Neoplasm

Cerebral neoplasm

一、 glioma

• clinical and pathology: (1) origin: glial cell (2) clinical: the most common primary tumor (3) sorts: (a) astrocytoma, (b) oligodendroglioma (c) ependymoma (d) choroid plexus papilloma etc.

( 一 ) astrocytoma (1) incidence rate: 70% of glioma (2) classification: (a) grade Ⅰ (a): pilocytic astrocytoma (b): subependymal giant cell astrocytoma (b) grade Ⅱ low-grade astrocytoma (c) grade Ⅲ anaplastic astrocytoma (d) grade Ⅳ glioblastoma multiforme

grade Ⅰ: Pilocytic astrocytoma 1. Incidence rate: <1% 2. age: children (peak:7~9 years old ) 3. location: (1) posterior fossa: the most common (2) parenchama of brain 4. pathology: (1) benign (2) with capsule (3) no relapse after ablated 5. types: (1) cystic (2) cystic and solid (3) solid: vary rare 6. Imaging findings: (1) CT (2) MR

CT: (1) shape: round (2) border: clear (3) density: low (4) calcification: 10% (5) hemorrhage: few (6) peripheral edema: slight (7) mass effect: slight or moderate (8) enhancement: solid: yes, cyst: no

Un-enhanced--CT

enhanced--CT

• MR: (1) shape: (2) border: (3) signal:

round clear (a) cystic portion: T1WI: low ,T2WI: high (b) solid portion: isointensity (4) peripheral edema: slight or no (5) enhancement: (a) cystic portion: no (b) solid portion: obviously

Un-enhanced MR

enhanced--MR

grade Ⅱ: low-grade astrocytoma 1. incidence: 25-30% 2. age: young common 3. location: white matter 4. pathology: (1) no necrosis (2) local or diffuse invasive (sometimes) (3) calcification (20% patients ) 5. character: benign 6. Imaging findings: (1) CT (2) MR

• CT: (1) shape: round or oval (2) border: clear (3) density: low or isodensity (4) calcification: 20% (5) hemorrhage: few (6) peripheral edema: slight or no (7) mass effect: slight (8) enhancement: no

• MR: (1) shape: round or oval (2) border: clear (3) signal: T1WI: low , T2WI: high (4) peripheral edema: slight or no (5) enhancement: no

T1WI

T2WI

enhancement

grade Ⅲ: anaplastic astrocytoma 1. incidence: 25-30% 2. age: >40 years old 3. location: white matter 4. pathology: (1) progress quickly (2) necrosis 5. character: malignant 6. imaging findings: (1) CT (2) MR

• CT: (1) shape: irregular (2) border: unclear (3) density: low or mixed (4) peripheral edema: yes (5) mass effect: yes (6) calcification: rare (7) enhancement: obviously or no

(a)

(b)

• un-enhancement: in the right temporal lobe and base ganglia, mixed mass, ill-defined, irregular, peripheral edema, midline configuration displaced (b) enhancement: un-homogeneous

• MR: (1) shape: (2) border: (3) signal:

irregular ill-defined T1WI: low or mixed T2WI: high or mixed (4) peripheral edema: T1WI: low,T2WI: high signal (5) mass effect: notable (6) enhancement: un-homogeneous

Un-enhancement

enhancement

grade Ⅳ: glioblastoma multiforme 1. incidence: 50% 2. age: 50-70 years old 3. location: supratentorial white matter 4. pathology: (1) progress quickly (2) necrosis (3) hemorrhage 5. calcification: rare 6. character: malignant 7. Imaging findings: (1) CT

• CT: (1) shape: irregular (2) border: unclear (3) density: mixed (4) peripheral edema: obvious (5) mass effect: obvious (6) enhancement: flower ring-like or irregular thick wall or wall nodule

(a)

(b)

• un-enhancement: in the left frontal lobe, mass: ill-defined, obvious edema, midline configuration displaced, in addition: necrosis (b) enhancement: flower ring-like , wall nodule, necrosis has no enhancement

MR: (1) shape: irregular (2) border: unclear (3) signal: mixed (4) peripheral edema: obvious (5) mass effect: obvious (6) enhancement: flower ring-like or irregular thick wall or wall nodule

（二） oligodendroglioma 1. incidence: 2. age: 3. location:

4~7% of glioma 30-50 years old (1) supratentorial:85% (2) superficial ： subcortical 4. pathology: (1) cystic change and necrosis (2) hemorrhage (3) types: (a) simple: rare (b) mixed: often 5. calcification: often, 50~80% 6. Imaging findings: (1) CT (2) MR

• CT: (1) shape: irregular (2) border: clear or unclear (3) density: mixed (4) calcification: coarse granular, patchy, strip (5) peripheral edema: mild or moderate (6) mass effect: mild or moderate (7) enhancement: slight or no

enhancement Un-enhancement

• MR: (1) shape: (2) border: (3) signal:

irregular well or ill-defined T1WI: low or mixed T2WI: high or mixed (4) calcification: unclear on MRI (5) peripheral edema: T1WI: low T2WI: high (6) mass effect: mild or moderate (7) enhancement: slight or no

（三） ependymoma 1. incidence: 5% of intracranial tumors 2. age: (1) children and teenagers: very common (2) adults: rare 3. location: (1) : infratentorial (60~70%), 4th ventricle (2): supratentorial (30~40%), lateral ventricle or parenchma 4. pathology: (1) cystic change: common (2) hemorrhage: rare (3) quality: moderate malignant 5. calcification: 50% 6. feature: plasticity (grow into cerebellopontine angle or foramen magnum along the lateral or median aperture) 7. Imaging findings: (1) CT (2) MR

• CT: (1) shape: (2) border: (3) density:

irregular unclear iso- or hypodensity or mixed

(4) calcification: 50% (5) peripheral edema: mild (6) mass effect: moderate (7) enhancement: mild or moderate

• MR: (1) shape: (2) border: (3) signal:

irregular well or ill-defined T1WI: low or mixed T2WI: high or mixed (4) calcification: unclear on MRI (5) enhancement: slight or no

plasticity

（四） choroid plexus papilloma 1. incidence: 0.5% of intracranial tumors, 2~3% of glioma 2. age: (1) children: <5 years old (50~80%) (2) adults: rare 3. location: (1) : children: lateral ventricle (2): adults: 4th ventricle 4. pathology: (1) cystic change and necrosis: rare (2) hemorrhage: rare (3) calcification: rare (4) quality: benign 5. hydrocephalus: (1) the way of cerebrospinal fluid is blocked (2) tumor produce a large quantity of cerebrospinal fluid 6. Imaging findings: (1) CT (2) MR

• CT: (1) shape: irregular (2) border: clear, smooth or lobulated (3) density: homogeneous and iso- or hyperdensity (4) calcification: rare (5) enhancement: obviously

Patient: a 4-year-old girl, headache, enlargement of head

Un-enhancement

enhancement

• MR: (1) shape: (2) border: (3) signal:

irregular well-defined T1WI: iso- or low T2WI: high (4) enhancement: obviously

Un-enhancement

enhancement

二 、 meningioma

Pathology (1) origin: arachnoid cap cell (2) blood supply: rich (3) calcification: common (4) cystic change and necrosis: rare (5) hemorrhage: rare (6) types: according to proliferation activity and invasion (a) typical meningioma (b) atypical meningioma (c) anaplastic or malignant meningioma

• clinical : (1) location: anywhere that arachnoid exits (parasigittal, convexity, sphenoid wing, cerebellopontine angle, and so on.) (2) age: (a) adults: often (b) children: rare (3) gender: female : male = 2:1 (4) clinical: (a) the sencond most common intracranial tumor (b) the most non-glial primary brain tumor (c) the most common intracranial extracerebral tumor

Imaging findings: (a) CT (b) MR

• CT: (1) shape: (2) border: (3) density:

round or semicircle clear, smooth (a) hyperdensity: 75% (b) isodensity: 25% (c) hypodensity: rare (4) calcification: common (5) abnormality of nearby bone (a) hyperostosis: the most common (b) destruction (6) enhancement: obviously and homogeneous

• MR: (1) shape: round or semicircle (2) border: well-defined (3) signal: T1WI: isointensity T2WI: isointensity (notes: if the whole tumor become calcification or fibrosis, it shows hypointenstiy on T1 and T2) (4) peripheral circle hypointenstiy: (a) cerebrospinal fluid (b) dura mater (c) vessel (5) dural tail sign: enhanced crescentic dura extend away from the tumor (6) enhancement: obvious and homogeneous

dura tail sign

abnormality of nearby bone Proliferation and destruction of bone

Unenhancement

enhancement

三、 pituitary adenoma

• Pathology (1) origin: adenohypophysis (2) blood supply: rich (3) calcification: very rare (4) cystic change and necrosis: common (5) hemorrhage: common

• clinical : (1) location: gland of pituitary (2) age: (a) adults: common (b) children: no (3) occur rate: the third most common intracranial tumor (4) type: ① according to size: (a) pituitary macroadenoma (diameter ≧10mm) (b) pituitary microadenoma (diameter <10mm) ② according to function (a) without secretion function (b) with secretion function (prolactinoma, growth hormone adenoma, and so on) (5) clinical manifestations: dependent on the types of tumor (a) prolactinoma: lactation and amenorrhea (b) growth hormone adenoma: acromegaly or gigantism

Imaging findings: (a) CT (b) MR

• Pituitary macroadenoma CT: (1) shape: round (2) border: clear, smooth (3) density: homogeneous or mixed, liquid level (4) calcification: very rare (5) abnormality of sellar turcica (a) sellar turcica: enlargement (b) dorsum sella: thinness or tilt (c) sellar floor : sag (d) nearby bones: absorption (6) enhancement: obviously and homogeneous or ring

• Pituitary macroadenoma MR: (1) shape: (2) border: (3) signal:

round well-defined T1WI: isointensity or mixed T2WI: isointensity or mixed (4) enhancement: obvious and homogeneous or un-

Un-enhancement

Un-enhancement

• Pituitary microadenoma CT: no very helpful

• Pituitary microadenoma MR: (1) direct sign: enhancement: (a) local small round or oval or irregular low signal (b) small ring enhancement (c) delayed scan: high signal > normal pituitary tissue (2) indirect sign: (a) sellae diaphragma asymmetry bulge (b) stalk hypophysial excursion (c) sellar floor sag

Un-enhanced

Enhanced

四、 craniopharyngioma

• Pathology (1) origin: remnants of Rathke,s pouch (2) calcification: common (3) cystic change and necrosis: common (4) hemorrhage: very rare (5) types: (a) cystic : 70~95% (b) cystic and solid (c) solid: rare (6) elements of cystic liquid: (a) cholesterol crystal (b) keratin chipping (c) metahemoglobin

• clinical : (1) location: (a) suprasellar: 70% (b) sellar and suprasellar : 20% (c) sellar: 10% (2) age: (a) children: >50% (b) adults: 40~60 years old (3) incidence: 2~8% of the intracranial tumors (4) clinical manifestation: (a) headache (b) visual impairment, vision defect (c) hydrocephalus (d) diabetes insipidus

Imaging findings: (a) CT (b) MR

• CT: (1) shape: round or similar round (2) border: clear (3) density: hypodensity or mixed, CT value: -40~10HU (notes: CT value>20HU with protein element increase) (4) calcification: (a) incidence: common (children: 90%, adults: 30%) (b) shape: arc-shaped or eggshell-like or patchy (5) abnormality of sellar turcica: usually no change (6) suprasellar cistern: part or whole occluded (7) enhancement: (a) cystic wall: ring enhancement (b) solid portion: obvious enhancement (c) cystic portion: un-enhancement

• MR: (1) shape: round or similar round (2) border: well-defined (3) signal: variety of signals dependent on main components ① cytic change and necrosis: ② cholesterol crystal: ③ keratin chipping: ④ metahemoglobin:

T1WI: low T1WI: high T1WI: isoT1WI: high

T2WI: high T2WI: low T2WI: high T2WI: high

(4) enhancement: cystic wall, mural nodule and solid portion show obvious

Un-enhancement enhancement

五、 acoustic nerve neurilemmoma

• Pathology (1) origin: Schwann cell (2) calcification: rare (3) cystic change and necrosis: common (4) hemorrhage: very rare

• clinical : (1) location: cerebellopontine angle (2) age: (a) adults: common (20~50 years old) (b) children: very rare (3) incidence: 75~80% of the CPA tumors (4) clinical manifestation: (a) tinnitus (b) hearing loss (c) obstructive hydrocephalus

Imaging findings: (a) CT (b) MR

• CT: (1) shape: round or similar round or irregular (2) border: clear (3) density: hypodensity or mixed (4) abnormality of internal auditory canal: enlargement (5) supratentorial ventricle: enlargement (6) enhancement: (a) homogeneous (b) un-homogeneous

Un-enhancement enhancement

Un-enhancement

enhancement

• MR: (1) shape: round or similar round or irregular (2) border: well-defined (3) signal: T1WI: iso- or hypointensity T2WI: iso- or hyperintensity (4) abnormality of internal auditory canal: enlargement (5) supratentorial ventricle: enlargement (6) enhancement: homogeneous or un-homogeneous

六、 medulloblastoma

• Pathology (1) origin: medullary velum embryological cell (2) calcification: rare (10~15%) (3) cystic change and necrosis: common (4) hemorrhage: rare (5) quality: (a) very malignant (b) rapid growth (c) spread along CSF

• clinical : (1) location: midline of cerebellum vermis (2) age: (a) children: common (b) adults: very rare, cerebellar hemisphere (3) incidence: (a) 15~20% of the intracranial tumors (b) 30~40% of the posterior fossa tumors (4) clinical manifestation: (a) headache, vomiting (b) unstable walking (c) obstructive hydrocephalus

Imaging findings: (a) CT (b) MR

• CT: (1) shape: round or similar round or irregular (2) border: clear (3) density: slight hyperdensity or isodensity (4) cystic change: multiple and small (5) calcification: 10~20% (6) hemorrhage: rare (7) supratentorial ventricle: enlargement (8) enhancement: (a) > 90% enhanced (b) degree varies from mild to moderate

• MR: (1) shape: round or similar round or irregular (2) border: well-defined (3) signal: T1WI: iso- or hypointensity T2WI: iso- or hyperintensity or mixed (4) supratentorial ventricle: enlargement (5) enhancement: variable

Adult medulloblatoma

七、 pineal region tumors

1. incidence: <1% of intracranial tumors 2. Types : (a) pinealoma: 8% (b) germinoma: 40% (c) teratoma: 30% (d) meningioma: 20% (e) others: 2%

1. pinealoma • Pathology (1) origin: pineal gland cell (2) calcification: common (3) cystic change and necrosis: rare (4) hemorrhage: rare (5) types: (a) pinealoma: benign (b) pinealoblastoma: malignant

• clinical : (1) location: area of pineal body, rear third ventricle (2) age: (a) children: pinealoblastoma common (b) adults: pinealoma common (3) incidence: <1% of the intracranial tumors (4) clinical manifestation: (a) headache, vomiting (b) obstructive hydrocephalus

Imaging findings: (a) CT (b) MR

• CT: (1) shape: round or oval (2) border: clear (3) density: slight hyperdensity or isodensity (4) calcification: common (5) cystic change: rare (6) hemorrhage: rare (7) posterior third ventricle: enlargement , like cup-shaped mouth (8) enhancement: (a) pinealoma: homogeneous or un(b) pinealoblastoma: un- homogeneous

Case: a 40-year-old man, headache

• MR: (1) shape: (2) border: (3) signal:

round or oval well-defined T1WI: iso- or mixed T2WI: iso- or mixed (4) enhancement: (a) pinealoma: homogeneous or un(b) pinealoblastoma: un- homogeneous

Case: a 42-year-old female, nausea and dizziness for 2 years

2. germinoma

• Pathology (1) origin: germ cell (2) calcification: rare (3) cystic change and necrosis: rare (4) hemorrhage: rare (5) spread along CSF

• clinical : (1) location: (a) area of pineal body, midline (b) suprasellar, (c) basal ganglia (2) age: 10~25 years old common (3) incidence: (a) the most common in pineal region (b) male: >90% (4) feature: sensitive to radiotherapy, disappear (5) clinical manifestation: (a) hydrocephalus (b) sexual precocity

Imaging findings: (a) CT (b) MR

• CT:

(1) shape: similar round or irregular (2) border: clear (3) density: slight hyperdensity or isodensity (4) calcification: rare (5) cystic change: rare (6) hemorrhage: rare (7) posterior third ventricle: enlargement, like cup-shaped mouth (8) enhancement: un- or homogeneous and obviously

Case: a 13-year-old girl, sexual precocity

• MR: (1) shape: (2) border: (3) signal:

similar round or irregular well-defined T1WI: iso- or mixed T2WI: iso- or mixed (4) enhancement: un- or homogeneous and obviously

enhancement

Un-enhancement

3. teratoma

• Pathology (1) origin: three germinal layers (2) calcification: more (3) components: (a) cystic portion (b) solid portion (c) germ layer organization (fat tissue, skeleton, tooth, gland, hair, skin, muscle, and so on.)

• clinical : (1) location: (a) area of pineal body, midline, 50% (b) saddle area: 15% (c) others: 35% (2) age: < 20 years old : 70% (3) incidence: rare, 0.3~0.7% (4) types: (a) benign teratoma (b) malignant teratom (5) clinical manifestation: (a) hydrocephalus (b) sexual precocity

Imaging findings: (a) CT (b) MR

• CT: (1) shape: similar round or lobulated (2) border: clear (3) density: mixed (fat tissue, soft tissue, calcification) (4) calcification: more (5) enhancement: solid portion obviously (On CT typical feature: fat tissue, skeleton, tooth)

• MR: (1) shape: similar round or irregular (2) border: well-defined (3) signal: (a) solid portion: T1WI: isoT2WI: iso(b) cystic portion: T1WI: hypo- T2WI: hyper(c) fat tissue: T1WI: high T2WI: high (d) skeleton or calcificatin: T1WI: low

(4) enhancement: solid portion obviously

T2WI: low

Case: a 1-year-old child, vomitting for a month

Fat saturation

enhancement

八、 metastasis

• Pathology (1) origin: other place tumor (2) hemorrhage: more common (3) cystic change and necrosis: rare (4) types: (a) nodular type (b) diffuse type (c) mixed type

• clinical : (1) location:

(a) brain parenchyma (b) meninges (c) skull (2) age: >50 years old common (3) incidence: 8% (4) types: (a) multiple: common (b) single: rare (5) primary place: (a) lung: the most common, 80% (b) breast cancer: the second most common (6) clinical manifestation: headache, nausea, vomit

1.Imaging findings: (a) CT (b) MR 2. Imaging features: (a) small nodule (b) extensive edema

• CT and MR: (1) shape: round or irregular (2) border: clear (3) density or signal: variable (4) enhancement: (a) nodular (b) ring (c) irregular

1. Direct signs: (1) nodular or mass (2) ring (3) cyst-like (4) diffusely invasive 2. Indirect sign: (1) peripheral edema (2) mass effect: notable

steps of diagnosis of intracranial tumors 1. localization 2. clinical: (a) age (b) gender (c) symptom and sign (d) laboratory examination 3. Imaging findings: CT and MRI 4. qualitation

Saddle area tumors: (1) pituitary adenoma (prolactinoma: lactation and amenorrhea)

(2) craniopharyngioma (3) Rathke cyst (4) germinoma (5) meningioma (6) aneurysm

Differential diagnosis Intra-cerebral

Extra-cerebral

1. border of tumor

unclear

clear

2. abnormality of inner table

normal

abnormality

3. nearby subarachnoid space or cistern

become narrow or occluded

widen

4. cerebral cortex position

displace outwards

displace inwards

acute angle

obtuse angle

tumor

5. angle of contact of tumor and bone

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