with low residual availability of regional flaps.

Temporal myofascial segmentation for multilayer reconstruction of middle cranial fossa floor after extradural subtemporal approach to the clival and paraclival region

BACKGROUND

Skull-base reconstruction represents a concern after resection of middle fossa (MF) tumors by the extradural subtemporal transzygomatic approach (ESTZ). Regional pedicled flaps appear to be the best option. This study describes a technique for temporal myofascial segmentation to harvest a multilayered vascularized flap for MF reconstruction, which might preserve temporal muscle (TM) function and its blood supply.

METHODS

The technique to harvest a combined segmented temporal myofascial flap (CSTMF) is described. The flap consists in a temporal fascial (TFF) and a muscle flap (TMF), composed by TM anterior-medial bundle (AMB).

RESULTS

CSTMF provides wide coverage of dural lining, through the TFF, and of dead-space, through the TMF. The possibility to tailor TMF according to the need, anatomically preserving the blood supply, enables to significantly increase its volume.

CONCLUSION

CSTMF represents an effective option as regional multilayered pedicled flap for MF reconstruction, potentially preserving TM function and minimizing the cosmetic impact.

Orbitocranial Approaches to the Skull Base

There are a myriad of approaches and surgical options for removal and treatment of skull base diseases. While, historically, large open approaches have been preferred, several endoscopic and minimally invasive techniques are now available that preserve intraoperative visualization and surgical success while minimizing morbidity and recovery times. Herein, the authors review common open, minimally invasive, and endoscopic approaches to the anterior skull base.

Free-Flap Reconstruction of Skull Base and Orbital Defects

Orbital and anterior skull base defects present a significant challenge for reconstruction due to the complexity of the anatomy and the need for separation of intracranial and extracranial contents in this area. While endoscopic techniques have revolutionized the treatment of many anterior skull base defects, microvascular free tissue transfer is a viable option for large volume defects not suitable for traditional open approaches or for cases where endoscopic techniques have failed. The various free tissue transfer techniques for anterior skull base and orbit, as well as the advantages and disadvantages, are reviewed.

Increased Defect Size is Associated with Increased Complication Rate after Free Tissue Transfer for Midanterior Skull-Base Reconstruction

Objective  Complications after skull-base reconstruction are often problematic. We consider that local factors, for example, localization of defect areas are possible risk factors. This study aimed to investigate our case series of skull-base reconstructions in our institution and to identify local risk factors that predispose to wound complications. Design  This study is presented as a retrospective study. Setting  Research work was took place at Nagoya University Hospital. Participants  Forty-eight patients who had undergone reconstruction after midanterior skull-base resection between January 2004 and December 2015 were included in this study. Defects apart from the skull-base were categorized into nasal and paranasal cavity (N), orbit (O), palate (P), and facial skin (S). Postoperative local complications including cerebrospinal fluid (CSF) leakage, local infection, wound dehiscence (fistula in face or palate), and flap necrosis (partial or total) were investigated. Main Outcome Measures  Main outcome measures were postoperative complications in patients with each defect. Results  Apart from the skull-base, defects included 28 ONP (58.3%), 10 ONPS (20.8%), 3 ON (6.3%), 3 ONS (6.3%), 1 NP (2.1%), and 1 OS (2.1%). Comparison based on numbers of resected regions revealed that a significantly higher complication rate was seen in patients with four resected regions than in those with three regions (90.0% vs. 45.2%, p  < 0.05). Conclusion  There was a trend suggesting that more resected regions corresponded to a greater risk of complications in midanterior skull-base reconstruction. Reconstructive surgeons need to carefully consider the reconstruction of such complicated defects.

Impact of Dural Resection on Sinonasal Malignancies with Skull Base Encroachment or Erosion

Objectives  (1) To determine the occult rate of dural invasion in patients with tumors extending to and/or eroding the bony anterior skull base but without evidence of dural invasion on preoperative imaging. (2) To determine the impact of dural resection and of skull base erosion on survival outcomes in this group of patients (without evidence of dural invasion upon preoperative imaging). Study Design  Retrospective study. Setting  Tertiary care academic center. Participants  Patients with sinonasal malignancies with anterior skull base encroachment/erosion without dural invasion on preoperative imaging treated surgically. Main Outcome Measures  (1) Histopathologic disease in the dura in patients who had dural resection and (2) Oncologic outcomes (5-year local recurrence, dural recurrence, disease-specific survival, and overall survival) in patients with and without dural resection, and patients with and without skull base erosion. Results  Thirty-seven patients were included. The occult rate of dural invasion was 54%. Patients with dural resection had improved margin control versus those without dural resection (90% vs 56%, p  = 0.02). Dural resection improved 5-year overall survival only in patients with esthesioneuroblastoma compared with bony skull base resection alone (100% vs 75%, p  = 0.03). Patients with skull base erosion had reduced local control versus those without erosion (63% vs 93%, p  = 0.047). Conclusion  This study suggests a substantial rate of occult dural invasion despite no overt imaging findings. Dural resection may be associated with improved margin control, but no oncologic benefit except for esthesioneuroblastomas, although treatment heterogeneity and small sample size may limit conclusions.

Skull Base Reconstruction in the Pediatric Patient

Introduction  Pediatric skull base and craniofacial reconstruction presents a unique challenge since the potential benefits of therapy must be balanced against the cumulative impact of multimodality treatment on craniofacial growth, donor-site morbidity, and the potential for serious psychosocial issues. Objectives  To suggest an algorithm for skull base reconstruction in children and adolescents after tumor resection. Materials and Methods  Comprehensive literature review and summary of our experience. Results  We advocate soft-tissue reconstruction as the primary technique, reserving bony flaps for definitive procedures in survivors who have reached skeletal maturity. Free soft-tissue transfer in microvascular technique is the mainstay for reconstruction of large, three-dimensional defects, involving more than one anatomic region of the skull base, as well as defects involving an irradiated field. However, to reduce total operative time, intraoperative blood loss, postoperative hospital stay, and donor-site morbidity, locoregional flaps are better be considered the flap of first choice for skull base reconstruction in children and adolescents, as long as the flap is large enough to cover the defect. Our "workhorse" for dural reconstruction is the double-layer fascia lata. Advances in endoscopic surgery, image guidance, alloplastic grafts, and biomaterials have increased the armamentarium for reconstruction of small and mid-sized defects. Conclusions  Skull base reconstruction using locoregional flaps or free flaps may be safely performed in pediatrics. Although the general principles of skull base reconstruction are applicable to nearly all patients, the unique demands of skull base surgery in pediatrics merit special attention. Multidisciplinary care in experienced centers is of utmost importance.

Open Anterior Skull Base Reconstruction: A Contemporary Review

Skull base extirpative and reconstructive surgery has undergone significant changes due to technological and operative advances. While endoscopic resection and reconstruction will continue to advance skull base surgery for the foreseeable future, traditional open surgical approaches and reconstructive techniques are still contemporarily employed as best practices in certain tumors or patient-specific anatomical cases. Skull base surgeons should strive to maintain a working knowledge and technical skill set to manage these challenging cases where endoscopic techniques have previously failed, are insufficient from anatomical constraints, or tumor biology with margin control supersedes the more minimally invasive approach. This review focuses on the reconstructive techniques available to the open skull base surgeon as an adjunct to the endoscopic reconstructive options. Anatomic considerations, factors relating to the defect or patient, reconstructive options of nonvascular grafts, local and regional flaps, and free tissue transfer are outlined using the literature and author's experience. Future directions in virtual surgical planning and emerging technologies will continue to enhance open and endoscopic skull base surgeon's preparation, performance, and outcomes in this continually developing interdisciplinary field.

Transfacial and Craniofacial Approaches for Resection of Sinonasal and Ventral Skull Base Malignancies

Malignancies of the paranasal sinuses and ventral skull base present unique challenges to physicians. A transfacial or craniofacial approach allows for wide, possibly en bloc, resection and is ideal for tumors that involve surrounding soft tissue, the palate, the orbit, anterolateral frontal sinus, and lateral dura. Transfacial approaches include a lateral rhinotomy often combined with a medial, subtotal, or total maxillectomy. Reconstruction is most commonly performed with a pericranial flap to separate the intranasal and intracranial compartments. These approaches have evolved and been refined but now are usually reserved for advanced tumors not amenable to endoscopic resection.

Complications of Open Approaches to the Skull Base in the Endoscopic Era

Objective It is important to characterize the developing complication profile of the open approach as it becomes reserved for more complex disease during the endoscopic era. Our objective was to characterize complication rates of current open skull base surgery. Design Retrospective chart review. Setting Tertiary care center. Participants The study group consisted of 103 patients and 117 open skull base surgeries were performed from 2008 to 2012. Main Outcome Measures Intraoperative/postoperative complications. Methods Fisher exact test and Wilcoxon rank sum test evaluated for associations of complications with potential risk factors. Results Postoperative complications occurred in 53 (45%) cases, of which 36 (31%) were major complications. Malignancy, dural grafting, age, and obesity were not associated with complications. Flap reconstruction was associated with increased complication rates (odds ratio = 2.27; 95% confidence interval: 1.03-5.04). Conclusion The open approach is increasingly utilized for only the most complex lesions, and selection bias cannot be overstated in comparative series. This study suggests that current open complication rates may be above those cited from prior studies, and patient and physician expectations should be adjusted accordingly.

Role of free tissue transfer in skull base reconstruction

Objective

Free tissue transfer to the skull base provides a watertight seal to prevent CSF leakage and donor tissue tailored to the individual defect.

Study Design and Setting

Retrospective chart review of 38 patients who underwent free tissue transfer to the skull base between November 1995 and October 2005 at an academic, tertiary referral center.

Results

There were 23 male and 15 female patients (average age, 58.1 years) with skull base defects resulting from oncologic resection or head trauma most frequently. Donor sites included the radial forearm (25), rectus abdominis (12), latissimus dorsi (4), anterolateral thigh, scapula, serratus anterior, and ulna (1 each). Seven patients required a second free tissue transfer indicated for flap death (3), partial flap necrosis (2), pneumocephalus (1), or tumor recurrence (1). Two patients died in the immediate postoperative period.

Conclusions

Free tissue transfer is a robust option in the repair of post-surgical and post-traumatic skull base defects. © 2007 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

Unfavourable results in skull base surgery

Treatment of skull base tumors involves multiple specialities. The lesions are usually advanced and the treatment is often associated with unfavorable results, which may be functional and/or aesthetic. Here we have done an analysis for the complications and unfavorable results of 546 cases treated surgically by a single craniofacial surgeon over a period of 14 years. The major morbidity ranges from death to permanent impairment of vital organ functions (brain, eye, nose), infections, tissue losses, flap failures, treatment associated complications, psychosocial issues, and aesthesis besides others. This article is aimed at bringing forth these unfavorable results and how to avoid them.

Delayed complications after anterior craniofacial resection of malignant skull base tumors

Objective To report complications occurring at least 6 months after completion of treatment for patients with anterior skull base malignancy undergoing anterior craniofacial resection (CFR). Design Retrospective review of medical records of all patients undergoing traditional CFR for treatment of anterior skull base malignancy from 2002 through 2011. Setting Massachusetts General Hospital/Massachusetts Eye and Ear Infirmary Cranial Base Center. Participants Thirty-one consecutive patients who had at least 18 months of follow-up for analysis were reviewed. All patients underwent traditional CFR. A total of 28 patients received postoperative proton beam radiation therapy. Eleven patients received adjuvant chemotherapy. Main Outcome Measures A delayed complication was any complication occurring at least 6 months after the completion of treatment. Results Seventeen patients had delayed complications. Orbital complications were the most common type (13 patients) followed by issues with wound healing (6 patients). The most common orbital complication was epiphora (7 patients). The most common wound complication was a nasocutaneous fistula (5 patients). Conclusions Patients with anterior skull malignancy can develop complications months to years after the completion of treatment. Therefore, it is important to continue to follow and report complications for several years when deciding on the optimal approach for treatment of these patients.

Skull invaders: when surgical pathology and neuropathology worlds collide

Skull and dura serve as effective barriers to penetration by most tumors, often preventing masses originating intracranially from extending into the contiguous bone and soft tissues, or those arising in head and neck regions from extending into the dura and brain tissue. We review our 15-year experience with extracranial tumors that had sufficiently invaded adjacent skull, dura, or brain from the "outside-in" to require a neurosurgeon to participate in the surgical resection and discuss our 40 cases in context with the literature. Sinonasal-origin tumors (n = 17) and cutaneous tumors (n = 10) were the most frequent skull-invaders. Most of the cutaneous tumor types were squamous cellcarcinomas (n = 9); diverse sinonasal-origin types included 4 squamous cell carcinomas, 4 adenoid cystic carcinomas, 2 sinonasal undifferentiated carcinomas, 2 sinonasal adenocarcinomas, and single examples each of sinonasal-origin hemangiopericytoma, solitary fibrous tumor, melanoma, mucocele, and teratocarcinoma. There were 9olfactory neuroblastomas, and middle ear-origin basal cell carcinoma,recurrent glomus jugulare, and orbital malignant hidradenoma were also seen. Unique tumors included a cutaneous cylindroma invasive of skull convexity occurring in familial cylindromatosis and a ganglioneuroma of the middle ear with massive bilateral skull base extension. Convexity dural spread, a seldom-reported pattern of dissemination, was seen in 1 olfactory neuroblastoma and 1 adenoid cystic carcinoma. The ability to show skull/dural invasion did not correlate with specific histopathologic features; even benign tumor types can show skull/dural penetration.

Outcomes following Microvascular Free Tissue Transfer in Reconstructing Skull Base Defects

Objective Successful resection of complex tumors involving the skull base (SB) depends on the ability to reconstruct the resulting defects. The objective of this study was to assess the outcomes of patients undergoing reconstruction after resection of SB tumors with free flaps. Methods From 1995 to 2010 a retrospective review of cases was undertaken. Demographics, histology, surgical management, complications, locoregional control, and survival were analyzed. Results We performed 62 flaps in 57 patients. There was a preponderance of sinonasal malignancies (45%), and most lesions involved the anterior SB (81%). A total of 94% of patients underwent radiotherapy. Reconstruction was undertaken mainly with anterolateral thigh (37%) or radial forearm (34%) flaps. Complications occurred in 17% of patients, and the flap's success rate was 94%. Conclusion Free flaps are versatile and highly reliable for reconstructing defects resulting from resections of the SB. They should be considered for SB reconstruction of large three-dimensional defects as well as defects involving an irradiated field. Successful reconstruction of the SB can be performed using a small number of highly dependable flaps.

A new concept for classifying skull base defects for reconstructive surgery

To classify the defects of the skull base, we present a new concept that is intuitive, simple to use, and consistent with subsequent reconstructive procedures. The centers of defects are determined in the anterior (I) or middle (II) skull base. The defects are classified as localized in the defect's center (Ia, IIa) or extended horizontally (Ib, IIb) or vertically (Ic, IIc) from the defect's center. Accompanying defects of the orbital contents and skin are indicated by "O" and "S," respectively. An algorithm for selecting subsequent reconstructive procedures was based on the classification. Using the new system, we retrospectively reclassified 90 skull base defects and examined how the defect classifications were related to the reconstructive flaps used and postoperative complications. All defects were reclassified with the new system without difficulty or omission. The mean correlation rate was high (88%) between the flaps indicated by the new classification and the flaps that had actually been used. The rate of postoperative complications tended to be higher with Ia, Ic, and IIb defects and combined defects. Our new classification concept can be used to classify defects and to help select flaps used for subsequent reconstructive procedures.

Review of skull base reconstruction using locoregional flaps and free flaps in children and adolescents

Tumors of the skull base are rare in children, and reconstruction in such patients has rarely been reported. We reviewed 16 cases of skull base reconstruction in patients under 18 years. The study group consisted of 10 boys and 6 girls, whose ages ranged from 2 to 17 years. Of the 16 cases, eight tumors were benign and eight were malignant. Defects were anterior in six cases, lateral in eight cases, and anterolateral in two cases. Reconstruction was performed with locoregional flaps in 11 cases and with free flaps in 5 cases. No significant difference was found between locoregional flaps and free flaps in total operative time, intraoperative blood loss, or postoperative hospital stay. However, in some cases, total operative time, reconstruction time, and blood loss increased to a degree unacceptable for pediatrics. Minor complications occurred in three patients and a major complication occurred in one case. Of four patients, three patients with postoperative complications had undergone chemoradiotherapy. Because of the physical weakness of pediatric patients, complicated reconstructive procedure should be avoided. We believe locoregional flaps will become the first choice for reconstruction. However, if patients have large, complex defects and have received radiotherapy, appropriate free flaps should be used to avoid postoperative complications.

Reconstruction techniques in skull base surgery

One of the major challenges of cranial base surgery is reconstruction of basal dural defects. Ineffective reconstruction may result in potentially life-threatening complications such as cerebrospinal fluid leak, meningitis, and tension pneumocephalus. Goals of reconstructive procedures are to repair the dural defect and to separate intracranial contents from bacteria-laden secretion of the mouth, nose, and sinus. Different reconstructive techniques have been reported. Multiple factors may influence the surgical choice of reconstructive technique and its outcome. Regional pedicled flap and vascular free flaps represent the best reconstructive options because vascularized tissues promote fast and complete healing. A variety of endoscopic pedicled mucosal flaps within the nasal cavity have also been described. The different reconstruction techniques are described and discussed in terms of indications, advantages, and drawbacks.

Reliability of and indications for pericranial flaps in anterior skull base reconstruction

Owing to changes in the treatment of skull-base tumors, such as perioperative radiotherapy and advances in approaching the skull base, the use of pericranial flaps should be reconsidered. Therefore, we reviewed the reliability of and indications for pericranial flaps in 26 cases in terms of patient background, the effects of preoperative and postoperative treatment, and the pattern of blood circulation. Flaps were harvested as 25 anteriorly based and 4 laterally based. As a result, postoperative complications were observed in 4 patients. No other risk factors, except for heavy smoking, were observed relative to patient background. Sixteen patients had perioperative radiotherapy, and complication rate was significantly higher in patients with preoperative radiotherapy than patients without preoperative radiotherapy (P=0.014). However, no complications, such as cerebral spinal fluid leakage and intracranial infection, were observed in patients receiving postoperative radiotherapy. Laterally based pericranial flaps had a high complication rate (25%), but it was not significantly higher than anteriorly based flaps (P=0.467). Five anteriorly based flaps were harvested with less feeding vessels as usual because of applying dismasking flap approach, but it did not lead to increasing in complication rate. We conclude that a pericranial flap can be used for skull base reconstruction even if postoperative radiotherapy is planned but might be avoided for patients who have received preoperative radiotherapy. In addition, particular care and flap design should be taken to preserve sufficient vascularity when pericranial flaps are raised as laterally based and less feeding vessels as usual.