Management of Skull Base Metastases

Surgical Treatment and Clinical Evaluation of Calvarial Metastases

BACKGROUND

The aim of this study is to explore surgical treatment techniques and clinical attributes associated with calvarial metastases, while providing a comprehensive review of the treatment experiences relevant to this particular type of tumor.

METHODS

This study involves a retrospective analysis of clinical data from 12 patients diagnosed with calvarial metastatic tumors who underwent surgical intervention. Among these patients, 5 had a history of previous malignant tumor resections, while 7 presented with calvarial metastatic tumors as their initial symptom. In all cases, the surgical approach consisted of calvarial tumor resection followed by titanium mesh repair. Following the surgical intervention, all patients underwent a comprehensive course of treatment, encompassing both local radiotherapy and systemic chemotherapy.

RESULTS

In 1 instance, a patient presented with multiple tumors located in the central area of the frontal bone and the right temporal bone. The larger tumor situated in the middle of the frontal bone was surgically excised, while the tumor in the right temporal bone was treated using radiotherapy. In 2 cases characterized by multiple metastases within the skull, a comprehensive excision of all tumors was accomplished in a single surgical procedure. In the remaining cases featuring a solitary metastatic growth, the respective tumors were surgically removed. There were 10 instances of dura mater invasion and 3 cases involving the invasion of brain tissue. Pathologic examinations revealed 1 case of metastatic lung adenocarcinoma, 1 case of metastatic paraganglioma, 1 case of metastatic hepatocellular carcinoma, 2 cases of metastatic thyroid carcinoma, and 7 cases of metastatic clear cell renal cell carcinoma. Throughout the follow-up period, spanning from 14 to 90 months, various outcomes were noted. These included three occurrences of in situ recurrence. In addition, 1 patient required 3 distinct surgical interventions, while 2 other patients underwent 2 separate surgical procedures each. Notably, 1 of these cases involved the exposure of the titanium mesh on the scalp, necessitating the removal of the titanium mesh. Regrettably, there have been 9 recorded fatalities among the patients, while 3 individuals have survived.

CONCLUSION

Solitary metastasis of calvarium region is rare, and surgical resection is effective. However, it is necessary to extend the resection range and combine with local radiotherapy to avoid local recurrence. Surgical intervention can significantly enhance the quality of life for affected patients. The prognosis of the patients mainly depends on the treatment of the primary disease and the situation of important organ dissemination and treatment.

Evaluation of diplopia as a vital and remarkable ocular finding among cancer patients

BACKGROUND

Diplopia is an important and debilitating symptom of malignancies due to different pathogenetic mechanisms. Data is lacking in the literature because of the rarity of the diplopia in patients with cancer.

AIMS

We aimed to evaluate the etiological and clinical factors of diplopia in patients with different types of cancer.

METHODS

We retrospectively investigated 22 cancer patients with diplopia who were admitted between 2018 and 2021. The diagnosis of primary cancer, the underlying factors causing diplopia, and the life expectancy after diplopia were evaluated.

RESULTS

Among available data of 620 cancer patients applied to our ophthalmology department, 22 (3.55%) had diplopia. Paralytic strabismus was found in 19 patients and restrictive strabismus was found in 3 patients. Among the paralytic cases, 6th nerve palsy was found to be the most common with a rate of 68%. In 18 of 22 (82%) patients, the cause of diplopia was due to orbital or brain metastasis or local invasion. Two patients had diplopia secondary to radiotherapy and 2 had diplopia due to chemotherapy.

CONCLUSION

Metastasis is the most common cause of diplopia in patients with cancer and screening for metastasis is crucial as soon as diplopia begins for a better life expectancy.

Neoplastic nerve lesions

Though metastasis and malignant infiltration of the peripheral nervous system is relatively rare, physicians should have a familiarity with their presentations to allow for prompt diagnosis and initiation of treatment. This article will review the clinical presentations, diagnostic evaluation, and treatment of neoplastic involvement of the cranial nerves, nerve roots, peripheral nerves, and muscle. Due to the proximity of the neural structure traversing the skull base, metastasis to this region results in distinctive syndromes, most often associated with breast, lung, and prostate cancer. Metastatic involvement of the nerve roots is uncommon, apart from leptomeningeal carcinomatosis and bony metastasis with resultant nerve root damage, and is characterized by significant pain, weakness, and numbness of an extremity. Neoplasms may metastasize or infiltrate the brachial and lumbosacral plexuses resulting in progressive and painful sensory and motor deficits. Differentiating neoplastic involvement from radiation-induced injury is of paramount importance as it dictates treatment and prognosis. Neurolymphomatosis, due to malignant lymphocytic infiltration of the cranial nerves, nerve roots, plexuses, and peripheral nerves, deserves special attention given its myriad presentations, often mimicking acquired demyelinating neuropathies.

[Skull base metastases with cranial nerve deficits : Clinical profile of a severe disease]

Hintergrund und Ziele

Schädelbasismetastasen sind eine seltene Manifestation onkologischer Erkrankungen. Wenn Hirnnerven beteiligt sind, können schon kleine Läsionen erhebliche funktionelle Beeinträchtigungen hervorrufen. Spezifische klinische Charakteristika wie neurologische Symptome, assoziierte Primärtumoren, Prognose und optimale Therapie der Erkrankung sind schlecht definiert und sollen in dieser Arbeit systematisch dargestellt werden.

Methoden

Mit einem monozentrischen retrospektiven Ansatz wurden Schädelbasismetastasen bei Patienten, die im Zeitraum von 2006 bis 2018 behandelt wurden, detailliert hinsichtlich klinischer Charakteristika, der durchgeführten Therapie und des weiteren Erkrankungsverlaufs analysiert.

Ergebnisse

Insgesamt 45 Patienten mit Schädelbasismetastasen und Hirnnervenausfällen wurden erfasst. Die häufigsten Primärtumoren waren Prostatakarzinom (27 %), Mammakarzinom (22 %) und multiples Myelom (16 %). Die am häufigsten betroffenen Hirnnerven waren Nervus trigeminus (42 %), Nervus oculomotorius (33 %) und Nervus facialis (27 %). 84 % aller Patienten wiesen außerhalb der Schädelbasis liegende weitere Knochenmetastasen auf. Eine durale Infiltration oder eine Meningeosis neoplastica lagen bei je 13 % der Patienten vor. Nach Bestrahlung waren 61 % der Patienten hinsichtlich der auf die Schädelbasismetastase zurückzuführenden Symptome klinisch stabil, bei 22 % hatten sich die Symptome gebessert. Das mediane Gesamtüberleben betrug 8 Monate (Spanne: 0,4–51 Monate). Bei Patienten, die mit einer dosiseskalierten Bestrahlung behandelt wurden, bestand eine längere Überlebenszeit (16,4 Monate vs. 4,7 Monate). Dieser Effekt persistierte auch in der multivariaten Analyse unter Berücksichtigung der Faktoren Karnofsky-Index, Metastasenanzahl, Primärtumor und Bestrahlungsdosis (HR 0,37, p = 0,02).

Diskussion

Schädelbasismetastasen mit Hirnnervenausfällen haben ein vielgestaltiges Bild und oft eine schlechte Prognose. Um potenziell eine Überlebenszeitverbesserung zu erreichen, sind präzise Diagnostik und Therapie Voraussetzung. Prospektive kontrollierte Untersuchungen sind notwendig.

Trans-oral approach for occipital condyle biopsy: Case report and review of literature

Isolated occipital condyle lesions are commonly treated with empirical radiation, with the sole aim of relieving symptoms. Patients rarely undergo surgical biopsy, considering the morbidity associated with open surgery approaches and the importance of surrounding structures limiting the application of computed tomography (CT) scan or fluoroscopic percutaneous needle biopsies. We describe the case of a 66-year-old woman who was admitted on an emergency basis. Her clinical presentation included unilateral occipital headache and ipsilateral hypoglossal nerve palsy. Imaging revealed findings consistent with an isolated right occipital condyle lesion. In order to pursue a tissue diagnosis, essential to dictate medical management accurately, a minimally invasive biopsy of the occipital condyle through the trans-oral route was performed. Combined fluoroscopy, cone-bean CT and angiography allowed safe access to the lesion.

Management of Skull Base Metastases

Autopsy studies suggest that skull base metastases are likely underrecognized in patients with cancer. Patients frequently present with one or a combination of skull base clinical syndromes that manifest as pain or cranial neuropathy. Once a skull base metastasis is suspected, establishing a histologic diagnosis, dedicated imaging, and restaging (if appropriate) are the first steps in management. A multidisciplinary approach should then be used to identify the optimal histology-based treatment strategy, taking into account the burden of systemic disease. Finally, definitive treatment may include one or a combination of surgical management, radiation therapy, or chemotherapy."

"Single-step" resection and cranio-orbital reconstruction for spheno-orbital metastasis with custom made implant. A case report and review of the literature

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Skull Base Metastases need multidisciplinary treatment.

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Surgical decompression has a decisive role in relieving neurological symptoms and improving Quality of Life.

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The virtual planning step consists of a phantom-base procedure with the aid of Stealth Navigation.

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New generations of custom-made PolyMethyl MethAcrylate (PMMA) cranioplasty allow a quick access to complementary therapies.

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Stealth navigation during the surgical step allows a precise tumor resection and drives to an accurate cranial reconstruction.

Introduction and importance

Brain metastasis involving the skull base is a rare complication of malignant tumors. Besides radiotherapy, surgical treatment is a therapeutical option even though it may apply complex technical procedures that may delay complementary therapies. However, in recent days, the innovation of custom-made implants allows treating selected patients with fewer complications and better results.

Case presentation

We describe a single case of a complex fronto-orbital skull base metastasis requiring skull bone reconstruction that we treated with a single-step surgery and custom-made implant. Our procedure consists of two steps: in the first one, we perform a “virtual” craniotomy on a 3D phantom model previously built on a high-resolution bone CT scan. In the second step, the actual surgical procedure, the patient undergoes the resection and reconstruction of the cranial defect with an implant of PMMA custom-made cranioplasty. A three-month clinical and radiological follow-up is reported, which documented the extent of resection and good aesthetic results.

Clinical discussion

In our case, we performed a skull reconstruction of cranio-orbital region with macroscopic gross-total resection of the tumor. Complementary radiotherapy was obtained after one month. Three-month follow-up showed good esthetic results and progression-free disease. A recent review of the literature is provided to discuss different reconstruction techniques.

Conclusion

“Single-Step” resection and custom-made reconstruction is a relatively new technique that could be helpful not only for benign tumors, which remains its main application but also in selected cases of malignant tumors when immediate reconstruction and faster complementary treatments are needed.

Diagnosis of Skull Base Osteomyelitis

Skull base osteomyelitis (SBO) is an infection of the temporal, sphenoid, or occipital bone that can be a challenge to diagnose because of its nonspecific symptoms, long clinical course, and radiologic findings that mimic those of other entities. The authors review this unusual infection on the basis of six proven cases. The diagnosis of SBO should be made according to four points: a high index of clinical suspicion, radiologic evidence of infection, repeated biopsies that are negative for malignancy, and positive results of microbiologic tests. SBO typically manifests clinically in patients with diabetes and recurrent otitis externa; the infection usually extends inferiorly to the compact bone of the infratemporal fossa, affecting the lower cranial nerve foramina. Several image-based techniques should be used to diagnose SBO. CT is the best option for evaluating bone erosion and demineralization, MRI can help delineate the anatomic location and extent of disease, and nuclear imaging is useful for confirming bone infection with high sensitivity. However, the standard diagnostic procedure for SBO is for patients to undergo repeated biopsies to rule out malignancy, with histopathologic signs of infection and detection of microorganisms in the biopsied bone or soft tissue indicating SBO. The ability to diagnose SBO can be increased by identifying patients at risk, recognizing the most important causes and routes of infection, describing the main radiologic findings, and always considering the differential diagnosis. ^©RSNA, 2021.

CyberKnife Radiotherapy for Skull Base Petroclival Metastases Including Dorello's Canal: Report of 10 Cases

Skull base petroclival metastases cause diplopia due to abducens nerve palsy. Diplopia is visually disabling, and skull base metastasis is extremely difficult to treat even with microscopic surgery. However, stereotactic radiotherapy with CyberKnife (Accuray Incorporated, Sunnyvale, California) has been very successful in 10 cases. As the abducens nerve runs through Dorello’s canal in the skull base, the radiation dose and fraction were adjusted to avoid damage to the nerve. Since these metastases are not located inside the brain but in the skull base, contrast magnetic resonance imaging (MRI) combined with fluorodeoxyglucose-positron emission tomography (FDG-PET) was essential to detect the cancers.

Base of Skull Metastatic Adenocarcinoma from the Breast 23 Years after the Primary Diagnosis

Breast cancer metastases to the base of the skull with concomitant infiltration into the paranasal sinuses and nasopharynx are exceptionally rare with only small numbers of reported literatures. Greenberg et al. in 1981 described five clinical syndromes with regards to the base of skull metastases and the clinical presentation of each syndrome related to its anatomical location. Often, metastases to the base of the skull remain asymptomatic until the lesion has increased to a considerable size causing bony destruction and impingement to the surrounding structures. When involving the paranasal sinuses or nasopharynx, the most common presenting symptoms mimic those of rhinosinusitis and, hence, may delay the accurate diagnosis. We are reporting a case of base of skull metastasis from breast carcinoma, 23 years after the primary diagnosis. To the best of our knowledge, our case is the first case to report latent metastasis of more than 20 years.

Unusual skull base metastasis from neuroendocrine tumor: a case report

Background

With increasing treatment options available, neuroendocrine tumor has become a chronic disease and may present later on with atypical manifestation of disease spread once resistant to treatment.

Case presentation

A 74-year-old white British woman undergoing treatment for metastatic well-differentiated neuroendocrine tumor for the past 9 years presented with a brief history of mild frontal headache, and progressive left ptosis and ocular palsy. She had no visual loss, and had neither speech nor motor deficit. At the outset, it was crucial to exclude acute or missed stroke. An urgent magnetic resonance imaging of her head revealed an unusual skull base metastasis extending into the cavernous sinus, with no peritumoral edema. Following discussion at a specialist neuro-oncology meeting and a neuroendocrine tumor multidisciplinary team meeting, she proceeded to have conventional fractionated radiotherapy followed by subsequent palliative chemotherapy.

Conclusions

Intracranial metastasis is rare in patients with neuroendocrine tumor, particularly in those with well-differentiated histology; skull base metastasis is even more uncommon. Management of intracranial metastasis from a rare tumor should always be discussed in a specialist multidisciplinary meeting. Surgery or radiotherapy, including stereotactic radiosurgery, should be considered in skull base metastases. Hormonal abnormalities may occur following radiotherapy to skull base metastases and should be monitored closely in the first few months post treatment.

Single Skull Metastasis 15 Years after Primary Treatment of Prostate Cancer and with Undetectable PSA Levels: A Case Report and Review of the Literature

Prostate cancer is the first cause of skull metastases in men, accounting for 12–18% of all cases. This condition is generally a late event in the course of the disease, involving patients with disseminated lesions. Quite rarely is skull involvement the first and single site of distant recurrence. We report the case of a patient who developed a single skull lesion 15 years after primary treatment of prostate cancer, in the presence of undetectable PSA levels. Pathological assessment performed after resection of the lesion revealed a metastasis from prostate carcinoma. Basing on this experience the appearance of craniofacial pain or a nerve deficit in patients with a history of prostate cancer should alert the clinician to exclude distant recurrence of disease, even in the presence of undetectable PSA levels and even if many years have elapsed since the treatment of the primary tumor. Knowledge of these manifestations will reduce any diagnostic delay and lead to the effective delivery of appropriate treatment.

Plexus and peripheral nerve metastasis

Cancer in the form of solid tumors, leukemia, and lymphoma can infiltrate and metastasize to the peripheral nervous system, including the cranial nerves, nerve roots, cervical, brachial and lumbosacral plexuses, and, rarely, the peripheral nerves. This review discusses the presentation, diagnostic evaluation, and treatment options for metastatic lesions to these components of the peripheral nervous system and is organized based on the anatomic distribution. As skull base metastases (also discussed in Chapter 14) result in cranial neuropathies, these will be covered in detail, as well as cancers that directly infiltrate the cranial nerves. Particular emphasis is placed on the clinical, imaging, and electrodiagnostic features that differentiate neoplastic plexopathies from radiation-induced plexopathies. Neurolymphomatosis, in which malignant lymphocytes invade the cranial nerves, nerve roots, brachial and lumbosacral plexuses, and peripheral nerves, is a rare manifestation of lymphoma and leukemia. Diagnoses of neurolymphomatosis are often missed or delayed given its varied presentations, resulting in poorer outcomes. Thus this disease will also be discussed in depth.

Cavernous sinus syndrome as the first manifestation of metastatic breast disease

Background:

The cavernous sinus is a venous plexus crossed by vital neurovascular structures. Metastases to the region are uncommon and often associated with a headache, facial pain, or progressive neurological deficit in III, IV, and VI cranial nerves. The treatment options are surgery, including endoscopic approach, radiotherapy, radiosurgery, and chemotherapy.

Case Description:

We report the case of a 26-year-old female with cavernous sinus syndrome due to breast cancer metastasis, who was subjected to chemotherapy with complete neurological recovery. A literature review was performed using the databases Bireme, Pubmed, Cochrane, Lilacs and Medline with the keywords: cavernous sinus/metastasis/surgery/radiosurgery for multiple management options review.

Conclusion:

Cavernous sinus metastases are rare, and the cavernous sinus syndrome is rarely the first sign of cancer, especially in young patients. Because the syndrome has multiple causes, the history of rapid progression and atypical image findings can arise suggesting metastatic diseases. As in our case, the image was suggestive of meningioma, however, the clinical presentation and further investigations led us to suspect as a metastatic disease. The therapeutic decision considers clinical and functional status, the extent of primary and metastatic disease, radiological study, tumor histopathology, and biological behavior. Often associated with significant symptoms and disseminated systemic disease, nowadays radiosurgery is the first and less invasive strategy, offering low risk of new deficits, clinical improvement, and good local control. The prognosis depends on early treatment and disease staging because mortality is associated with progression of cancer.

Minimally invasive surgery of the anterior skull base: transorbital approaches

Minimally invasive approaches are becoming increasingly popular to access the anterior skull base. With interdisciplinary cooperation, in particular endonasal endoscopic approaches have seen an impressive expansion of indications over the past decades. The more recently described transorbital approaches represent minimally invasive alternatives with a differing spectrum of access corridors. The purpose of the present paper is to discuss transorbital approaches to the anterior skull base in the light of the current literature. The transorbital approaches allow excellent exposure of areas that are difficult to reach like the anterior and posterior wall of the frontal sinus; working angles may be more favorable and the paranasal sinus system can be preserved while exposing the skull base. Because of their minimal morbidity and the cosmetically excellent results, the transorbital approaches represent an important addition to established endonasal endoscopic and open approaches to the anterior skull base. Their execution requires an interdisciplinary team approach.

Bulbar Paralysis and Facial Paralysis due to Metastatic Hepatocellular Carcinoma: A Case Report and Literature Review

Skull-base metastasis (SBM) from hepatocellular carcinoma (HCC) is extremely rare, and multiple cranial nerve paralysis due to SBM from HCC is also rare. We report a case of bulbar and facial paralysis due to SBM from HCC. A 46-year-old Chinese man presented with a hepatic right lobe lesion that was detected during a routine physical examination. After several failed attempts to treat the primary tumor and bone metastases, neurological examination revealed left VII, IX, X, and XI cranial nerve paralysis. Computed tomography of the skull base subsequently revealed a large mass that had destroyed the left occipital and temporal bones and invaded the adjacent structure. After radiotherapy (27 Gy, 9 fractions), the patient experienced relief from his pain, and the cranial nerve dysfunction regressed. However, the patient ultimately died, due to the tumor's progression. Radiotherapy is usually the best option to relieve pain and achieve regression of cranial nerve dysfunction in cases of SBM from HCC, although early treatment is needed to achieve optimal outcomes. The present case helps expand our understanding regarding this rare metastatic pathway and indicates that improved awareness of SBM in clinical practice can help facilitate timely and appropriate treatment.

Endoscopic Endonasal Management of Metastatic Lesions of the Anterior Skull Base: Case Series and Literature Review

BACKGROUND

The anterior skull base is an uncommon site for brain metastases. A limited number of cases have been reported where a region of the skull base is accessed through an expanded/extended transsphenoidal route. In addition, reports of overall and progression-free survival rates are lacking.

OBJECTIVE

To report progression-free and overall survival rates for skull base metastases treated with aggressive endoscopic endonasal surgery and radiation therapy.

METHODS

We retrospectively review a prospective database of patients at New York Presbyterian Hospital undergoing expanded endoscopic endonasal surgery from 2004 to 2014. From this database, we identified all patients whose final pathology revealed a metastatic lesion in the midline skull base.

RESULTS

Seven hundred forty-nine patients underwent endonasal endoscopic surgery. Final pathology in 12 patients (1.6%) revealed metastasis to the sellar or parasellar region. Tumors were located in the sella, suprasellar cistern, clivus, ethmoid sinuses, sphenoid sinus, cavernous sinus, and craniovertebral junction. Breast and lung cancers were the most common primary diagnoses. Gross total resection was achieved in 41.6% of patients. There were no postoperative cerebrospinal fluid leaks. Adjuvant radiation therapy was used in 92% of cases. Median follow-up was 14 months (range, 1-55). Median progression-free and overall survival were 18 and 16 months, respectively.

CONCLUSIONS

The range of anterior skull base metastatic lesions that can be managed endonasally has increased with the advent of extended endonasal endoscopic surgical approaches. Favorable results can be obtained with this surgical approach as part of the overall management paradigm for patients with skull base metastases.

Fractionated external beam radiotherapy of skull base metastases with cranial nerve involvement

BACKGROUND AND PURPOSE

Skull base metastases frequently appear in a late stage of various tumor entities and cause pain and neurological disorders which strongly impair patient quality of life. This study retrospectively analyzed fractionated external beam radiotherapy (EBRT) as a palliative treatment approach with special respect to neurological outcome, feasibility and acute toxicity.

PATIENTS AND METHODS

A total of 30 patients with skull base metastases and cranial nerve disorders underwent EBRT with a mean total dose of 31.6 Gy. Neurological status was assessed before radiotherapy, during radiotherapy and 2 weeks afterwards categorizing orbital, parasellar, middle fossa, jugular foramen and occipital condyle involvement and associated clinical syndromes. Neurological outcome was scored as persistence of symptoms, partial response, good response and complete remission. Treatment-related toxicity and overall survival were assessed.

RESULTS

Before EBRT 37 skull base involvement syndromes were determined with 4 patients showing more than 1 syndrome. Of the patients 81.1 % responded to radiotherapy with 10.8 % in complete remission, 48.6 % with good response and 21.6 % with partial response. Grade 1 toxicity of the skin occurred in two patients and grade 1 hematological toxicity in 1 patient under concurrent chemoradiotherapy. Median overall survival was 3.9 months with a median follow-up of 45 months.

CONCLUSION

The use of EBRT for skull base metastases with symptomatic involvement of cranial nerves is marked by good therapeutic success in terms of neurological outcome, high feasibility and low toxicity rates. These findings underline EBRT as the standard therapeutic approach in the palliative setting.

What is the Best Route to the Meckel Cave? Anatomical Comparison between the Endoscopic Endonasal Approach and a Lateral Approach

Background Traditionally, a pterional approach is utilized to access the Meckel cave. Depending on the tumor location, extradural dissection of the Gasserian ganglion can be performed. An endoscopic endonasal access could potentially avoid a craniotomy in these cases. Methods We performed an endoscopic endonasal approach as well as a lateral approach to the Meckel cave on six anatomic specimens. To access the Meckel cave endoscopically, a complete sphenoethmoidectomy and maxillary antrostomy followed by a transpterygoid approach was performed. For lateral access, a pterional craniotomy with extradural dissection was performed. Results The endoscopic endonasal approach allowed adequate access to the Gasserian ganglion. All the relevant anatomy was identified without difficulty. Both approaches allowed for a similar exposure, but the endonasal approach avoided brain retraction and improved anteromedial exposure of the Gasserian ganglion. The lateral approach provided improved access posterolaterally and to the superior portion. Conclusion The endoscopic endonasal approach to the Meckel cave is anatomically feasible. The morbidity associated with brain retraction from the open approaches can be avoided. Further understanding of the endoscopic anatomy within this region can facilitate continued advancement in endoscopic endonasal surgery and improvement in the safety and efficacy of these procedures.