DR.ZEENAT NASEERUDDIN
M.D PATHOLOGY
LECTURE 48
BONE FORMING TUMORS
• OBJECTIVES
• a.Enlist and classify common types of bone tumors.
• b.Discuss their epidemiology.
• c.Describe their morphology and location.
• d.Describe their clinical features and course.
Bone tumors
• Bone tumors are classified into:
• Primary bone tumors
• Secondary bone tumors ( Metastasis)
• Most are classified according to the normal cell of origin
and apparent pattern of differentiation
Bone tumors
• Bone-forming tumors
• Cartilage-forming tumors
• Miscellaneous tumors
• Hematopoietic tumors
• Fibrous tumors
Primary Bone Tumors
Bone-Forming tumors
•
Osteoma
•
Osteoid osteoma and
Osteoblastoma
•
Osteosarcoma
Cartilage-Forming tumors
•
Chondroma
(Enchondroma)
•
Osteochondroma
•
Chondrosarcoma
Miscellaneous tumors
−
Ewing’s sarcoma
•
Giant cell tumor of
bone
Bone tumors:
Etiology ???
Although the cause of most bone tumors is unknown.
 Genetic alterations e.g. bone sarcomas in the Li-Fraumeni and
hereditary retinoblastoma which are linked to mutations in p53 and
Rb genes.





Bone infarcts
Chronic osteomyelitis
Paget’s disease
Radiation and
Metal prostheses are also associated with increased incidence of
bone neoplasia.
Diagnosis of Bone Tumors:
1.
Age of patient
2.
Location of tumor
3.
Radiological appearance
4.
Histological features
• Bone-Forming
Tumors
Osteoma
• Osteoma are benign lesions of bone that in many cases
represent developmental aberrations or reactive growths
rather than true neoplasms.
• Site;
• Age;
Gross:
• Histology:
•
Osteoma
• Small bosselated benign tumor.
• Usually solitary and detected in the middle age.
• Multiple in the setting of Gardner syndrome.
• Do not transform into osteosarcoma.
Osteoid
Osteoma
• Signs/Symptoms:
• Pain, characteristically more intense at night, relieved by
NSAID (PG-E) and eliminated by excision
• Vertebral lesions may cause scoliosis
• Age:
• 10-30 years
• Sex:
• M > F (2:1)
• Anatomic Distribution:
• Nearly every location, most frequent in femur, tibia, humerus,
bones of hands and feet, vertebrae and fibula
• Over 50% of cases in femur or tibia
• Metaphysis of long bones
• By definition less than 2 cm in diameter.
Central radiolucent nidus with or without a radiodense center;
surrounded by thickened sclerotic bone
Central hemorrhagic nidus
surrounded by dense rim of
sclerotic bone
Nidus contains interlacing
network of osteoid and bony
trabeculae with variable amount
of mineralization, lying in
vascular fibrous tissue
Osteoid Osteoma
• Ancillary Testing:
• N/A
• Prognosis/Treatment:
• Surgical excision is treatment of choice
• Recurrence unlikely with complete excision
Osteoblastoma (Giant Osteoid Osteoma)
• Signs/Symptoms:
• Pain
• Gait disturbances
• Age:
• 80% of patients < 30 years
• Sex:
• M >> F (3:1)
• Anatomic Distribution:
• Predilection for vertebral column
• Metaphysis of long bones
Osteoblastoma (Giant Osteoid Osteoma)
• Radiographic Findings:
• Similar to osteoid osteoma, though much larger (up to 11.0
cm)
• Gross and Microscopic Findings:
• Similar to osteoid osteoma, though much larger nidus
• Ancillary Testing:
• N/A
• Prognosis/Treatment:
• Curettage followed by bone grafting
• If incompletely removed, tumor may recur
• Malignant change to osteosarcoma has been rarely reported
Osteosarcoma
• Osteosarcoma is a bone-producing malignant
mesenchymal tumor .
Osteosarcoma
• Incidence:
• Age:
• Sex:
• Site :
Osteogenic Sarcoma (Osteosarcoma)
• Most frequent primary malignant bone tumor
• Malignant cells must produce osteoid
• Most tumors arise de novo (primary), though
others arise in the setting of:
• Paget’s disease
• Previous RT
• Previous chemo (especially alkylating agents)
• Fibrous dysplasia
• Osteochondromatosis
• Chondromatosis
• Chronic osteomyelitis
Osteogenic Sarcoma (Osteosarcoma)
• Signs/Symptoms:
• Pain and swelling
• Pathologic fracture is uncommon
• Age:
• Bi-modal age group
• Peak in 2nd decade with gradual decrease thereafter.
• Sex:
• M>F
• Anatomic Distribution:
• 50% arise around the knee
• Metaphysis of long bones
Osteosarcoma
Distribution
Osteosarcoma
Radiograph
Osteogenic Sarcoma
Morphology:
• Most commonly involves metaphysis of long
bones.
• Gross features: Big bulky tumors, grey white
often containing areas of hemorrhage and cystic
degeneration.
• Micro: Pleomorphic tumor cells with large hyper
chromatic nuclei ,mitotic figures. Formation of
pink homogenous bone is the most characteristic
feature of osteogenic sarcoma
Osteosarcoma
Gross features
Bone-Forming tumors;
Tumor Type
Locations
Age
Morphology
Osteoma
Facial bones, skull
40-50
Exophytic growths
attached to bone
surface; histologically
resemble normal bon
Osteoid osteoma
Metaphysis of femur
and tibia
10-20
Cortical tumors,
characterized by
pain; histologically
interlacing trabeculae
of woven bone
Osteoblastoma
Vertebral column
10-20
vertebral processes;
histologically similar
to osteoid osteoma
Primary
Metaphysis of distal
femur, proximal tibia,
and humerus
10-20
Grow outward, lifting
periosteum, and
inward to the
medullary cavity;
microscopically
malignant cells form
osteoid.
Femur, humerus,
pelvis
>40
Complications of
polyostotic Paget
disease;
histologically similar
to primary
osteosarcoma
BENIGN
MALIGNANT
osteosarcoma
Secondary
osteosarcoma
An 11-year-old male was seen in consultation for an increasingly painful distal
femoral lesion associated with a soft tissue mass.
Plain radiograph shows an ill-defined destructive
tumor in the distal femur. Fluffy radio-dense
infiltrates represent malignant tumor osteoid.
Biopsy material shows two major
components of this neoplasm: highly
pleomorphic cells and haphazard
deposits of osteoid. Note that the
malignant cells fill the spaces between
osteoid deposits. Lace-like osteoid
deposition is very characteristic of this
neoplasm.
A 16-year-old boy was seen in consultation for increasing pain in the mid upper arm. Characteristically, the pain
intensified at night and subsided with aspirin.
Plain film shows a small, intracortical, radiolucent
focus (nidus), surrounded by dense reactive
periosteal bone. The lesion is located in the mid
portion of the humeral shaft.
If the nidus is removed intact, it appears
as a circumscribed portion of red,
trabecular bone, usually less than 1cm in
size.
Low-power view shows the lesional tissue ("nidus"), well
demarcated from the surrounding sclerotic bone.
The lesion is composed of thin, often interconnected
spicules of osteoid and woven bone rimmed by
osteoblasts. Osteoclast-like giant cells can be seen.
Intervening fibrous stroma shows prominent
vascularity.
METASTATIC BONE TUMORS
• Metastatic tumors are the most common
malignant tumor of bone.
• Pathways of spread:
• Origin:
• The radiologic appearance of metastases
• THANK YOU