The role of a virtual telephone clinic in the follow-up management of lateral skull base tumours.

OBJECTIVE: The purpose of this article was to determine the impact of employing a telephone clinic for follow-up of patients with stable lateral skull-base tumours. METHOD: An analysis of 1515 patients in the national lateral skull-base service was performed, and 148 patients enrolled in the telephone clinic to date were identified. The length of time that patients waited for results of their follow-up scans and the travel distance saved by patients not having to attend the hospital for their results was determined. RESULTS: The mean time from scan to receiving results was 30.5 ± 32 days, 14 days sooner than in the face-to-face group (p = 0.0016). The average round-trip distance travelled by patients to the hospital for results of their scans was 256 ± 131 km. CONCLUSION: The telephone clinic led to a significant reduction in time until patients received their scan results and helped reduce travel distance and clinic numbers in traditional face-to-face clinics.

Incidence and survival rates and trends of skull Base chondrosarcoma: A Population-Based study.

INTRODUCTION: Chondrosarcomas are extremely rare, locally invasive, and potentially mortal malignant cartilaginous tumors. In this study, we aimed to evaluate the incidence and survival rates and trends of skull base chondrosarcomas (SBC). METHODS: Data from SBC patients between 1975 and 2017 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. The age-adjusted incidence rates (AAR) were calculated for the overall cases and based on gender, age, race, and histology. Furthermore, the relative survival rates for one, three, and five years, and the rates stratified to the aforementioned selected variables were computed. Besides, we conducted a joint point regression analysis to calculate the annual percent change (APC) and its associated standard error (SE) for AAR and mortality. RESULTS: The AAR rate of SBC was 0.019 per 100,000. Higher AAR rates were observed in patients who were in the 65-74-year-age-group, females, Caucasians, and had none mesenchymal subtype. The relative one-year, three-year and five-year-survival rates were 99.58 %, 93.67 %, and 89.10 %, respectively. Lower survival rates were noted in patients who were males, African Americans, and had a mesenchymal subtype. The trend analysis has shown a significant yearly increase (P < 0.001) in AAR of SBC (APC ±â€¯SE = 0.0005 %±0.0001), along with a significant yearly decline in mortality rates (APC ±â€¯SE= -0.0202 %±0.0029). CONCLUSION: Despite the increase in AAR over time, there has been a significant decline in mortality rates over time, which might have been due to the advancement of treatment modalities, improvement in diagnostic imaging, and modification in disease grading.

Squamous Cell Carcinoma and Its Variants.

Squamous cell carcinoma (SCC) is one of the most common malignant neoplasms involving the anterior skull base, resulting from local invasion from an adjacent anatomical region. The primary sites of origin are most frequently the nasal cavity and paranasal sinuses, and less often the skin and orbit. Treatment strategies for these tumors have evolved, although management remains challenging due to the proximity to critical structures and their location at the intracranial-extracranial interface. The rarity of these tumors, and limited numbers at any one institution, has meant that most published series have grouped together different histologies in reporting outcomes. Data on SCC alone are thus limited. Treatment of SCC involving the anterior skull involves a multidisciplinary team approach. A number of potential treatment options exist, dependent on tumor, patient, and institutional factors. Current treatment strategies commonly involve multimodality therapy using a combination of surgery, radiotherapy, and chemotherapy. Primary surgery is considered the mainstay of initial treatment in those tumors which are deemed resectable, followed by adjuvant radiotherapy with or without chemotherapy. Preoperative assessment includes confirmation of the tissue diagnosis, and imaging to assess resectability, guide the surgical approach, and to plan the extent of surgery and method of reconstruction. Analysis of our institutional database for patients undergoing surgery with SCC involving the anterior skull base showed a 5-year disease-specific survival of 65% for sinonasal SCC and 71% for cutaneous SCC. The surgical margin status as well as dural and pterygopalatine fossa involvement were predictors of a poor prognosis.

Management of incidental anterior skull base large and giant meningiomas in elderly patients.

INTRODUCTION: The incidence of meningiomas among the elderly is considered to be high, and are at increased risk of severe morbidity and mortality following surgery due to their aging physiology and unexpected comorbidities. This study aimed to evaluate the optimal management strategies of meningiomas in elderly patients. METHODS: We retrospectively analyzed 150 patients with incidental large (≥ 3 cm) and giant (≥ 6 cm) anterior skull base meningiomas from 2009 to 2018. These patients were divided into elderly group (≥ 65 years, n = 70) and younger group (< 65 years, n = 80). Information of patients with regard to their medical records, operative details, relevant imaging, and follow-up data were obtained from their respective electronic medical records. RESULTS: The elderly patients had significantly longer length of hospital stay (15.9 ± 3.5) compared to younger patients (13.6 ± 3.6, P < 0.001). Karnofsky Performance Scale (KPS) at discharge was significantly lower in elderly group when compared to younger group (P = 0.04). However, the KPS at 1-year after surgery was similar between the two groups. In addition, there was no significant difference in the incidence of surgical complications between the two groups. Multivariate regression analysis of postoperative complications revealed blood loss ≥ 800 mL (P = 0.007) and BMI (< 18.5 or ≥ 24, P < 0.001) as risk factors, rather than age. CONCLUSIONS: Surgical resection in elderly patients with incidental anterior skull base large and giant meningiomas is considered to be a safe and effective therapeutic option owing to acceptable mortality, postoperative complications and postoperative clinical outcomes.

Clinical findings in families with chordoma with and without T gene duplications and in patients with sporadic chordoma reported to the Surveillance, Epidemiology, and End Results program.

OBJECTIVE: To gain insight into the role of germline genetics in the development of chordoma, the authors evaluated data from 2 sets of patients with familial chordoma, those with and without a germline duplication of the T gene (T-dup+ vs T-dup-), which was previously identified as a susceptibility mechanism in some families. The authors then compared the patients with familial tumors to patients with sporadic chordoma in the US general population reported to the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program through 2015. METHODS: Evaluation of family members included review of personal and family medical history, physical and neurological examination, and pre- and postcontrast MRI of the skull base and spine. Sixteen patients from 6 white families with chordoma had a chordoma diagnosis at family referral. Screening MR images of 35 relatives revealed clival lesions in 6, 4 of which were excised and confirmed to be chordoma. Thus, data were available for 20 patients with histologically confirmed familial chordoma. There were 1759 patients with histologically confirmed chordoma in SEER whose race was known. RESULTS: The median age at chordoma diagnosis differed across the groups: it was lowest in T-dup+ familial patients (26.8 years, range 5.3-68.4 years); intermediate in T-dup- patients (46.2 years, range 11.8-60.1 years); and highest in SEER patients (57 years, range 0-98 years). There was a marked preponderance of skull base tumors in patients with familial chordoma (93% in T-dup+ and 83% in T-dup-) versus 38% in the SEER program (37% in white, 53% in black, and 48.5% in Asian/Pacific Islander/American Indian/Alaska Native patients). Furthermore, 29% of white and 16%-17% of nonwhite SEER patients had mobile-spine chordoma, versus no patients in the familial group. Several T-dup+ familial chordoma patients had putative second/multiple primary chordomas. CONCLUSIONS: The occurrence of young age at diagnosis, skull base presentation, or multiple primary chordomas should encourage careful review of family history for patients diagnosed with chordoma as well as screening of at-risk family members by MRI for early detection of chordoma. Furthermore, given genetic predisposition in some patients with familial chordoma, identification of a specific mutation in a family will permit surveillance to be limited to mutation carriers-and consideration should be given for imaging the entire neuraxis in any chordoma patient presenting at an early age or with a blood relative with chordoma. Finally, future studies should explore racial differences in age at diagnosis and presenting site in chordoma.

Endoscopic Anterior Skull Base Reconstruction: A Meta-Analysis and Systematic Review of Graft Type.

OBJECTIVE: The influence of graft type (nonautologous vs. autologous) on surgical outcomes in endoscopic anterior skull base (EASB) reconstruction is not well understood. This review systematically evaluated rates of postoperative complications of EASB repairs that utilized autologous or nonautologous grafts. METHODS: Original studies reporting EASB reconstruction outcomes were extracted from PubMed, Ovid, and the Cochrane Library from database inception to 2019. Risk ratios, risk differences, χ2 tests, and multivariate logistic regression were used to evaluate outcome measures: postoperative cerebrospinal fluid (CSF) leaks, meningitis, and other major complications (OMCs). RESULTS: A total of 2275 patients from 29 studies were analyzed. Rates of postoperative CSF leaks, meningitis, and OMCs were 4.0%, 1.6%, and 2.3%, respectively, using autologous grafts, and 5.0%, 0.3%, and 1.0%, respectively, using nonautologous grafts. Multivariate analysis of 118 patients demonstrated no significant differences in age, CSF flow rate, single or multilayer reconstruction, and presence of intraoperative CSF leak or lumbar drain. Meta-analyses of 6 studies yielded a risk ratio of 0.64 (95% confidence interval [CI], 0.19-2.14; P = 0.47) for postoperative CSF leakage, and risk differences of -0.01 (95% CI, -0.06 to 0.05; P = 0.80) and -0.02 (95% CI, -0.09 to 0.05; P = 0.51) for postoperative meningitis and OMCs, respectively. There were no significant differences in postoperative CSF leakage (P = 0.95) and OMCs (P = 0.41) between graft types among cases with intraoperative CSF leaks. However, meningitis rates were lower (P = 0.04) in the nonautologous group. CONCLUSIONS: EASB reconstructions utilizing autologous and nonautologous grafts are associated with similar rates of postoperative CSF leakage and OMCs. In cases with intraoperative CSF leakage, nonautologous grafts were associated with reduced postoperative meningitis.

Clinical features of newly developed NF2 intracranial meningiomas through comparative analysis of pediatric and adult patients.

OBJECTIVE: NF2 patients can develop new meningiomas throughout their lifetime. Little is known about the clinical features of newly developed NF2 meningiomas. In this study, we analyzed newly developed NF2 meningiomas in a large patient population. PATIENTS AND METHODS: Among 452 NF2 patients, the location patterns of 81 pediatric and 939 adult NF2 meningiomas were compared to find the predominant locations of newly developed meningiomas in adulthood. The clinical features of 39 newly developed meningiomas in 24 NF2 patients were summarized. Clinical risk factors of NF2 meningioma growth rates were analyzed. RESULTS: Pediatric patients had significantly more intracranial meningiomas than adult patients at the skull base (except for the petrosal region) (p < 0.0063). Adult patients had significantly more cranial meningiomas than pediatric patients at the parasagittal, parafalcine (middle & posterior), and frontal/parietal/cerebellar convex surfaces (p < 0.0063). Newly developed NF2 meningiomas in adults tended to occur at different locations than the locations of NF2 meningiomas in pediatric patients. New meningiomas could develop at various ages. Ninety-five NF2 patients were imaged and followed up for at least one year. Twenty-four patients (25.3 %) developed 39 new meningiomas during the follow-up period. They usually had initial meningiomas when new meningiomas occurred. The number of newly developed meningiomas per patient and the petrosal location were significantly associated with both the absolute and relative annual growth rates (p < 0.05). CONCLUSIONS: The number of newly developed NF2 meningiomas seems to be a clinical marker of NF2 disease severity. In adults, new NF2 meningiomas tend to occur in patients with initial meningiomas. The predominant locations of newly developed NF2 meningiomas seem to be the parasagittal, parafalcine (middle/posterior), and frontal/parietal/cerebellar convex surfaces.

Pneumosinus Dilatans: An exploration into the association between Arachnoid Cyst, Meningioma and the pathogenesis of Pneumosinus Dilatans.

OBJECTIVES: To investigate the association between certain intracranial masses (meningioma and arachnoid cyst) and the incidence of Pneumosinus Dilatans (PSD) - including whether the size of the mass correlates with severity of the condition. PATIENTS AND METHODS: A review of the available case reports on PSD was performed. Clinical data was extracted from 111 case reports for analysis. A further case-control study was performed using CT Head datasets to investigate the aetiological relationship between intracranial masses and PSD. Cases included patients with confirmed arachnoid cyst or meningioma. Controls included patients with no intracranial masses. RESULTS: PSD is most common in the frontal (48%) and sphenoid sinuses (43%). Men are twice as likely to be affected as women. 58% of cases occur in patients aged 35 or under. The most common symptoms reported are facial deformities (39%), headache (24%) and visual loss (15%). Unexplained visual changes (e.g. diplopia, reduced visual acuity) are strongly correlated with sphenoid sinus involvement. PSD is more common in patients with skull-base meningioma (OR 5.67) and middle cranial fossa arachnoid cysts (OR 10.00). Mean sinus volume in patients with PSD can increase by up to 4 times. CONCLUSION: We present the first direct investigation into the relationship between meningioma, arachnoid cyst and Pneumosinus Dilatans. There is a statistical correlation between skull-base meningioma and middle cranial fossa arachnoid cysts and the incidence of PSD. This specific anatomical relation suggests that local factors contribute to the pathogenesis of the condition. Alterations in intracranial pressure due to mass effect or vascular occlusion, in addition to the localised release of bone growth factors (IGF-1, IGF-2, PDGF), are possible mechanisms for this. The first peak in incidence of PSD coincides with the completion of normal sinus pneumatisation, which raises the further possibility that predisposing genetic factors also contribute.

Skull Base Enchondroma and Chondrosarcoma in Ollier Disease and Maffucci Syndrome.

BACKGROUND: Maffucci syndrome (MS) and Ollier disease (OD) are rare diseases characterized by multiple benign enchondromas. The incidence of skull base (SB) enchondromas and the risk of malignant transformation remain unknown. Most SB lesions are asymptomatic, and surgical resection carries significant morbidity. Observation may be a reasonable strategy. We report our experience with observation of probable SB enchondromas in MS/OD patients. METHODS: Retrospective review of OD/MS patients with cranial imaging between 1995 and 2018 at 1 institution. RESULTS: 14 patients were included: 3 with MS (21.4%) and 11 with OD (78.6%). The median age was 28 years (range, 11-74 years) and 57.1% were female. Extracranial chondrosarcoma was reported in 3 (21.4%) patients. Seven (50%) patients with SB enchondroma or chondrosarcoma were identified on initial imaging. In patients with SB lesions, the indications for imaging were headache (n=3), seizure (n=1), and diplopia (n=1); 2 cases were incidental findings. The most commonly involved structures were petroclival fissure (86%) and clivus (71%). Treatment included observation (6/7) and resection (1/7). Follow-up imaging was available for all SB lesions, with a mean interval of 50.7 months (range, 5-225 months) and was negative for progression in all patients. CONCLUSIONS: Primary SB lesions in OD/MS patients frequently present in the petroclival junction. Cranial screening and close observation should be considered in MS/OD patients, given the increased risk of intra-axial intracranial tumors, de novo chondrosarcomas, or malignant degeneration of previously known lesions. In asymptomatic patients, observation appears to be a safe strategy in this cohort. Further case accumulation and follow-up are required to better understand the long-term outcomes.

Clinical features, radiological profiles, and surgical outcomes of primary intracranial solitary plasmacytomas: a report of 17 cases and a pooled analysis of individual patient data.

PURPOSE: We aim to delineate the clinical characteristics of patients with primary intracranial solitary plasmacytoma (PISPC) and prognostic factors for their outcomes. METHODS: This study retrospectively reviewed 17 patients with PISPC from our center and an additional 70 cases of PISPC published previously to analyze outcome predictors. RESULTS: The entire cohort included 38 (43.7%) males and 49 (56.3%) females with a mean age of 54 years. Skull base tumors were found in 49 (56.3%) patients. Gross total resection (GTR) was achieved in 31 (35.6%) patients. Postoperative adjuvant treatments, including radiotherapy (RT) alone, chemotherapy (CMT) alone, and RT + CMT were administered in 49 (56.3%) patients, 3 (3.5%) patients, and 16 (18.4%) patients, respectively. After a median follow-up of 24 (mean 42.4) months, the 5-year disease progression-free survival (PFS), recurrence-free survival (RFS), multiple myeloma (MM)-free survival (MMFS), and overall survival (OS) were 52.9%, 76.2%, 69.6%, and 76.1%, respectively. Multivariate analysis unveiled that a skull base tumor location (HR 2.395, p = 0.040) and no RT (HR 3.115, p = 0.004) were negative prognostic factors for PFS, no RT (HR 10.526, p = 0.003) for RFS, each 1-year increase in age (HR 1.039, p = 0.049) for MMFS, and increasing age (HR 1.052, p = 0.043) and CMT (HR 6.022, p = 0.005) were risk factors for OS. However, GTR did not benefit the aforementioned outcomes. CONCLUSION: For patients with presumed PISPC, a biopsy followed by RT is recommended for skull base PISPC. However, the role of CMT is still not clear. Our findings need to be verified in a larger prospective cohort in the future. Systematic review registration number CRD42018098782.

Chordoma: a systematic review of the epidemiology and clinical prognostic factors predicting progression-free and overall survival.

BACKGROUND AND AIMS: The aim of this systematic review is to describe the epidemiology of chordoma and to provide a clear overview of clinical prognostic factors predicting progression-free and overall survival. METHODS: Four databases of medical literature were searched. Separate searches were performed for each of the two objectives. Reference and citation tracking was performed. Papers were processed by two independent reviewers according to a protocol that included risk of bias analysis. Disagreement was resolved by discussion. Pooled analyses were planned if homogeneity of data would allow. RESULTS: Incidence-incidence rates ranged between 0.18 and 0.84 per million persons per year and varied between countries and presumably between races. On average patients were diagnosed in their late fifties and gender data indicate clear male predominance. Two of the largest studies (n = 400 and n = 544) reported different anatomical distributions: one reporting the skull base and sacrococcygeal area affected in 32% and 29% of cases, whereas the other reporting that they were affected in 26% and 45% of cases, respectively. PROGNOSTIC FACTORS: Statistically significant adverse prognostic factors predicting progression-free and overall survival include female sex, older age, bigger tumour size, increasing extent of tumour invasion, non-total resection, presence of metastasis, local recurrence, and dedifferentiated histological subtype. CONCLUSIONS: Incidence rate and anatomical distribution vary between countries and presumably between races. Most chordomas arise in the skull base and sacrococcygeal spine, and the tumour shows clear male predominance. Multiple adverse prognostic factors predicting progression-free and overall survival were identified in subgroups of patients. These slides can be retrieved under Electronic Supplementary Material.

Arrested pneumatization of the sphenoid sinus mimicking skull base tumours: MRI prevalence in children with haematologic diseases.

Objective: Arrested pneumatization of the sphenoid sinus is a developmental anatomic variation but may be confused with serious diseases of the skull base. The purpose of this study was to investigate the prevalence of arrested pneumatization of the sphenoid sinus in paediatric patients with haemotologic diseases like sickle cell anaemia, thalassemia and leukemia. Materials and Methods: One hundred and eight paediatric patients (43 girls, 65 boys; age range: 4-18 years; median age: 13 years) with haemotologic diseases who underwent at least one magnetic resonance imaging of the head and neck between 2010 and 2017 in a single institution were included. Magnetic resonance imaging studies were retrospectively reviewed. Well-defined and fat-containing non-expansile lesions located at the sphenoid sinus region were diagnosed as arrested pneumatization of the sphenoid sinus. Medical diagnoses, lesion sizes, age and sex of the patients were recorded. Results: Five (4.6%) of 108 patients demonstrated arrested pneumatization of the sphenoid sinus (3 girls, 2 boys; age range: 9-18 years; median age: 14 years). One (1.2%) of 83 patients with acute leukemia, 2 (15%) of 13 patients with sickle cell anaemia and 2 of 12 (17%) patients with thalassemia demonstrated arrested pneumatization of the sphenoid sinus. No statistical correlation was found between arrested pneumatization of the sphenoid sinus and possible risk factors like patient age and sex. Conclusions: Patients with haemoglobinopathies like sickle cell anaemia and thalassemia involving red-blood-cells had higher prevalence of arrested pneumatization of the sphenoid sinus than patients with leukemia which involves the white-blood-cells. This supported the suggestion that regional blood-flow disorders induce arrested pneumatization of the sphenoid sinus. Correct diagnosis prevents invasive procedures like biopsy and surgery.

Intracranial dural, calvarial, and skull base metastases.

Metastatic disease to the intracranial dura, the calvarium, and the skull base is relatively uncommon but presents unique diagnostic and management challenges in the patient with cancer. Modern imaging techniques have facilitated the detection of intracranial tumor deposits, leading to increased incidence. While dural and calvarial metastases often present with nonspecific symptoms, skull base metastases present with distinct clinical syndromes dependent on the local neurovascular structures affected. Intracranial dural metastases can often be confused with meningioma and pose a diagnostic challenge, as well as significant neurologic morbidity, especially in the setting of hemorrhage. Surgical intervention may be helpful in selected patients for symptomatic relief as well as survival benefit. Management paradigms need to take into account the relative risks, benefits, and likely outcomes for each possible modality of treatment. Surgical excision is useful in many patients and in combination with radiation therapy can provide significant palliation. While medical therapy is rarely an initial therapy in these entities, it may be of added benefit dependent on the underlying tumor histology and prior treatment history. Occasionally treatment with curative intent is justified.

Long-term control and predictors of seizures in intracranial meningioma surgery: a population-based study.

BACKGROUND: The aim of this retrospective study was to investigate the long-term seizure control and antiepileptic drug (AED) prescriptions, as well as identifying predictors of seizure(s) before and after surgery in a population-based cohort of operated intracranial meningioma patients. METHODS: A total of 113 consecutive adult (> 18 years old) patients with newly diagnosed meningioma operated at the Karolinska University Hospital between 2006 and 2008 were included and followed up until the end of 2015. Data on seizure activity and AED prescriptions were obtained through chart review and telephone interview. Logistic regression and survival analysis were applied to identify risk factors for pre- and postoperative seizures. RESULTS: A total of 21/113 (18.6%) patients experienced seizures before surgery of which 8/21 (38.1%) went on to become seizure-free after surgery. Thirteen (14%) patients experienced new-onset seizures after surgery. The regression analysis revealed tumor diameter ≥ 3.5 cm as a risk factor for preoperative seizures (OR 3.83, 95% CI 1.14-12.87). Presence of headache (OR 0.19, 95% CI 0.05-0.76) and skull base tumor location (OR 0.14, 95% CI 0.04-0.44) decreased the risk of preoperative seizures. Postoperative seizures were associated with tumor diameter ≥ 3.5 cm (OR 2.65, 95% CI 1.06-6.62) and history of preoperative seizures (OR 3.50, 95% CI 1.55-7.90). CONCLUSION: Seizures are common before and after intracranial meningioma surgery. Approximately one third of patients with preoperative seizures become seizure-free on long-term follow-up after surgery, while 14% experienced new-onset seizures after surgery. Larger tumor size, absence of headache, and non-skull base location were associated with preoperative seizures, while tumor size and preoperative seizures were associated with postoperative seizures.

Iatrogenic seeding of skull base chordoma following endoscopic endonasal surgery.

OBJECTIVE: Iatrogenic tumor seeding after open surgery for chordoma has been well described in the literature. The incidence and particularities related to endoscopic endonasal surgery (EES) have not been defined. METHODS: The authors retrospectively reviewed their experience with EES for clival chordoma, focusing on cases with iatrogenic seeding. The clinical, radiographic, pathological, and molecular characterization data were reviewed. RESULTS: Among 173 EESs performed for clival chordomas at the authors' institution between April 2003 and May 2016, 2 cases complicated by iatrogenic seeding (incidence 1.15%) were identified. The first case was a 10-year-old boy, who presented 21 months after an EES for a multiply recurrent clival chordoma with a recurrence along the left inferior turbinate, distinct from a right petrous apex recurrence. Both appeared as a T2-hypertintense, T1-isointense, and heterogeneously enhancing lesion on MRI. Resection of the inferior turbinate recurrence and debulking of the petrous recurrence were both performed via a purely endoscopic endonasal approach. Unfortunately, the child died 2 years later due progression of disease at the primary site, but with no sign of progression at the seeded site. The second patient was a 79-year-old man with an MRI-incompatible pacemaker who presented 19 months after EES for his clival chordoma with a mass involving the floor of the left nasal cavity that was causing an oro-antral fistula. On CT imaging, this appeared as a homogeneously contrast-enhancing mass eroding the hard palate inferiorly, the nasal septum superiorly, and the nasal process of the maxilla, with extension into the subcutaneous tissue. This was also treated endoscopically (combined transnasal-transoral approach) with resection of the mass, and repair of the fistula by using a palatal and left lateral wall rotational flap. Adjuvant hypofractionated stereotactic CyberKnife radiotherapy was administered using 35 Gy in 5 fractions. No recurrence was appreciated endoscopically or on imaging at the patient's last follow-up, 12 months after this last procedure. In both cases, pathological investigation of the original tumors revealed a fairly aggressive biology with 1p36 deletions, and high Ki-67 levels (10%-15%, and > 20%, respectively). The procedures were performed by a team of right-handed surgeons (otolaryngology and neurosurgery), using a 4-handed technique (in which the endoscope and suction are typically passed through the right nostril, and other instruments are passed through the left nostril without visualization). CONCLUSIONS: Although uncommon, iatrogenic seeding occurs during EES for clival chordomas, probably because of decreased visualization during tumor removal combined with mucosal trauma and exposure of subepithelial elements (either inadvertently or because of mucosal flaps). In addition, tumors with more aggressive biology (1p36 deletions, elevated Ki-67, or both) are probably at a higher risk and require increased vigilance on surveillance imaging and endoscopy. Further prospective studies are warranted to evaluate the authors' proposed strategies for decreasing the incidence of iatrogenic seeding after EES for chordomas.

Pediatric Clival Chordoma: A Curable Disease that Conforms to Collins' Law.

BACKGROUND: Skull base chordomas in children are extremely rare. Their course, management, and outcome have not been defined. OBJECTIVE: To describe the preeminent clinical and radiological features in a series of pediatric patients with skull base chordomas and analyze the outcome of a cohort who underwent uniform treatment. We emphasize predictors of overall survival and progression-free survival, which aligns with Collins' law for embryonal tumors. METHODS: Thirty-one patients with a mean age of 10.7 yr (range 0.8-22) harboring skull base chordomas were evaluated. We retrospectively analyzed the outcomes and prognostic factors for 18 patients treated by the senior author, with uniform management of surgery with the aim of gross total resection and adjuvant proton-beam radiotherapy. Mean follow-up was 119.2 mo (range 8-263). RESULTS: Abducens nerve palsy was the most common presenting symptom. Imaging disclosed large tumors that often involve multiple anatomical compartments. Patients undergoing gross total resection had significantly increased progression-free survival (P = .02) and overall survival (P = .05) compared with those having subtotal resection. Those who lived through the period of risk for recurrence without disease progression had a higher probability of living entirely free of progression (P = .03; odds ratio = 16.0). Age, sex, and histopathological variant did not yield statistical significance in survival. CONCLUSION: Long-term overall and progression-free survival in children harboring skull base chordomas can be achieved with gross surgical resection and proton-beam radiotherapy, despite an advanced stage at presentation. Collins' law does apply to pediatric skull base chordomas, and children with this disease have a high hope for cure.

Multimodality Treatment of Skull Base Chondrosarcomas: The Role of Histology Specific Treatment Protocols.

BACKGROUND: Limited data exist to guide the multimodality management of chondrosarcomas (CSAs) arising in the skull base. OBJECTIVE: To determine the impact of histological subtype/grade on progression-free survival (PFS) and the indications for surgery, radiation, and chemotherapy based on histology. METHODS: A retrospective review was performed of 37 patients (conventional type: 81%, mesenchymal: 16.2%, dedifferentiated: 2.7%) treated at The University of Texas M.D. Anderson Cancer Center. Of the conventional subtype, 23% were grade 1, 63% were grade 2, and 14% were grade 3. In addition to surgery, mesenchymal/dedifferentiated CSAs (18% of the cohort) underwent neoadjuvant chemotherapy and 48.6% of the overall cohort received adjuvant radiotherapy. Histological grade/subtype and treatment factors were assessed for impact on median PFS (primary outcome). RESULTS: Conventional subtype vs mesenchymal/dedifferentiated was positively associated with median PFS (166 vs 24 months, P < .05). Increasing conventional grade inversely correlated with median PFS ( P < .05). Gross total resection positively impacted PFS in conventional CSAs (111.8 vs 42.9 months, P = .201) and mesenchymal/dedifferentiated CSAs (58.2 vs 1.0 month, P < .05). Adjuvant radiotherapy significantly impacted PFS in conventional grades 2 and 3 (182 vs 79 months, P < .05) and a positive trend with mesenchymal/dedifferentiated CSAs (43.5 vs 22.0 months). Chemotherapy improved PFS for mesenchymal/dedifferentiated CSAs (50 vs 9 months, P = .089). CONCLUSION: There is a potential need for histological subtype/grade specific treatment protocols. For conventional CSAs, surgery alone provides optimal results grade 1 CSAs, while resection with adjuvant radiotherapy yields the best outcome for grade 2 and 3 CSAs. Improvements in PFS seen with neoadjuvant therapy in mesenchymal/dedifferentiated CSAs indicate a potential role for systemic therapies. Larger studies are necessary to confirm the proposed treatment protocols.

Primary Lymphomas of the Skull Base from a Neurosurgical Perspective: Review of the Literature and Personal Experience.

Primary lymphomas of the skull base are exceedingly rare and thus not commonly dealt with in everyday clinical practice. Primary diffuse large B cell lymphoma is the most commonly found (30-40% of primary non-Hodgkin lymphomas of the bone). This article reports a case of primary lymphoma of the skull base and reviews all the relevant literature in the PubMed, National Institutes of Health Library, and Google Scholar databases to outline the clinical, diagnostic, and surgical traits of this yet widely unexplored pathology. The incidence of cases peaks between 60 and 70 years of age; those affected tend to be mostly male. The clinical presentation of this pathology is usually abrupt with headache and acute deficit of cranial nerves that improves dramatically with intravenous corticosteroid therapy. The abducens nerve is most commonly involved. Imaging can be unclear because corticosteroid medications can significantly alter magnetic resonance imaging findings, at least in the early stages of the disease, similarly to what happens for primary brain lymphomas ("the ghost tumor"). Cavernous sinus, parasellar region, upper clivus, and Meckel cave are usually found to be already affected by the time a diagnosis can be made. The intracavernous internal carotid artery is usually encased by the lesion rather than displaced. Because of the anatomical pattern of primary lymphomas of the skull base and their well-known chemosensitivity, surgery is usually only used for diagnosis. Surgical approaches for primary lymphoma of the skull base include transcranial and transnasal-transsphenoidal endoscopy and microsurgery as well as other minimally invasive techniques. Due to the rarity of this neoplasm, there are no definitive data regarding the overall survival rate among patients.

[Etiology and pathogenesis of glomus tumours (chemodectomas) of the base of the skull].

The objective of the present work was to describe the poorly known history of the development of the nomenclature of glomus tumours (chemodectomas) of the base of the skull, elucidate etiology and pathogenesis of these neoplasms. The authors present a chronological table illustrating the progress of etiological and pathogenetic studies as well as the surgical treatment of the tumours. The results of analysis and discussion of the controversial issues of the nomenclature are reported.