Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_6009_Библиотеки_им_академика_М_И_Перельмана.pdf
Osteoblastoma
KEY FACTS
TERMINOLOGY
• Benign tumor that forms osteoid
• Differentiated grossly from osteoid osteoma by larger size
(> 1.5 cm)
IMAGING
• 40% of osteoblastomas occur in spine
• Well-circumscribed, expansile lesion of neural arch
○ Frequent extension into vertebral body
○ Narrow zone of transition, sclerotic rim
• Periosteal inflammatory response of adjacent ribs, pleural
thickening, effusion
• Peritumoral edema (flare phenomenon)
Neoplasms, Cysts, and Other Masses
○ On MR, edema enhances, obscures tumor margins, and
mimics malignancy
TOP DIFFERENTIAL DIAGNOSES
• Osteoid osteoma
• Aneurysmal bone cyst
(Left) Axial graphic shows
expansile, highly vascular
osteoblastoma (OB) ſt arising
in the right lamina and
impinging on the exiting nerve
root. (Right) Axial bone CT in
the same patient shows an
expansile mass ſt containing
thin, irregular bone trabeculae
that is characteristic of OB.
Although cortical
breakthrough is present, the
zone of transition to adjacent
bone is narrow and sclerotic.
• Metastasis
• Osteogenic sarcoma
• Chordoma
• Infection
PATHOLOGY
• Tumor prostaglandins release causes extensive peritumoral
edema
CLINICAL ISSUES
• 90% in 2nd-3rd decades of life
• Dull, localized pain
• Painful scoliosis
• Neurologic symptoms due to compression of cord, nerve
roots
DIAGNOSTIC CHECKLIST
• May be occult on radiographs; consider MR in young
patients with painful scoliosis
270
(Left) Axial T2WI MR shows an
osteoblastoma of L5 with
characteristic heterogeneous
signal intensity. The bony
matrix is low signal. There is
edema in the adjacent
vertebral body. (Right)
Sagittal bone CT shows
expansile lower thoracic OB
extending from the lamina
into the spinal canal. The
lesion is sharply circumscribed
and bilobed, involving 2
adjacent levels.
Aneurysmal Bone Cyst
KEY FACTS
Neoplasms, Cysts, and Other Masses
IMAGING
• 10-30% of aneurysmal bone cysts (ABCs) occur in spine and
sacrum
• Centered in neural arch, extends into vertebral body
• Balloon-like expansile remodeling of bone
○ Thinned, "eggshell" cortex
○ Focal cortical destruction common
• Absent pedicle sign: Expansion of pedicle results in loss of
pedicle contour on AP radiographs
• Contains multiple round cysts with fluid-fluid levels
○ Caused by hemorrhage, blood product sedimentation
• Blood-filled cysts separated by septa of varying thickness
○ Periphery and septa enhance
○ Solid ABC variant enhances diffusely
• Calcified tumor matrix absent
• Narrow, nonsclerotic zone of transition with adjacent bone
• CT best to differentiate from telangiectatic osteogenic
sarcoma
○ Narrow zone of transition in ABC
○ Absence of infiltration into surrounding soft tissues
• MR shows epidural extent, cord compromise
TOP DIFFERENTIAL DIAGNOSES
• Osteoblastoma
• Telangiectatic osteogenic sarcoma
• Metastases
• Giant cell tumor
• Tarlov cyst
PATHOLOGY
• Now considered true neoplasm since cytogenetic
abnormalities found in > 50%
• Translocation between chromosomes 16 and 17
CLINICAL ISSUES
• Young patient with back pain of insidious onset
(Left) Axial graphic shows an
aneurysmal bone cyst with an
expansile, multicystic mass in
the posterior vertebral body
and pedicle extending into the
epidural space. Fluid-fluid
levels are characteristic.
(Right) Anteroposterior
radiograph shows an
aneurysmal bone cyst of T12
with an absent pedicle sign
. The superior and inferior
extent of tumor is shown by
bone destruction , which
involved the vertebral body as
well as the neural arch.
(Left) Axial T2WI MR shows an
aneurysmal bone cyst of T12
with multiple fluid-fluid levels
due to layering blood
products. The zone of
transition to normal bone
is narrow and sclerotic. There
is cortical breakthrough as
well as extension into the
spinal canal compressing
the spinal cord. (Right) Axial
NECT shows an extensive
aneurysmal bone cyst
involving the entire C2 body
with body ſt and posterior
element expansion. The
bony expansion is the typical
soap bubble type with intact
cortical margins.
271
Giant Cell Tumor
KEY FACTS
TERMINOLOGY
• Giant cell tumor (GCT)
• Locally aggressive neoplasm composed of osteoclast-like
giant cells
IMAGING
• 3% of all GCTs occur in spine
• 4% of all GCTs occur in sacrum
• Lytic, expansile lesion of vertebral body or sacrum
• Narrow zone of transition, margin not sclerotic
• Matrix absent but may have residual bone trabeculae
• May have cortical breakthrough
Neoplasms, Cysts, and Other Masses
• Heterogeneous contrast enhancement
• Nonenhancing areas of necrosis often present
• May be associated with aneurysmal bone cyst component
TOP DIFFERENTIAL DIAGNOSES
• Metastasis
• Myeloma
(Left) AP radiograph shows a
giant cell tumor (GCT) st of
the sacrum. Lytic lesions in this
region are difficult to see on
radiographs and may be
mistaken for bowel gas.
Arcuate lines are a useful
landmark. In this case, the S1
& S2 ſt arcuate lines are
visible on the normal right side
but destroyed on the left.
(Right) Axial NECT shows a
nearly complete cortical rim
around a large sacral mass.
There is a small region of
cortical breakthrough ſt &
extension of tumor from the
sacrum into right iliac wing
across the sacroiliac joint .
• Chordoma
• Osteogenic sarcoma
CLINICAL ISSUES
• Back pain of insidious onset, greatest at night
• Locally aggressive: 12-50% recurrence rate
• Curettage alone associated with high rate of recurrence
○ Curettage defect filled with methylmethacrylate or bone
graft
○ Denosumab: Human monoclonal antibody to RANKL
– In one study, 86% of patients had tumor response
DIAGNOSTIC CHECKLIST
• Most likely causes of solitary sacral mass in adult patient are
GCTs, chordoma, and plasmacytoma
• Malignant GCTs rare, difficult to distinguish from typical
GCT
○ Zone of transition usually less well defined
272
(Left) Lateral radiograph
shows a lytic lesion ſt of L1.
The lesion is sharply
demarcated with a
nonsclerotic margin. There is
probable cortical
breakthrough inferiorly .
This constellation of findings is
consistent with GCT and other
intermediate aggressivity
lesions, such as plasmacytoma,
chordoma (rare at this site), or
some metastases. (Right) Axial
CECT in the same patient
shows a heterogeneously
enhancing mass with cortical
breakthrough st.
Osteochondroma
KEY FACTS
Neoplasms, Cysts, and Other Masses
TERMINOLOGY
• Osteochondroma (OC)
• Osteocartilaginous exostosis, exostosis
• Cartilage-capped osseous growth contiguous with parent
bone
IMAGING
• Sessile or pedunculated osseous cauliflower-like lesion
• Continuity of bony cortex and medullary space between
lesion and underlying bone
• May see chondroid calcifications in cartilage cap
• Center follows normal marrow signal on MR
• Cartilage cap of similar intensity to cord on T1WI,
hyperintense on T2WI
TOP DIFFERENTIAL DIAGNOSES
• Chondrosarcoma
• Osteoblastoma
• Aneurysmal bone cyst
• Tumoral calcinosis
• Enthesopathy
PATHOLOGY
• Idiopathic, trauma, perichondrial ring deficiency
• Radiation-induced OC
• Syndromic: Hereditary multiple exostoses (HME)
• Vertebral OC rare; 1-5% of sporadic OC, 1-9% OC in HME
CLINICAL ISSUES
• Often asymptomatic; incidental diagnosis on radiography
• Palpable mass
• Mechanical impingement of joint, muscle
• Cord compression, radiculopathy unusual
• Peak age = 10-30 years
DIAGNOSTIC CHECKLIST
• Multiplicity → consider HME
• Cartilage cap > 1.5 cm in adults raises concern for malignant
transformation (chondrosarcoma)
(Left) Axial graphic of the
cervical spine demonstrates a
typical osteochondroma
(exostosis) ſt protruding into
the spinal canal causing canal
stenosis and cord compression.
(Right) Axial NECT shows a
large osseous excrescence
projecting ventrally from the
right lateral mass of C2 ſt.
There is ossification of the
cartilaginous cap .
(Left) Axial bone CT shows a
pedunculated osseous lesion
ſt extending into the canal
from the right pedicle with
cortical and medullary
continuity. There is resulting
canal stenosis. The right
pedicle and superior facet are
irregularly enlarged due to
the sessile component of the
osteochondroma. (Right) Axial
T2WI FS MR in the same
patient shows the medullary
continuity of the osseous mass
with the right pedicle ſt and a
hyperintense cartilaginous cap
st. The spinal cord is
displaced and compressed.
273
Chondrosarcoma
KEY FACTS
TERMINOLOGY
• Malignant tumor of connective tissue characterized by
formation of cartilage matrix by tumor cells
IMAGING
• Lytic mass with chondroid matrix
○ Higher grade lesions tend to have larger areas without
calcifications
• Lobular morphology often seen
• Enhancing periphery and internal septa
• May penetrate cortex with epidural or paravertebral
extension
• Thoracic most commonly involved spine segment
Neoplasms, Cysts, and Other Masses
○ Both posterior elements and body (45%)
○ Posterior elements (40%)
• Variable size, typically large at presentation
TOP DIFFERENTIAL DIAGNOSES
• Metastases
(Left) Sagittal graphic of the
lumbosacral junction shows a
large soft tissue mass centered
within the sacrum. This tumor
produces bone destruction
with presacral and epidural
extension. (Right) Axial T1WI
C+ MR shows a large vertebral
mass with paraspinal st and
epidural extension. There is
irregular peripheral
enhancement with some
faintly enhancing central
septations ſt.
• Plasmacytoma
• Lymphoma
• Osteosarcoma
• Malignant fibrous histiocytoma
PATHOLOGY
• Lobulated tumor composed of translucent hyaline nodules
(resemble normal cartilage)
• May be primary or secondary
CLINICAL ISSUES
• Palpable mass
• Localized pain, typically long duration of symptoms
• Neurologic symptoms in 45% of vertebral chondrosarcoma
○ Weakness, paresthesias, paralysis
• Age at presentation: 20-90 years; peak: 40-60 years
DIAGNOSTIC CHECKLIST
• Enlarging or painful enchondroma or osteochondroma
suspicious for sarcomatous transformation
274
(Left) Axial unenhanced bone
CT shows a large mass arising
from the neural arch,
containing ringed and stippled
calcifications st, the typical
appearance of a chondroid
tumor matrix. (Right) Left
paravertebral sagittal T2WI in
the same patient shows a
large, lobulated mass st and a
predominately hyperintense
signal with thin, hypointense
signal around the periphery of
the lobules due to
calcification. This is the typical
MR appearance of a chondroid
neoplasm.
Osteosarcoma
KEY FACTS
Neoplasms, Cysts, and Other Masses
TERMINOLOGY
• Sarcoma containing osteoid matrix produced directly by
malignant cells
IMAGING
• Permeative or moth-eaten appearance
• Cortical breakthrough
• Bone sclerosis due to production of immature bone
• Wide zone of transition
• Discontinuous periosteal reaction, usually multilaminar
• Soft tissue mass [fluid-fluid levels seen in telangiectatic
osteogenic sarcoma (OGS)]
TOP DIFFERENTIAL DIAGNOSES
• Sclerotic metastasis
• Osteoblastoma
• Aneurysmal bone cyst
• Chordoma
• Osteomyelitis
• Ewing sarcoma
• Chondrosarcoma
• Lymphoma
• Malignant giant cell tumor
PATHOLOGY
• 4% of all primary OGS occurs in spine and sacrum
• Majority of OGS are of unknown etiology = primary OGS
• Association with retinoblastoma (Rb gene mutation)
CLINICAL ISSUES
• Insidious onset of back pain, greatest at night
• Neurologic symptoms including radicular pain, weakness
• 3% of 10-year survivors of all OGS develop 2nd malignancy
DIAGNOSTIC CHECKLIST
• CT scan best method for evaluation of tumor matrix, zone
of transition
• All telangiectatic OGS are lytic on radiographs and CT but
not all lytic OGS are telangiectatic
(Left) Axial graphic shows
secondary osteosarcoma
arising in a Pagetic vertebral
body, destroying the cortex
and invading adjacent soft
tissues. The soft tissue mass in
osteosarcoma usually contains
ossification. (Right) Axial CECT
shows a very aggressiveappearing soft tissue mass ſt
that both produces a bony
matrix and has areas of bone
destruction st. There is a
large epidural soft tissue
component with cord
compression .
(Left) Axial T2 FS MR shows a
large soft tissue mass ſt,
which has a relatively low T2
signal that is consistent with a
highly cellular tumor. The
mass has epidural extension
with the cord displaced to the
left . The right vertebral
artery is encased by tumor st.
(Right) Postcontrast T1W MR
shows diffuse enhancement of
the mass with prevertebral ſt
and paravertebral extension
as well as extensive epidural
extension and cord
compression.
275
Chordoma
KEY FACTS
TERMINOLOGY
• Malignant tumor arising from notochord remnants
IMAGING
• Sacrococcygeal > sphenooccipital > mobile spine
• Osseous destruction with disproportionately large soft
tissue mass
• Circumscribed, scalloped, or sclerotic bony margins
• Amorphous intratumoral calcifications
• Hyperintense to disc on T2WI with multiple septa
• May extend into disc space, involve 2 or more adjacent
vertebrae
Neoplasms, Cysts, and Other Masses
TOP DIFFERENTIAL DIAGNOSES
• Chondrosarcoma
• Giant cell tumor
• Metastases
• Plasmacytoma
(Left) Sagittal graphic of the
cervical spine shows an
extradural soft tissue mass
with the epicenter in the
posterior aspect of the C2
body causing bone destruction
and epidural extension with
cord compression. (Right)
Sagittal T2WI MR shows a
hyperintense mass involving
the C3 body with extensive
epidural extension and cord
compression.
PATHOLOGY
• Lobulated, soft, grayish gelatinous (myxoid) mass
• Areas of calcification and hemorrhage
CLINICAL ISSUES
• Skull base
○ Diplopia (CNV2 palsy, most common)
○ Headaches
○ Facial pain
• Mobile spine: Cord compression, radiculopathy (50%)
• Sacral: Altered sacrogluteal sensation
• Symptoms tend to be longstanding (4-24 months)
• Recurrence common
• 5-year survival: 50-68%; 10-year survival: 28-40%
DIAGNOSTIC CHECKLIST
• High signal intensity mass on T2WI with septations, little
enhancement is chordoma or chondrosarcoma
276
(Left) Sagittal T2WI show a
large, well-defined
hyperintense soft tissue mass
engulfing the distal sacrum
and coccyx with extension into
the presacral space and dorsal
soft tissues st. (Right) Sagittal
T2WI FS MR shows a posterior
mediastinal mass with
involvement of 4 adjacent
thoracic vertebral bodies. The
mass is hyperintense with fine
septations st. There is a
pathologic compression
fracture of the top vertebra
with ventral epidural tumor
. Note the scalloped
anterior margins ſt.
Ewing Sarcoma
KEY FACTS
Neoplasms, Cysts, and Other Masses
TERMINOLOGY
• Ewing sarcoma family of tumors
• Aggressive childhood cancer, which includes Ewing
sarcoma, Askin tumor, and peripheral primitive
neuroectodermal tumor
IMAGING
• Spine: 5% of all Ewing tumors
○ Sacrum most common spinal site
○ Spreads along peripheral nerves
• May originate in epidural or paraspinous soft tissues
• Permeative/moth-eaten bone destruction
○ 5% sclerotic (represents host reaction, not tumor matrix)
○ Areas of central necrosis common
○ "Percolates" through tiny perforations in cortex
• Lower signal intensity than disc or muscle on T1WI
○ May be isointense to red marrow on T2WI
○ Intermediate to high signal intensity on STIR
• MR best shows involvement of adjacent bones and soft
tissues, which can be underestimated on CT scan
○ Heterogeneous enhancement with gadolinium
• CT useful to confirm absence of tumor matrix, distinguish
from osteogenic sarcoma
TOP DIFFERENTIAL DIAGNOSES
• Primitive neuroectodermal tumor
• Langerhans cell histiocytosis
• Osteosarcoma
• Metastatic neuroblastoma
• Osteomyelitis
CLINICAL ISSUES
• 90% of all Ewing sarcoma patients present before 20 years
of age
• Fever, leukocytosis, elevated ESR (simulating osteomyelitis)
• Spine and sacral lesions often present in older patients than
peripheral Ewing sarcoma
(Left) Sagittal graphic shows a
vertebral body replaced by
Ewing sarcoma resulting in
mild collapse. Tumor extends
into adjacent soft tissues
through small perforations in
the bone cortex. (Right) Axial
CECT shows a large paraspinal
soft tissue mass of Ewing
sarcoma engulfing the left
psoas muscle ſt with
extension into the dorsal
musculature , destruction
of left side of lumbar body ,
and epidural extension st.
(Left) Axial T2WI MR shows
Ewing sarcoma involving the
paraspinal muscles ſt and
extending into the epidural
space st, compressing and
displacing the thecal sac to
the right. Infiltration of the
vertebral body is poorly
defined on this sequence.
(Right) Axial T1WI C+ MR
shows diffuse heterogeneous
enhancement of the tumor
involving the left side of
lumbar body , epidural
space ſt, and paravertebral
and dorsal muscles.
277
Lymphoma
KEY FACTS
TERMINOLOGY
• Lymphoreticular neoplasms with myriad of specific diseases
and cellular differentiation
IMAGING
• Multiple types with variable imaging manifestations
• Epidural lymphoma: Thoracic > lumbar > cervical
○ Enhancing epidural mass ± vertebral involvement
• Osseous lymphoma: Long bones > spine
○ Bone destruction (ivory vertebra, rare), vertebra plana
• Lymphomatous leptomeningitis
○ Smooth/nodular pial enhancement
Neoplasms, Cysts, and Other Masses
• Intramedullary lymphoma: Cervical > thoracic > lumbar
○ Poorly defined, enhancing mass
• Secondary > primary involvement
• Extradural > intradural > intramedullary
• FDG PET useful for staging, monitoring treatment
response, predicting treatment outcomes, and risk
stratifying lymphoma patients
(Left) Sagittal T2WI MR
demonstrates a discrete
hypointense mass in the
posterior epidural space with a
cap of epidural fat st. The
spinal cord is displaced
anteriorly ſt. Lymphoma is
the most common malignancy
of the epidural space. (Right)
Sagittal T2WI MR (left) shows
an amorphous hypointense
tumor mass insinuating along
the cauda equina ſt. Sagittal
T1WI C+ MR (right) reveals
enhancing lymphoma within
the leptomeninges
surrounding the distal conus
and involving the nerve roots
diffusely .
PATHOLOGY
• Non-Hodgkin lymphoma (NHL) > > Hodgkin disease (HD);
80-90% are B cell
○ CNS lymphoma > 85% NHL (B cell > > > T cell)
• CNS lymphoma may be primary or secondary
(hematogenous or direct geographic extension)
CLINICAL ISSUES
• Most common presenting symptom = back pain
• Intramedullary = myelopathy (weakness, numbness)
• Cord compression occurs in up to 5-10% of systemic
lymphomas
• Generally poor prognosis for CNS lymphoma
• Markedly sensitive to chemotherapy/XRT
• Depressed humoral and cell-mediated immunity leads to
opportunistic infections
• Treatment: XRT ± chemotherapy (markedly sensitive to
chemotherapy/XRT); ± surgery
278
(Left) Coronal PET (left) shows
FDG uptake in the left cervical
lymph node mass ſt that was
clinically evident. PET/CT
fused image (right) shows
abnormal activity at T11 .
This is an example of osseous
metastases from cervical
Hodgkin lymphoma primary
tumor. (Right) Sagittal CT
(left) demonstrates a
pathologic compression
fracture of a midthoracic
vertebral body ſt. Sagittal
T1WI C+ MR (right) confirms
abnormal marrow
enhancement st and a ventral
paraspinal mass .
Leukemia
KEY FACTS
Neoplasms, Cysts, and Other Masses
TERMINOLOGY
• Acute or chronic myeloid or lymphoid white blood cell
neoplasia with spinal involvement as component of
systemic disease
IMAGING
• Radiographs/CT
○ Diffuse osteopenia with multiple vertebral fractures ±
lytic spine lesions
○ Variable enhancing isodense soft tissue mass with
adjacent bone destruction
• MR
○ T1WI: Hypointense marrow and focal tumor masses
○ T2WI: Hyperintense marrow ± focal vertebral mass, cord
signal abnormality
○ T1WI C+: Abnormal enhancement of marrow, focal
lesion, or leptomeninges
TOP DIFFERENTIAL DIAGNOSES
• Metastases
• Lymphoma
• Ewing sarcoma
• Langerhans cell histiocytosis
CLINICAL ISSUES
• Localized or diffuse bone pain
• Symptomatic patients present with fever, ↑ ESR,
hepatosplenomegaly, lymphadenopathy, joint effusions,
petechial and retinal hemorrhage, anemia, frequent
infections
DIAGNOSTIC CHECKLIST
• Marrow infiltration in child with osteoporosis raises
suspicion for leukemia
• Consider leukemia in patient with unexplained compression
fractures
(Left) Sagittal T1WI MR (left)
and T2WI MR (right) of the
cervical spine demonstrate
diffuse abnormal hypointense
signal intensity within the
vertebra. Signal intensity is
lower than the adjacent disc
spaces. (Right) Sagittal T1WI
MR (left) and T2WI MR (right)
of the lumbar spine exhibit
diffuse abnormal hypointense
signal intensity within the
vertebra as compared to the
adjacent disc spaces. The
signal abnormality may be a
combination of tumor marrow
infiltration and hyperplastic
marrow secondary to anemia.
(Left) Coronal planar bone
scan of the pelvis reveals
abnormal increased uptake
within the right sacral ala ſt
in this case of focal leukemic
metastasis to the axial
skeleton. Bone scan may
underestimate disease extent,
especially in absence of
significant cortical
destruction. (Right) Axial T1WI
MR in the same patient
clarifies the right sacral alar
metastatic lesion ſt. There is
no definite cortical
breakthrough.
279