Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Youmans,Neurological surgery Chapter 148 Skull Tumors
Osborn,Expert ddx in brain&spine
Skull tumors
Outline
OsteomaHemangiomaDermoid and
epidermoid tumors
Chondroma (osteochondroma)MeningiomaAneurysmal bone
cyst
Malignant tumorsBone metastases to the skullChondrosarcomaOsteogenic sarcomaFibrosarcoma
Benign tumorsNon-neoplastic skull lesion
Paget's disease of the skull
Langerhans Cell Histiocytosis
(Histiocytosis X)Fibrous dysplasiaHyperostosis
frontalis internaSinus pericranii
Benign tumorsOsteomaHemangiomaDermoid and epidermoid tumorsChondroma(osteochondroma)MeningiomaAneurysmal bone cyst
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
OsteomaThe most common primary bone tumor of
the calvariaBenign,slow-growing lesionsOccur commonly in the cranial vault,
mastoid and paranasalair sinuses, and the mandible
• Common in females, highest incidence is in 6th decade
• Pathology : Consists of osteoid tissue within osteoblastic tissue, surrounded by reactive bone Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
OsteomaSkull x-ray
Round, sclerotic, well demarcated, homogeneous dense projection.
Usually arise from outer table of skull (inner table less common).
May be compact or spongy(spongy osteoma may be radiolucent)
Unlike meningiomas, diploe are preserved and vascular channels are not increased.
Treatment Asymptomatic lesions may simply be followed.Surgery may be considered for cosmetic reasons,
or if pressure on adjacent tissues produces discomfort.
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Osborn,Expert ddx in brain&spine
7% of skull tumorsTwo types: cavernous (most common) and
capillary(rare)
X-rayCharacteristically shows a circular lucency
with honeycomb or trabecular pattern (50% of cases) or radial trabeculations producing a sunburst pattern (11% of cases)
Sclerotic margins are evident in only ... 33%.CT: hypodense lesion with sclerotic spaced
trabeculations. NonenhancingBone scan: typically hot.
Hemangioma
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
HemangiomaTreatment
Accessible lesions may be cured by en bloc excision or curettage.
The gross appearances of a hard, blue-domed mass beneath the pericranium.
Radiation may be considered for inaccessible tumors
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Osborn,Expert ddx in brain&spine
RareUsually midlineArise within the diploe and expand both
inner and outer tablesThese benign lesions may involve
underlying dural venous structures or brain
Dermoid and epidermoid tumor
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Dermoid and epidermoid tumorX-ray
Osteolytic lesions have well-defined, sclerotic margins
CT : hypodense (keratin contains fats), non-enhancing
MRI : like CSF, they are low intensity on T1 WI and high signal on T2WI, but unlike CSF they are high signal on DWI MRI
TreatmentSurgicalSearch must be made for a tract leading to
the intracranial cavity which must be followed if foundGreenberg,Handbook of neurosurgery 21.4 Skull Tumors
Osborn,Expert ddx in brain&spine
Chondroma(Osteochondroma)Arise form ectopic hyaline cartilaginous rest
trapped within suture lineCommon : skull base,anterior to pon ,sphenoid
bone, boardering of foramen lacerum
CT Well-demarcated, off midline, lobulated, contrast-
enhancing, dense mass contiginous with the underlying bone and marked by popcorn calcification
MRIThin cartilaginous cap overlying the dense osseous
core
Youmans,Neurological surgery Chapter 148 Skull Tumors
Chondroma(Osteochondroma)Treatment
Complete resection,including cartilaginous capsule
Youmans,Neurological surgery Chapter 148 Skull Tumors
MeningiomaIntraosseous(intradiploic) meningioma are
uncommonPrimary intraosseous meningiomas do not
involve the inner or outer tables of the skull or the dura
“ectopic meningiomas” or “primary extradural meningiomas”
Arise from rests of arachnoid cap cells trapped within sutures at birth and during molding of the head
Youmans,Neurological surgery Chapter 148 Skull Tumors
MeningiomaPlain radiograph and CT
Hyperostosis(some are lytic or both lytic and sclerotic)Expansion of the diploë, with the inner and outer
tables of the skull separated and thinned over the biconvex mass
MRITW1 : hypointense, TW2 : hyperintenseHomogeneous contrast enhancement on both CT and
MRI
Treatment En bloc resection with margin
Youmans,Neurological surgery Chapter 148 Skull Tumors
Osborn,Expert ddx in brain&spine
Aneurysmal bone cystRareSecondary to trauma to be caused by a
circulatory disturbance resulting in venous hypertension and venous pooling within the bone
A typical finding : local swelling and tenderness of a few month duration
Gross : vascular channel that give them spongy-like appearance
Histologic : communicating pools of venous blood without endothelium in a thin matrix of fibro-osseous strands along with frequent multinucleate giant cells.Youmans,Neurological surgery Chapter 148 Skull Tumors
Aneurysmal bone cystImaging
LyticLoculated lesion with fluid-fluid levels
caused by layering of blood products within internal cavities
The lesion typically begins in the diploë, and expansion or “blowout” of the inner and outer cortices
TreatmentGross total resection
Youmans,Neurological surgery Chapter 148 Skull Tumors
Malignant tumorsBone metastases to the skull
1. prostate2. breast3. lung4. kidney5. thyroid6. lymphoma7. multiple myeloma/plasmacytoma
ChondrosarcomaOsteogenic sarcomaFibrosarcoma
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Bone metastasis to skullMost common : breast, lung, and prostateUncommon : renal and thyroid carcinoma Cranila vault more than skull base
RadiographicLytic lesion except prostate cause sclerotic
lesionMRI : T1W : hypointense with variable T2W
characteristic and variable contrast enhancement
Radionuclide bone scanning : sensitive method for detecting skull metastasis
Youmans,Neurological surgery Chapter 148 Skull Tumors
Bone metastasis to skullCSF
Helpful in suspected metastasis to the skull base
If CSF is normal, metastasis is more likely than infection to be the cause of multiple cranial neuropathies
A CSF study may also reveal the presence of meningeal carcinomatosis
Youmans,Neurological surgery Chapter 148 Skull Tumors
Bone metastasis to skullTreatment
Patients with skull metastases are frequently at an advanced stage of their primary disease and often asymptomatic : Surgery may not be required for diagnostic or even therapeutic purposes
Symptomatic or palpable skull mass may be the first sign of the underlying cancer : surgical resection may be helpful or FNA in multiple or too indolent to need resection
Youmans,Neurological surgery Chapter 148 Skull Tumors
Osborn,Expert ddx in brain&spine
Osborn,Expert ddx in brain&spine
ChondrosarcomaRare,malignant neoplasm of cartilageFound away from midline with cranial
neuropathies(particularly abducen neuropathy)
Skull : painless expanding massSubtype
Myxoid(conventional low grade) most common
DedifferentiatedMesenchymal
Pathologyhypercellular with hyperchromatic and
pleomorphic nucleiYoumans,Neurological surgery Chapter 148 Skull Tumors
ChondrosarcomaCT
Calcifications and ossifications within the tumor mass
MRILobulated lesions that appear isointense to
hypointense on T1-weighted images and hyperintense on T2-weighted images
Show heterogeneous contrast enhancement
TreatmentSurgical resection with adjuvant therapy
Youmans,Neurological surgery Chapter 148 Skull Tumors
Osborn,Expert ddx in brain&spine
Osteogenic sarcomaMost common malignanat tumor in bone
but it is relatively rare in skullCranial vault than skull baseSecondary to radiationPatients with tumors attaining large size or
involving the skull base may complain of local tenderness, headaches, proptosis, ophthalmoplegia, facial weakness, decreasedhearing ability, or tinnitus
The alkaline phosphatase level may be a useful diagnostic test
Youmans,Neurological surgery Chapter 148 Skull Tumors
Osteogenic sarcomaPathology
Sarcomatous spindle cell stroma with an associated osseous component
CTBony destruction, cortical expansion, and
a “sunburst” periosteal reactionDemonstrate areas of irregular calcification,
as well as low-attenuation areas representing necrosis
MRIheterogeneous signal on both T1- and T2-
weightedTreatment
Gross total resectionYoumans,Neurological surgery Chapter 148 Skull Tumors
FibrosarcomaRareMay arise from degeneration of a
preexisting lesion such as a fibroma from Paget’s disease or it may occur after radiation treatment
Typically indolent, asymptomatic massesType : low grade (most differentiated),
moderately differentiated, and poorly differentiated
Pathology interlaced bundles of spindle cells and
collagen fibers in a “herringbone” patternYoumans,Neurological surgery Chapter 148 Skull Tumors
FibrosarcomaRadiographic
Lytic lesion with cortical destruction or expansion, or both, and soft tissue extension
Radiolucent
TreatmentEn bloc resection
Youmans,Neurological surgery Chapter 148 Skull Tumors
Non-neoplastic skull lesionPaget's disease of the skullLangerhans Cell Histiocytosis(Histiocytosis
X)Fibrous dysplasiaHyperostosis frontalis internaSinus pericranii
Youmans,Neurological surgery Chapter 148 Skull Tumors
Paget’s disease of the skull(Osteitis Deformans)Disorder characterized by the uncoupling of
bone formation and resorption, with resultant bone thickening and weakening
ClinicalHeadache, cranial neuropathy, EDH fron trauma
CTAreas of sclerosis mix with the preexisting lytic
areas, and a mottled “cotton wool” appearance develops
MRImixed intensity
Youmans,Neurological surgery Chapter 148 Skull Tumors
Paget’s disease of the skull(Osteitis Deformans)The most common types of sarcomatous
degeneration are to osteosarcoma (50% to 60% of instances) and fibrosarcoma (20% to 25% of instances)
TreatmentMedical : bisphosphonates or calcitonin is the
first line
Youmans,Neurological surgery Chapter 148 Skull Tumors
Paget’s disease Fibrous dysplasia
Symmetrical Unilateral
Thickening of inner cortex
Cortical destruction
Cotton wool Groud grass apperance
Older thane fibrous dysplasia
Involve orbit,paranasal sinus, sphenoid bone
Paget’s disease of the skull(Osteitis Deformans)
Osborn,Expert ddx in brain&spine
Paget’s disease of the skull(Osteitis Deformans)
Osborn,Expert ddx in brain&spine
Fibrous dysplasiaBenign condition in which normal bone is
replaced by fibrous connective tissueMost common : rib or craniofacial bone esp
maxillaPattern
Monostotic: most common Polyostotic: 25% with this form have> 50% of
the skeleton involved with associated fractures and skeletal deformities
as part of McCune-Albright syndromeAutonomous endocrine hormone excess, such as in
precocious pubertyPolyostotic fibrous dysplasiaUnilateral café au lait spots
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Fibrous dysplasiaClinical
incidental findinglocal pain and swelling or deformity may predispose to pathologic fractures when they
occur in long bones cranial nerve involvementseizures serum alkaline phosphatase is elevated in about
33%, calcium levels are normal darkened hair pigmentation overlying skull lesions spontaneous scalp hemorrhages rarely associated with Cushing's syndrome
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Fibrous dysplasiaGroud glass appearance on x-ray due to
the thin spicules of woven bone
TreatmentNo cure for fibrous dysplasiaLocal procedures (mostly orthopedic) are
used for deformities or bone pain that is refractory to other treatment
Neurosurgical involvement may be required for skull lesions producing refractory pain or neurologic symptoms
Calcitonin may be used for widespread lesions with bone pain and/or high serum alkaline phosphatase levels
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Fibrous dysplasia
Osborn,Expert ddx in brain&spine
Fibrous dysplasia
Osborn,Expert ddx in brain&spine
Langerhans cell Histiocytosis(Histiocytosis X)Group of related disorders of abnormal
uncontrolled histiocyte proliferation: Eosinophilic granulomaHand-Schüller-Christian diseaseAbt-Letterer-Siwe diseaseHashimoto-Pritzker disease
Predominantly occurs in children and adolescents, with the mean age at incidence being 12 years
ClinicalSolitary mass with localized pain
Youmans,Neurological surgery Chapter 148 Skull Tumors
Langerhans cell Histiocytosis(Histiocytosis X)Pathology
Clonal proliferation of S-100–positive histiocytic cells in clusters mixed with inflammatory cells, which are predominantly eosinophils.
CD1a antigen EM : racquet-shaped Birbeck’s granules
X-rayClassic punched-out lytic border without a
sclerotic boarderBevel appearance : bony destruction outer
table than inner tableExtraosseous contrast-enhancing soft tissue
mass
Youmans,Neurological surgery Chapter 148 Skull Tumors
Langerhans cell Histiocytosis(Histiocytosis X)Treatment
surgery radiation therapy chemotherapyimmunotherapy
Youmans,Neurological surgery Chapter 148 Skull Tumors
Langerhans cell Histiocytosis(Histiocytosis X)
Osborn,Expert ddx in brain&spine
Hyperostosis Frontalis InternaBenign irregular nodular thickening of the
inner table of the frontal bone that is almost always bilateral
More common in womenClinical
Incidental finding, headache, cranial defectX-ray
Thickening of the frontal bone with characteristic sparing of the midline
TreatmentRemoval of thickening bone
Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Hyperostosis Frontalis InternaMetabolic craniopathy
Morgagni's syndrome (AKA Morgagni-Stewart-Morel syndrome)headache, obesity, virilism and neuropsychiatric
disorders (including mental retardation) Endocrinologic abnormalities
Acromegalyhyperprolactinemia
Metabolichyperphosphatemia obesity diffuse idiopathic skeletal hyperostosis (DISH
Diffuse idiopathic skeletal hyperostosis (DISH) Greenberg,Handbook of neurosurgery 21.4 Skull Tumors
Hyperostosis Frontalis Interna
Sinus pericraniiAbnormal collection of veins adherent to
the outer table of the skull in communication with the intracranial venous sinuses via dilated diploic and emissary veins of the skull
Cause : congenital, spontaneous, traumaLocated in midlineThe lesion is nonpulsatile, expands with a
Valsalva maneuver or while the patient is supine, and decreases with head elevation or direct compression
Histology : a tangle of nonmuscular venous vessel Youmans,Neurological surgery Chapter 148 Skull Tumors
Sinus pericraniiX-ray
Radiolucent due to skull defectCT
Extraosseous soft tissue mass, as well as an emissary channel through the skull, with smooth erosion of the bone’s outer table
CT with contrast show venous fillingMRI
Hypointense on T1 and hyperintense on T2Treatment
Progressive or symptomatic lesionSurgical resection
Sinus pericranii
Top Related