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Cancer Control : Journal of the Moffitt... Jul 2016The unique radiobiological properties of protons have been understood for many years. In addition, many of the clinical benefits of radiotherapy were first noted in... (Review)
Review
BACKGROUND
The unique radiobiological properties of protons have been understood for many years. In addition, many of the clinical benefits of radiotherapy were first noted in tumors involving the skull base. More public attention has been given to proton beam therapy due to the increasing number of centers now in operation or in the planning stages for offering this treatment option.
METHODS
We reviewed the physical properties of protons and the clinical studies performed to justify their use in the management of skull-base tumors and determine the benefits of proton beam therapy.
RESULTS
Published reports suggest a benefit to proton beam therapy for use in tumors of the skull base, including craniopharyngiomas, chordomas, skull-base sarcomas, and unresectable meningiomas.
CONCLUSIONS
Use of proton beam therapy may be beneficial in select patients. Surgical and medical oncologists should have a general understanding of such cases to facilitate their appropriate referral.
Topics: Female; Humans; Proton Therapy; Radiotherapy Dosage; Skull Base Neoplasms
PubMed: 27556661
DOI: 10.1177/107327481602300304 -
Chinese Clinical Oncology Jul 2017Skull base meningiomas (SBM) pose unique challenges for radiotherapy as these tumors are often in close proximity to a number of critical structures and may not be... (Review)
Review
Skull base meningiomas (SBM) pose unique challenges for radiotherapy as these tumors are often in close proximity to a number of critical structures and may not be surgically addressed in many cases, leaving the question about the tumor grade and expected biological behaviour. External beam radiotherapy and radiosurgery are longstanding treatments for meningioma that are typically used as upfront primary therapy, for recurrent tumors and as adjuvant therapy following surgical resection. There is controversy regarding the optimal timing and approach for radiation therapy in various clinical settings such as the role of adjuvant radiotherapy for completely resected grade 2 tumours. Despite the use of radiotherapy for many decades, the evidence to guide optimal radiation treatment is limited largely to single institution series of EBRT, SRS and particle therapy. In this article, we review the published data to clarify the role of external beam radiotherapy, proton radiotherapy and single and multi-fraction radiosurgery for SBM. We also highlight the areas of potential research and need for clinical improvement, including the growing awareness and effort to improve cognitive function in this patient population, who typically have long life expectancy following their meningioma diagnosis.
Topics: Humans; Meningeal Neoplasms; Meningioma; Radiotherapy; Skull Base Neoplasms
PubMed: 28758407
DOI: 10.21037/cco.2017.06.08 -
Zhurnal Voprosy Neirokhirurgii Imeni N.... 2017The purpose of this review is to analyze used anterior midline approaches to the skull base, identify their advantages and disadvantages, and, after reviewing the... (Review)
Review
The purpose of this review is to analyze used anterior midline approaches to the skull base, identify their advantages and disadvantages, and, after reviewing the literature data, submit a developed algorithm for choosing an optimal approach to the approval of colleagues. We provide brief information on approach techniques, indications and contraindications, and advantages and disadvantages as well as analyze international experience of using the discussed approaches. On the basis of literature data, we have developed a prototype algorithm for choosing an optimal approach to medial tumors of the anterior skull base. The situation of choosing an optimal approach reveals the absence of a clear understanding of the boundaries between capabilities and limitations of approaches. To solve this problem, an original prospective study is required.
Topics: Algorithms; Craniotomy; Humans; Models, Anatomic; Skull Base; Skull Base Neoplasms
PubMed: 28524132
DOI: 10.17116/neiro2017812103-112 -
Journal of Medical Case Reports Aug 2018Chordoma is a rare malignant tumor of the skull base and axial skeleton, with an incidence of less than 0.1/100,000 per year. Patients with advanced chordoma have a poor... (Review)
Review
BACKGROUND
Chordoma is a rare malignant tumor of the skull base and axial skeleton, with an incidence of less than 0.1/100,000 per year. Patients with advanced chordoma have a poor prognosis due to locoregional recurrence with infiltration and destruction of surrounding bone and soft tissue. Cytotoxic chemotherapy or other systemic therapies have not been proven to be effective for these diseases. Therefore, several molecularly targeted therapies have been proposed as potentially beneficial, including tyrosine kinase inhibitors such as imatinib, sorafenib, lapatinib, and others.
CASE PRESENTATION
We present three cases of advanced chordoma treated with molecular targeted therapies: a 52-year-old Caucasian man, a 72-year-old Caucasian woman, and a 38-year-old Caucasian woman.
CONCLUSIONS
Chordoma has few systemic treatment options and they have limited benefit. Randomized trials with large patient numbers are unfeasible in this rare disease. Targeted therapy might be a reasonable alternative treatment for chordoma. Still, new treatment strategies are needed for this rare disease.
Topics: Adult; Aged; Bone Neoplasms; Chordoma; Cranial Fossa, Posterior; Female; Humans; Imatinib Mesylate; Male; Middle Aged; Molecular Targeted Therapy; Neoplasm Recurrence, Local; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Sacrum; Skull Base Neoplasms; Spinal Neoplasms; Sunitinib
PubMed: 30145982
DOI: 10.1186/s13256-018-1784-y -
Neurosurgery Jun 2022Accurate specimen analysis of skull base tumors is essential for providing personalized surgical treatment strategies. Intraoperative specimen interpretation can be...
BACKGROUND
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.
OBJECTIVE
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.
METHODS
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.
RESULTS
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.
CONCLUSION
SRH with trained artificial intelligence models can provide rapid and accurate intraoperative analysis of skull base tumor specimens to inform surgical decision-making.
Topics: Artificial Intelligence; Brain Neoplasms; Humans; Meningeal Neoplasms; Optical Imaging; Skull Base Neoplasms
PubMed: 35343469
DOI: 10.1227/neu.0000000000001929 -
Chinese Clinical Oncology Dec 2020Management of solid tumors involving the skull base are primarily managed with surgery and radiation, though proximity to important vascular and neuroanatomic structures... (Review)
Review
Management of solid tumors involving the skull base are primarily managed with surgery and radiation, though proximity to important vascular and neuroanatomic structures often limit the extent of resection and permissible radiation dose. Meningiomas are the most common primary brain tumor in adults, and although the majority of skull base meningiomas are low-grade, their location in proximity to critical anatomical structures precludes aggressive surgical resection, and larger tumors are often resistant to radiation treatment. In patients with clinically aggressive, unresectable meningiomas, several molecular biomarkers of angiogenesis, as well as genetic mutations (SMO, AKT1, PIK3CA, KLF4, POLR2, SMARCE1, and TRAF7), have been shown to play a crucial role in the pathophysiology of these tumors. Pituitary adenomas are commonly slow growing tumors that are amenable to surgical resection, but tumors with higher Ki67 proliferative indices are associated with an increased risk of relapse and resistance to standard therapies. Chemotherapeutic agents and checkpoint inhibitors have been trialed, albeit with limited success, to treat these aggressive pituitary adenomas. Craniopharyngiomas are categorized as adamantinomatous and papillary subtypes, each with unique molecular mechanisms that drive pathogenesis of these tumors, and have introduced the possibility that targeted therapies may be developed for improved neurologic and endocrinological outcomes. Skull base tumors that exhibit recurrence despite surgical resection and radiation treatment pose a unique challenge, and systemic agents offer a non-invasive option of treating tumors that are refractory to conventional approaches. Recent insights into the molecular aberrations that elucidate the pathophysiology of these difficult-to-treat tumors have provided potential therapeutic targets for drug delivery. In this review, the authors discuss promising therapies and current knowledge gaps needed for the development of effective targeted agents for meningioma, pituitary adenoma, and craniopharyngioma.
Topics: Adult; Chromosomal Proteins, Non-Histone; Craniopharyngioma; Humans; Kruppel-Like Factor 4; Meningeal Neoplasms; Meningioma; Neoplasm Recurrence, Local; Pituitary Neoplasms; Skull Base; Skull Base Neoplasms
PubMed: 32819111
DOI: 10.21037/cco-20-168 -
AJNR. American Journal of Neuroradiology Jun 2017Skull base chordoma has been widely studied in recent years, however, imaging characteristics of this tumor have not been well elaborated. The purpose of this study was...
BACKGROUND AND PURPOSE
Skull base chordoma has been widely studied in recent years, however, imaging characteristics of this tumor have not been well elaborated. The purpose of this study was to establish an MR imaging grading system for skull base chordoma.
MATERIALS AND METHODS
In this study, 156 patients with skull base chordomas were retrospectively assessed. Tumor-to-pons signal intensity ratios were calculated from pretreatment MR images R (ratio of tumor to pons signal intensity in T1 FLAIR sequence), R (ratio of tumor to pons signal intensity in T2 sequence) and R (ratio of tumor to pons signal intensity in enhanced T1 FLAIR sequence), and significant ratios for overall survival and progression-free survival were selected to establish a grading system. Clinical variables among different MR imaging grades were then analyzed to evaluate the usefulness of the grading system.
RESULTS
R ( < .001) and R ( = .04) were identified as significant variables affecting progression-free survival. After analysis, the classification criteria were set as follows: MR grade I, R > 2.49 and R ≤ 0.77; MR grade II, R > 2.49 and R > 0.77, or R ≤ 2.49 and R ≤ 0.77; and MR grade III, R ≤ 2.49 and R > 0.77. MR grade III tumors had a more abundant tumor blood supply than MR grade I tumors ( < .001), and the intraoperative blood loss of MR grade III tumors was higher than that of MR grade I tumors ( = .002). Additionally, skull base chordoma progression risk increased by 2.071 times for every single MR grade increase ( < .001).
CONCLUSIONS
A higher R value was a negative indicator of tumor progression, whereas a higher R value was a positive risk factor of tumor progression. MR grade III tumors showed a more abundant blood supply than MR grade I tumors, and the risk of skull base chordoma progression increased with every single MR grade increase.
Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Chordoma; Disease-Free Survival; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neoplasm Grading; Pons; Regional Blood Flow; Retrospective Studies; Risk Factors; Skull Base Neoplasms; Survival Analysis; Young Adult
PubMed: 28428207
DOI: 10.3174/ajnr.A5152 -
Current Status of Endoscopic Endonasal Surgery for Skull Base Meningiomas: Review of the Literature.Neurologia Medico-chirurgica 2015Endoscopic endonasal approach (EEA) is expected to be ideal for the paramedian ventral skull base meningiomas, allowing wide access to the ventral skull base regions and... (Review)
Review
Endoscopic endonasal approach (EEA) is expected to be ideal for the paramedian ventral skull base meningiomas, allowing wide access to the ventral skull base regions and realizing early devascularization of the tumor without retraction of the brain. We searched clinical reports of EEA for skull base meningiomas, written in English language, published before October 2014, using the PubMed literature search on the website. Skull base meningiomas are subdivided by the site of occurrence, olfactory groove (8 articles including 80 cases), tuberculum sellae (14 articles, 153 cases), cavernous sinus (2 articles, 8 cases), petroclival region (4 articles, 10 cases), and craniofacial region (2 articles, 5 cases), and the surgical outcomes of EEA were analyzed. In anterior skull base regions, EEA contributed to effective improvement of the symptoms in small and round-shaped meningiomas, but 25% of the patients had postoperative cerebrospinal fluid rhinorrhea. In cavernous sinus and petroclival regions, successful surgical removal largely depended on tumor consistency, and the extent of the surgical resection proportionally increased the risks of serious complications. Thus, judicious endoscopic resection with adjuvant radiotherapy or radiosurgery remains to be the most reasonable treatment option. To decrease the risks of surgical complications, the surgeons must master the closure techniques of dural defect and meticulous microsurgical procedure under endoscopic vision. Further progress will depend on the progresses of surgical technique in neurosurgeons engaging this potentially "minimally invasive" surgery.
Topics: Humans; Meningeal Neoplasms; Meningioma; Neuroendoscopy; PubMed; Skull Base Neoplasms; Treatment Outcome
PubMed: 26345667
DOI: 10.2176/nmc.ra.2015-0031 -
Zhurnal Voprosy Neirokhirurgii Imeni N.... 2016A review of literature presents up-to-date information on the prevalence, incidence, clinical manifestations, diagnosis, and classification of malignant primary skull... (Review)
Review
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.
Topics: Humans; Skull Base Neoplasms
PubMed: 28635847
DOI: 10.17116/neiro2016803106-113 -
AJNR. American Journal of Neuroradiology Aug 2018Skull base chordomas often demonstrate variable MR imaging characteristics, and there has been limited prior research investigating the potential clinical relevance of...
BACKGROUND AND PURPOSE
Skull base chordomas often demonstrate variable MR imaging characteristics, and there has been limited prior research investigating the potential clinical relevance of this variability. The purpose of this retrospective study was to assess the prognostic implications of signal intensity on standard imaging techniques for the biologic behavior of skull base chordomas.
MATERIALS AND METHODS
Medical records were retrospectively reviewed for 22 patients with pathologically confirmed skull base chordomas. Clinical data were recorded, including the degree of surgical resection, the presence or absence of radiation therapy, and time to progression/recurrence of the tumor or time without progression/recurrence of the tumor following initial treatment. Pretreatment imaging was reviewed for the presence or absence of enhancement and the T2 signal characteristics. Tumor-to-brain stem signal intensity ratios on T2, precontrast T1, and postcontrast T1 spin-echo sequences were also calculated. Statistical analysis was then performed to assess correlations between imaging characteristics and tumor progression/recurrence.
RESULTS
Progression/recurrence of skull base chordomas was seen following surgical resection in 11 of 14 (78.6%) patients with enhancing tumors and in zero of 8 patients with nonenhancing tumors. There was a statistically significant correlation between skull base chordoma enhancement and subsequent tumor progression/recurrence ( < .001), which remained significant after controlling for differences in treatment strategy ( < .001). There was also a correlation between postcontrast T1 signal intensity (as measured by postcontrast T1 tumor-to-brain stem signal intensity ratios) and recurrence/progression ( = .02). While T2 signal intensity was higher in patients without tumor progression (median tumor-to-brain stem signal intensity ratios on T2 = 2.27) than in those with progression (median tumor-to-brain stem signal intensity ratios on T2 = 1.78), this association was not significant ( = .12).
CONCLUSIONS
Enhancement of skull base chordomas is a risk factor for tumor progression/recurrence following surgical resection.
Topics: Adult; Aged; Chordoma; Contrast Media; Female; Gadolinium; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neoplasm Recurrence, Local; Prognosis; Retrospective Studies; Risk Factors; Skull Base Neoplasms
PubMed: 29903925
DOI: 10.3174/ajnr.A5714