Malignant Skull Base Tumors Research Articles

Free temporalis muscle fascia graft in dural reconstruction following surgical resection of intermediate and malignant skull base tumors: A 10-year experience from a single center.

Data from patients with post-ablative dural defects reconstructed using a free temporalis muscle fascia graft (FTFG) after resection of anterior or central skull base tumors were retrospectively analyzed. The primary predictor and outcome variables were the reconstructive methods for dural repair and postoperative cerebrospinal fluid (CSF) leakage rate, respectively. Eighty patients were included, and 94 postoperative dural reconstructions were performed using FTFG. The postoperative CSF leakage rate was 3.19%. The postoperative CSF leakage rates did not significantly differ between open and endonasal endoscopic surgeries (1.92% vs. 4.88%; p > 0.05). In cases completed using the endonasal endoscopic approach, the postoperative CSF leakage rate was significantly associated with the intraoperative CSF leak flow (p < 0.05). Post-ablative dural defect reconstruction using FTFG resulted in low postoperative CSF leakage and complication rates comparable to those of free fascia lata graft from available literature.

Reconstruction of midface defects after surgical treatment of skull base tumors

Aim. To perform a retrospective analysis of the results of surgical treatment of patients with anatomically widespread malignant skull base tumors and evaluate the possibility of using various types of closure of skull base defects. Materials and methods. The study is based on a retrospective analysis of medical records of 139 patients with midface tumors aged 14 to 77 years, operated from 1995 to 2023. Histological structure of the tumors was different. we divided all methods of reconstruction of midface defects into two groups. In the group 1, plastic closure of the defect was per-formed using flaps from anatomical areas located close to the defect. In the group 2, reconstruction was performed using flaps from distant anatomical areas. Results. In the postoperative period, we did not observe gross cicatricial face deformities, impaired chewing and swallowing functions due to cicatricial contractures of chewing muscles. Titanium mesh for reconstruction was used in 68 (48.9 %) cases. The osteoperiosteal aponeurotic flap was used in 5 cases, of which in 3 (3.8 % of the total number of patients of the 1st group) – in combination with the temporal muscle. The thoracodorsal flap was used in 62 (44.6 %) patients. various methods of its movement and combination with the anterior dentate muscle were used. In 41 (66.1 %) cases, good cosmetic and functional results were obtained. These indicators correlated with adequate choice of reconstruction method allowing elimination of most of the impaired functions. Conclusion. The use of the presented technologies for plastic closure of post-resection defects of various parts of the skull base, including those combined with extensive damage to the midface, leads to leveling of the cosmetic and functional consequences of surgical aggression.

Geographic Disparities in the Proliferation of Minimally Invasive Approaches for Sellar/Parasellar Lesions

The aim of this study was to understand the global trends in the proliferation of various minimal invasive approaches including the endonasal endoscopic approach (EEA) and the extended EEA. Questions about the use of the supraorbital and transorbital approach were also included. We conducted an online anonymized and validated survey using a structured questionnaire on the use of EEA and EEEA, as well as periorbital approaches, in the management of sellar, suprasellar, and parasellar lesions in different parts of the world. A total of 261 responses were received. Of respondents, 195 (74.71%) received training in EEA, but less than half during residency. Of respondents, 108 mentioned that parasellar lesions comprised 5%-25% of the total cases encountered in the past 5 years in their practice. Only half of the respondents relied on ENT (ear, nose, and throat) colleagues for the approach. Whereas Europe and South America relied on EEA about half the time, North America and Asia used EEA only a third of the time; in Africa, EEA was hardly used at all. The proportion of respondents using EEA for >50% of giant pituitary adenoma, olfactory groove meningiomas, craniopharyngiomas, chordoma, tuberculum sella meningiomas, and malignant skull base tumors was 34.5%, 3.4%, 13%, 16%, 7%, and 10%, respectively. EEEA, the supraorbital approach, and the transorbital approach were used by 50.6%, 54.4%, and 34.5%, respectively. EEEA was used predominantly by those having an experience of 11-20 years or >30 years after residency (P= 0.018) and those from North America (64.1%). Our survey highlights the various geographic and demographic trends in the use of the EEA for sellar, suprasellar, and parasellar diseases. Although EEA training was present in almost all countries, the approach was not used as frequently as would have been expected for giant adenomas, craniopharyngiomas, and chordomas. After 20 years of education about the technique and indications of the endoscopic endonasal approach, through countless courses and publications, the use of EEA is still lagging, particularly in developing countries.

Predictors of surgical complications in surger y of disseminated skull base tumors

Post-surgical complications are rather important, and, perhaps, more significant factors determining the efficiency of the provided treatment together with the natural oncological disease course, accompanying pathology, and peculiarities of the adjuvant therapy. The decrease in the frequency and severity of these complications, revealing of modifiable and non-modifiable risk factors, their prevention and reduction are definitely of scientific and practical interest. The aim of the work is the search for predictors of post-surgical complications in the patients with disseminated malignant skull base tumors. The retro-prospective single-center cohort study based on the analysis of the results of surgical treatment of 161 patients with such neoplasms was carried out. The study covered the patients at the age of 19–84 years, with the average age of 55 years (statistical deviation: +\- 1.2). There were 78 women and 83 men. Accordingly, the sex distribution was 1:1.064. The pre-surgical radical radiotherapy was made for 43 patients (26.71 %); 21 patients (13.04 %) underwent one or several cycles of multiagent chemotherapy. Morphologically, there were 16 different types of tumors, among which the epithelial tumors 40.37 % (n=65) prevailed: epidermoid cancer — 16.15 % (n=26), sinonasal cancer — 8.07 % (n=13), and acinic cell carcinoma 5.59 % (n=9). Sarcomas were diagnosed in 12 patients (7.45 %). The study results demonstrate the lack of particular statistically substantiated symptoms or clinical factors — predictors, individually and independently affecting the unfavorable results of the surgical treatment of the patients with disseminated malignant skull base tumors. On the contrary, the syndromological combination of local, general and organizational problems definitely influences the surgery result significantly, while not all mathematically predicted combinations can be formalized into some clinical equivalent.

Extent of Resection Research in Skull Base Neurosurgery: Previous Studies and Future Directions

Surgery is the first-line therapy for most benign and malignant skull base tumors. Extent of resection (EOR) is a metric commonly used for preoperative surgical planning and to predict risk of postoperative tumor recurrence. Therefore, understanding the evidence on EOR in skull base neurosurgery is essential to providing optimal care for each patient. Several studies from the skull base neurosurgery literature have presented investigations of various topics related to EOR, including 1) preoperative EOR scoring systems, 2) intraoperative EOR scoring systems, 3) EOR and tumor recurrence, and 4) EOR and functional outcomes. We propose that future investigations should focus on the following elements to improve EOR research in skull base neurosurgery: 1) multi-institutional collaboratives with treatment propensity matching; 2) expert consensus and mixed-methods study design; and 3) predictive analytics/machine learning. We believe that these methods offer several advantages that have been described in the literature and that they address limitations of previous studies. The aim of this review was to inform future study design and improve the overall quality of subsequent investigations on EOR in skull base neurosurgery.

Early and late complications after open and endoscopic neurosurgery for complex skull base and craniofacial pathology: Case series, illustrative cases, and review

Advances in open and endoscopic surgical approaches to the skull base have improved access of patients with formidable skull base and craniofacial pathology to surgical options but carry risks of early and late complications. MethodsWe identified complications in a retrospective case series of open and endoscopic complex skull base and craniofacial surgery (N = 60) with comparison to our institutional database for craniotomy (N = 2143). A literature review was completed. ResultsAcute complications occurred in 38% of patients, and delayed complications occurred in 17%. Compared to our institutional craniotomy database (n = 2143), complex skull base surgery had higher rates for: any major complication (17% vs 37%); motor deficit (1.7% vs 6.7%); encephalopathy (1.4% vs 6.7%); diabetes insipidus (1.3% vs 8.3%); unplanned OR take back (1.2% vs 38%); symptomatic intracranial bleeding (0.8% vs 15%); CSF leak (0.7% vs 13.3%); deep venous thrombosis (0.4 vs 3.3%); ventilator-associated pneumonia (0.2% vs 3.3%); pulmonary embolus (0.2% vs 1.6%); and pneumocephaly (0.1% vs 3.3%). Thirteen case vignettes highlight: flap-related complications; pseudoaneurysms; CNS vasospasm; sinus thrombosis; osteoradionecrosis-related dural leaks; tension pneumocephalus; low pressure hydrocephalus; airway compromise; hemoptysis; Takotsubo cardiomyopathy; and adrenal crisis. Our literature review identified a wide spectrum of complications (N = 65). ConclusionThrough advances in multimodal treatment with surgery, chemotherapy, and radiation treatment for malignant skull base tumors, survival rates have improved. These survivors remain at risk for both early and delayed complications.

Rapid Automated Analysis of Skull Base Tumor Specimens Using Intraoperative Optical Imaging and Artificial Intelligence.

Accurate specimen analysis of skull base tumors is essential for providing personalized surgical treatment strategies. Intraoperative specimen interpretation can be challenging because of the wide range of skull base pathologies and lack of intraoperative pathology resources. To develop an independent and parallel intraoperative workflow that can provide rapid and accurate skull base tumor specimen analysis using label-free optical imaging and artificial intelligence. We used a fiber laser-based, label-free, nonconsumptive, high-resolution microscopy method (<60 seconds per 1 × 1 mm2), called stimulated Raman histology (SRH), to image a consecutive, multicenter cohort of patients with skull base tumor. SRH images were then used to train a convolutional neural network model using 3 representation learning strategies: cross-entropy, self-supervised contrastive learning, and supervised contrastive learning. Our trained convolutional neural network models were tested on a held-out, multicenter SRH data set. SRH was able to image the diagnostic features of both benign and malignant skull base tumors. Of the 3 representation learning strategies, supervised contrastive learning most effectively learned the distinctive and diagnostic SRH image features for each of the skull base tumor types. In our multicenter testing set, cross-entropy achieved an overall diagnostic accuracy of 91.5%, self-supervised contrastive learning 83.9%, and supervised contrastive learning 96.6%. Our trained model was able to segment tumor-normal margins and detect regions of microscopic tumor infiltration in meningioma SRH images. SRH with trained artificial intelligence models can provide rapid and accurate intraoperative analysis of skull base tumor specimens to inform surgical decision-making.

Facial nerve management in patients with malignant skull base tumors.

The course of the facial nerve through the cerebellopontine angle, temporal bone, and parotid gland puts the nerve at risk in cases of malignancy. In contrast to Bell's palsy, which presents with acute facial paralysis, malignancies cause gradual or fluctuating weakness. We review malignancies affecting the facial nerve, including those involving the temporal bone, parotid gland, and cerebellopontine angle, in addition to metastatic disease. Intraoperative management of the facial nerve and long term management of facial palsy are reviewed. Intraoperative management of the facial nerve in cases of skull base malignancy may involve extensive exposure, mobilization, or rerouting of the nerve. In cases of nerve sacrifice, primary neurorrhaphy or interposition grafting may be used. Cranial nerve substitution, gracilis free functional muscle transfer, and orthodromic temporalis tendon transfer are management options for long term facial paralysis. Temporal bone, parotid gland, and cerebellopontine angle malignancies pose a tremendous risk to the facial nerve. When possible, the facial nerve is preserved. If the facial nerve is sacrificed, static and dynamic reanimation strategies are used to enhance facial function.

The Role of Advanced Endoscopic Resection of Diverse Skull Base Malignancies: Technological Analysis during an 8-Year Single Institutional Experience.

Background Resection of skull base malignancies poses complex pathological and treatment-related morbidities. Recent technological advancements of endoscopic endonasal surgery (EES) offer the ability to reexamine traditional treatment paradigms with endoscopic procedures. The utility of EES was quantitatively examined in a longitudinal series with attention to morbidities and postoperative outcomes. Methods A single-center retrospective review was performed of all malignant sinonasal tumors from 2010 to 2018. Patients with purely EES were selected for analysis. Disease features, resection extent, complications, adjuvant treatment, recurrence, and survivability were assessed. Despite the mixed pathological cohort, analysis was performed to identify technical aspects of resection. Results A total of 68 patients (47.6% males and 52.4% females, average age: 60.3 years) were included. A diversity of histotypes included clival chordoma (22.1%), olfactory neuroblastoma (14.7%), squamous cell carcinoma (11.8%), and adenoid cystic carcinoma (11.8%). Gross total resection (GTR) was achieved in 83.8% of cases. Infection (4.4%) and cerebrospinal fluid leak (1.5%) were the most common postoperative complications. Total 46 patients (67.6%) underwent adjuvant treatment. The average time between surgery and initiation of adjunctive surgery was 55.7 days. Conclusion In our 8-year experience, we found that entirely endoscopic resection of mixed pathology of malignant skull base tumors is oncologically feasible and can be accomplished with high GTR rates. There may be a role for EES to reduce operative morbidity and attenuate time in between surgery and adjuvant treatment, which can be augmented through recent mixed reality platforms. Future studies are required to systematically compare the outcomes with those of open surgical approaches.

Stereotactic Radiosurgery and Stereotactic Radiotherapy for Malignant Skull Base Tumors.

The role of stereotactic radiosurgery/stereotactic radiotherapy (SRS/SRT) for malignant skull base tumors was summarized and discussed. The treatment of skull base tumors remains challenging. Their total resection is often difficult. SRS/SRT is one useful treatment option for residual or recurrent tumors after surgical resection in cases of primary skull base tumors. If skull base metastasis and skull base invasion are relatively localized, they can be candidates for SRS/SRT. Low rates of cervical lymph node involvement in early-stage (N0M0, no lymph node involvement or distant metastasis) nasal and paranasal carcinomas (NpNCa) and external auditory canal carcinomas (EACCa) have been reported in the literature. Such cases might be good candidates for SRS/SRT as the initial therapy. We previously reported the results of SRS/SRT for various malignant extra-axial skull base tumors. In addition, treatment results of early-stage head and neck carcinomas were summarized. Those of our data and those of other reported series were reviewed here to clarify the usefulness of SRS/SRT for malignant extra-axial skull base tumors.

Malignant tumors of the skull base

Malignant skull base tumors consist of aheterogeneous group of malignancies that can be divided into primary and secondary (metastatic) skull base tumors. In addition, according their anatomical location, they can be further divided into tumors of the anterior, middle, or posterior cranial fossa. Although malignant skull base tumors do not rigorously respect anatomical borders, their anatomical occurrence can potentially be helpful for possible differential diagnosis. This article is focused on the most common malignant tumors of the skull base and their imaging and clinical presentations.

Prospective Evaluation of Health-Related Quality of Life in Patients Undergoing Anterolateral Craniofacial Resection with Orbital Exenteration.

Objective This study was aimed to evaluate health-related quality of life in patients undergoing anterolateral craniofacial resection (AL-CFR) with orbital exenteration (OE) for malignant skull base tumors and to investigate the effects of early psychiatric intervention. Design Present study is a prospective, observational study. Setting The study took place at the hospital department. Participants Twenty-six consecutive patients were selected who underwent AL-CFR with OE at our hospital between 2005 and 2015. Main Outcome Measures Health-related quality of life was assessed preoperatively and 3, 6, 12, and 24 months after surgery using the Hospital Anxiety and Depression Scale (HADS) and medical outcomes study 8-items Short Form health survey (SF-8). In all cases, psychiatric intervention was organized by the consultation liaison psychiatry team preoperatively and postoperatively. Results Ten (38.0%) of the 26 patients died and 16 (62.0%) were alive and disease-free at the end of the study. The 3-year overall and disease-free survival rates were 64.9% and 53.3%, respectively. Twenty-one patients (80.8%) developed psychiatric complications after surgery and needed treatment with psychotropic medication. Before surgery, 28% of patients had HADS scores ≥8 for anxiety and 20% had scores ≥8 for depression. Seven of the eight items in the SF-8 were significantly lower than those for the general Japanese population. However, scores for all the SF-8 items gradually improved during postoperative follow-up, reaching approximately 50 points, which is the national standard value, at 2 years after surgery. Conclusions Craniofacial resection with OE was feasible and well tolerated in patients with malignant skull base tumors who received early psychiatric intervention to decrease the considerable psychological impact of this procedure.

Stereotactic radiosurgery for trigeminal pain secondary to recurrent malignant skull base tumors.

The objective of this study was to assess outcomes after Gamma Knife radiosurgery (GKRS) re-irradiation for palliation of patients with trigeminal pain secondary to recurrent malignant skull base tumors. From 2009 to 2016, 26 patients who had previously undergone radiation treatment to the head and neck received GKRS for palliation of trigeminal neuropathic pain secondary to recurrence of malignant skull base tumors. Twenty-two patients received single-fraction GKRS to a median dose of 17 Gy (range 15-20 Gy) prescribed to the 50% isodose line (range 43%-55%). Four patients received fractionated Gamma Knife Extend therapy to a median dose of 24 Gy in 3 fractions (range 21-27 Gy) prescribed to the 50% isodose line (range 45%-50%). Those with at least a 3-month follow-up were assessed for symptom palliation. Self-reported pain was evaluated by the numeric rating scale (NRS) and MD Anderson Symptom Inventory-Head and Neck (MDASI-HN) pain score. Frequency of as-needed (PRN) analgesic use and opioid requirement were also assessed. Baseline opioid dose was reported as a fentanyl-equivalent dose (FED) and PRN for breakthrough pain use as oral morphine-equivalent dose (OMED). The chi-square and Student t-tests were used to determine differences before and after GKRS. Seven patients (29%) were excluded due to local disease progression. Two experienced progression at the first follow-up, and 5 had local recurrence from disease outside the GKRS volume. Nineteen patients were assessed for symptom palliation with a median follow-up duration of 10.4 months (range 3.0-34.4 months). At 3 months after GKRS, the NRS scores (n = 19) decreased from 4.65 ± 3.45 to 1.47 ± 2.11 (p < 0.001); MDASI-HN pain scores (n = 13) decreased from 5.02 ± 1.68 to 2.02 ± 1.54 (p < 0.01); scheduled FED (n = 19) decreased from 62.4 ± 102.1 to 27.9 ± 45.5 mcg/hr (p < 0.01); PRN OMED (n = 19) decreased from 43.9 ± 77.5 to 10.9 ± 20.8 mg/day (p = 0.02); and frequency of any PRN analgesic use (n = 19) decreased from 0.49 ± 0.55 to 1.33 ± 0.90 per day (p = 0.08). At 6 months after GKRS, 9 (56%) of 16 patients reported being pain free (NRS score 0), with 6 (67%) of the 9 being both pain free and not requiring analgesic medications. One patient treated early in our experience developed a temporary increase in trigeminal pain 3-4 days after GKRS requiring hospitalization. All subsequently treated patients were given a single dose of intravenous steroids immediately after GKRS followed by a 2-3-week oral steroid taper. No further cases of increased or new pain after treatment were observed after this intervention. GKRS for palliation of trigeminal pain secondary to recurrent malignant skull base tumors demonstrated a significant decrease in patient-reported pain and opioid requirement. Additional patients and a longer follow-up duration are needed to assess durability of symptom relief and local control.

Single- and Multi-Fraction Stereotactic Radiosurgery Dose Tolerances of the Optic Pathways

Dosimetric and clinical predictors of radiation-induced optic nerve/chiasm neuropathy (RION) after single-fraction stereotactic radiosurgery (SRS) or hypofractionated (2-5 fractions) radiosurgery (fSRS) were analyzed from pooled data that were extracted from published reports (PubMed indexed from 1990 to June 2015). This study was undertaken as part of the American Association of Physicists in Medicine Working Group on Stereotactic Body Radiotherapy, investigating normal tissue complication probability (NTCP) after hypofractionated radiation. Eligible studies described dose delivered to optic nerve/chiasm and provided crude or actuarial toxicity risks, with visual endpoints (ie, loss of visual acuity, alterations in visual fields, and/or blindness/complete vision loss). Studies of patients with optic nerve sheath tumors, optic nerve gliomas, or ocular/uveal melanoma were excluded to obviate direct tumor effects on visual outcomes, as were studies not specifying causes of vision loss (ie, tumor progression vs RION). Thirty-four studies (1578 patients) were analyzed. Histologies included pituitary adenoma, cavernous sinus meningioma, craniopharyngioma, and malignant skull base tumors. Prior resection (76% of patients) did not correlate with RION risk (P=.66). Prior irradiation (6% of patients) was associated with a crude 10-fold increased RION risk versus no prior radiation therapy. In patients with no prior radiation therapy receiving SRS/fSRS in 1-5 fractions, optic apparatus maximum point doses resulting in <1% RION risks include 12 Gy in 1 fraction (which is greater than our recommendation of 10 Gy in 1 fraction), 20 Gy in 3 fractions, and 25Gy in 5 fractions. Omitting multi-fraction data (and thereby eliminating uncertainties associated with dose conversions), a single-fraction dose of 10Gy was associated with a 1% RION risk. Insufficient details precluded modeling of NTCP risks after prior radiation therapy. Optic apparatus NTCP and tolerance doses after single- and multi-fraction stereotactic radiosurgery are presented. Additional standardized dosimetric and toxicity reporting is needed to facilitate future pooled analyses and better define RION NTCP after SRS/fSRS.

Epidemiology, diagnosis, clinical symptoms, and classification of malignant primary skull base tumors

A review of literature presents up-to-date information on the prevalence, incidence, clinical manifestations, diagnosis, and classification of malignant primary skull base tumors (MPSBTs). In the structure of total cancer incidence, malignant head and neck tumors account for 5% of all annual cancer deaths in the USA and are among the 5 most common groups of tumors in males worldwide. These tumors develop most often in the sixth decade of life, occurring 2 times more often in males than in females. In Russia, the MPSBT incidence (as of 2012) was 0.62% out of all newly diagnosed malignant tumors. The incidence rate amounts to 0.66 per 100 000 population and is significantly higher than the global rate (0.44 per 100 000). About half of all malignant skull base tumors have the epithelial nature and affect the anterior parts of the skull base. The most frequent histological types of malignant skull base tumors are squamous cell carcinoma, adenocarcinoma, and non-Hodgkin's B cell lymphoma. Treatment of skull base tumors is an interdisciplinary problem and the area of interest of otolaryngologists, dentists, ophthalmologists, neurosurgeons, plastic surgeons, radiologists, and chemotherapists. Physical and endoscopic examinations, endoscopic transnasal biopsy, CT, MRI, PET/CT, and ultrasound are typically used for verification of the diagnosis, tumor staging, and selection of the treatment approach. The review describes the criteria for TNM staging of malignant tumors of the nasal cavity and paranasal sinuses in accordance with the 7th version of the TNM recommendations of the American Joint Committee on Cancer (AJCC). The TNM-based staging depends on the location (maxillary sinus, nasal cavity, or ethmoid labyrinth) and histological structure of the tumor, which, in turn, determines the tactics of comprehensive treatment and a prognosis group.

Craniofacial Resection for T4 Maxillary Sinus Carcinoma: Managing Cases with Involvement of the Skull Base.

The objective of this study was to clarify the outcomes of craniofacial resection for locally advanced maxillary sinus carcinoma classified as T4 and to present methods for managing cases involving the skull base. Case series with chart review. Tertiary university hospital. We performed anterolateral craniofacial resection in en bloc fashion for locally advanced maxillary sinus carcinoma at stage T4. Participants comprised 40 patients with T4 maxillary sinus carcinoma treated between 1992 and 2011. Surgical outcomes were analyzed retrospectively. Forty patients with stage T4a (n = 26) or stage T4b (n = 14) were included in this study. Five-year overall and disease-free survival rates for the 40 patients with T4 maxillary sinus carcinoma were 62.7% and 52.6%, respectively. Cavernous sinus involvement correlated significantly with worse prognosis (P = .012). In 35 cases without cavernous sinus involvement, previous treatment (P = .017) and positive margins (P = .019) correlated significantly with worse prognosis, and 5-year overall and disease-free survival rates were 72.4% and 55.3%, respectively. This study only included cases of locally advanced maxillary sinus carcinoma classified as T4. Considering the advanced stage, our study suggests relatively favorable outcomes and the importance of managing the cavernous sinus in en bloc resections of malignant skull base tumors. Craniofacial resection in en bloc fashion achieved good survival rates.

Impact of Chemoradiotherapy on CSF Leak Repair after Skull Base Surgery.

Background Transnasal endoscopic resection (TER) has become the treatment of choice for many skull base tumors. A major limitation of TER is the management of large dural defects and the need for repair of cerebrospinal fluid (CSF) leaks, particularly among patients who are treated with chemotherapy (CTX) or radiotherapy (RT). The objective of this study is to determine the impact of CTX and RT on the success of CSF leak repair after TER. Methods We performed a retrospective chart review of a single-institution experience of TER from 1992 to 2011. Results We identified 28 patients who had endoscopic CSF leak repair after resection of malignant skull base tumors. Preoperative RT was utilized in 18 patients, and 9 had undergone CTX. All patients required CSF leak repair with rotational flaps after cribriform and/or dural resection. CSF leak repair failed in three patients (11%). A history of RT or CTX was not associated with failed CSF leak repair. Conclusion Adjuvant or neoadjuvant CTX or RT is not associated with failed CSF leak repair. Successful CSF leak repair can be performed in patients with malignant skull base tumors with an acceptable risk profile.

Cyberknife Stereotactic Radiosurgery for Intracranial Chordomas

Introduction: Intracranial chordomas are rare malignant skull base tumors representing less than 1% of all intracranial neoplasms. Chordomas are locally aggressive with high recurrence rates regardless of the treatment. As a more convenient alternative to 8 weeks of standard post-operative fractionated radiotherapy we present the Stanford experience with skull base chordomas treated with CyberKnife (CK) stereotactic radiosurgery (SRS).

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.

Formation and Rupture of the Internal Carotid Artery Aneurysm after Multiple Courses of Intensity-Modulated Radiation Therapy for Management of the Skull Base Ewing Sarcoma/PNET: Case Report

Background Aneurysm formation after stereotactic irradiation of skull base tumors is rare. The formation and rupture of an internal carotid artery (ICA) aneurysm in a patient with skull base Ewing sarcoma/primitive neuroectodermal tumor (PNET), who underwent surgery followed by multiple courses of intensity-modulated radiation therapy (IMRT) and chemotherapy, is described. Case Description A 25-year-old man presented with a sinonasal tumor with intraorbital and intracranial growth. At that time cerebral angiography did not reveal any vascular abnormalities. The lesion was resected subtotally. Histopathologic diagnosis was Ewing sarcoma/PNET. The patient underwent multiple courses of chemotherapy and three courses of IMRT at 3, 28, and 42 months after initial surgery. The total biologically effective dose delivered to the right ICA was 220.2 Gy. Seven months after the third IMRT, the patient experienced profound nasal bleeding that resulted in hypovolemic shock. Angiography revealed a ruptured right C4–C5 aneurysm and irregular stenotic changes of the ICA. Lifesaving endovascular trapping of the right ICA was done. The patient recovered well after surgery but died due to tumor recurrence 6 months later. Conclusion Excessive irradiation of the ICA may occasionally result in aneurysm formation, which should be borne in mind during stereotactic irradiation of malignant skull base tumors.