Bone and Joint Pathodiagnosis Week 6

What is the name of a new growth or tumor?

Neoplasm

What does the suffix "-oma" mean?

benign

What does the suffix "-sarcoma" mean?

malignant

What is the term used to describe a tumor which has spread?

metastasis

What kind of bone tumor adds bone?

Blastic

What kind of bone tumor removes bone?

Lytic

What kind of bone tumor both adds and removes bone?

Mixed

What age group is typically affected by primary tumors?

less than 35 yo

Which bones are typically affected by primary tumors?

Those in the appendicular skeleton

What % of malignancies do primary tumors account for?

30%

What type of tissue is affected by primary tumors?

Connective tissue (bone, cartilage)

What % of malignancies do secondary tumors account for?

70%

Which bones are primarily affected by secondary tumors?

Those in the axial skeleton

Where do carcinomas originate?

epithelial tissue (breast, prostate, lung, etc)

What age group is typically affected by secondary tumors?

Greater than 40 yo

At what point in the skeleton do secondary tumors typically not occur past?

Knee and elbow

What is the most common malignancy of the bone?

Metastatic carcinoma

What % of metastatic carcinoma arises in the breast, lungs, and kidneys?

80%

What is the most common source of bony metastasis in women?

Breast (70%)

What is the most common source of bony metastasis in men?

Prostate (60%)

Lung (25%)

What is the most common pathway for bony metastasis

Hematogenous (via batson's venous plexus

What is batons venous plexus?

A system of veins with thin walls, connected to many bones of the axial skeleton

T or F: Bones rich in yellow marrow are common sites of metastasis

False (bones rich in red marrow are)

What is the most common type of metastatic bone lesion?

lytic (75%)

How much of bone much be eroded for a metastatic lesion to be visible on x-ray?

30-50%

What is the most common site of bony metastasis?

Spine (40%)

Which parts of the spine more commonly develop bony metastasis?

Thoracic and lumbar spine

What parts of the vertebra are more commonly affected by bony metastasis?

vertebral bodies and pedicles

What are the AKAs of pathological compression fracture?

vertebra plana

universal compression fracture

pancake vertebra

What are the three causes of pathological compression fracture?

osteoporosis, multiple myeloma, and metastasis

What lab finding indicates blastic metastasis?

Elevated alkaline phosphatase

What lab finding indicated prostate metastasis?

Elevated acid phosphatase

What is the term for a uniform white appearance of vertebra on X-ray, indicating blastic metastasis?

Ivory vertebra

In what organs is cortical metastasis most common?

Lung, breasts, and kidneys

What is the term for metastasis that occurs distal to the elbows or knees?

Acral metastasis

What is the term for the x-ray appearance where one pedicle of a vertebra has been completely destroyed?

Winking owl sign (one-eyed pedicle sign)

What is the term for the x-ray appearance where both pedicels of a given vertebra have been completely destroyed?

Blind owl sign

What indicates whether a winking owl sign is due to a congenital disorder rather than a neoplasm?

The opposite pedicle will be hypertrophied

What is the order of most-to-least common primary malignant bone tumors?

MOCE

Multiple myeloma

Osteosarcoma

Chondrosarcoma

Ewing's sarcoma

Which primary malignant bone tumor arises from malignant proliferation of plasma cells and an overproduction of IgG?

Multiple myeloma

What is the AKA for multiple myeloma?

Plasma cell myeloma

What is the most common primary malignancy of bone?

Multiple myeloma

What gender is more affected by every type of primary bone tumor?

Males

What age group is more affected by MM?

Greater than 25 yo

What causes the lytic destruction of bone in MM?

stimulation of osteoclast activating factor by myeloma cells

What are the symptoms of MM?

Bone pain, bacterial infection, renal failure

What is the most common presenting symptom of MM?

Bone pain

What is the primary cause of death in MM patients?

Bacterial infection

What is the name of the multiple, sharply circumscribed, round, lytic defects caused by MM?

Punched-out lesions

Where do the lesions of MM take place?

The medullary cavity

What are the lab findings of MM?

Reversed A/G ratio

M-protein spike on electrophoresis (99%)

Bence-jones proteinuria (60-70%)

Anemia

Hypercalcemia

Normal alkaline phosphatase

What causes the increased A/G ratio in MM

A is albumin, G is globulin

G increases relative to albumin due to the proliferation of IgG

How fast do patients with MM die?

3-4 years (90%)

What is the treatment for MM?

palliative (chemotherapy, radiation, analgesics, adequate hydration, maintain ambulation)

What is the name of the x-ray appearance of multiple punched out lesions in the skull of MM patients?

Raindrop skull

What is the name of a malignant tumor of mesenchymal cells characterized by direct formation of osteoid by the tumor?

Osteosarcoma

What does an osteosarcoma cause excessive formation of?

Osteoid

What is the second most common primary bone tumor?

Osteosarcoma

Which two primary bone tumors affect young people?

Osteosarcoma

Ewing's sarcoma

What is the most common site of pain in osteosarcoma patients?

Around the knee (Distal femur, proximal tibia)

What part of the bone is the most common site of osteosarcoma?

Metaphysis (75%)

What % of people who die of osteosarcoma have metastasis to the lungs?

90%

What are other common sites of metastasis in osteosarcoma?

Bones (50%) and kidneys (12%)

What is the treatment for osteosarcoma?

Amputation and chemotherapy

- 75% survival rate if no metastasis

What is a malignant tumor of chondrogenic organ which arises from chondroblasts and remains cartilaginous throughout its development?

Chondrosarcoma

What age group is most affected by chondrosarcoma?

40-60 yo

T or F: Chondrosarcoma is slow growing

True

What are the most common sites of chondrosarcoma?

Pelvis and proximal femur

What shape is the lesion of chondrosarcoma?

round or oval

What x-ray finding is in 2/3 of chondrosarcoma patient's tumor matrix?

Mottled calcification

What type of periosteal response is found in chondrosarcoma?

Laminated or spiculated

T or F: Biopsy can be used to diagnose chondrosarcoma

True

T or F: Chondrosarcoma has the worst prognosis of the primary metastatic bone tumors

False (it has a better prognosis than other primary bone malignancy)

Where can chondrosarcoma metastasize to?

Lungs

What is a highly malignant bone tumor arising from primitive stem cells?

Ewing's Sarcoma

What long tubular bone is the most common site of Ewing's Sarcoma?

Femur (50% of long bones)

What flat bone is the most common site of Ewing's Sarcoma?

Pelvis (50% of flat bones)

What is the classic location of Ewing's sarcoma?

Diaphysis

Which primary bone tumor presents clinically like an infection?

Ewing's Sarcoma

Where does Ewing's Sarcoma commonly spread to?

Lungs

What is the common lesion of Ewing's sarcoma?

Lytic

What is the name of extension of Ewing's Sarcoma into the haversian system subperiosteally?

Cortical saucerization

T or F: Biopsy can be used to diagnose Ewing's Sarcoma

False (it may not distinguish it from other neoplasms)

What is the treatment for Ewing's sarcoma?

Surgery

Chemotherapy

Radiation therapy

What is the name of the laminated periosteal reaction of Ewing's Sarcoma as seen on X-ray

Onion Skin

What is the AKA for Osteochondroma?

Exostosis

What is the name of a bony projection from the external surface of endochondral bone with a cap of hyaline cartilage?

Osteochondroma

What is Solitary osteochondroma?

Exosostosis of a single bone

What is multiple osteochondroma?

Exostosis of 2-3 bones

What is an AKA for osteochondromatosis?

Hereidatary multiple exostosis (HME)

What is the average number of exostoses in HME?

10 (can be a few to hundreds

What is the most common benign tumor of the appendicular skeleton?

Osteochodnroma

What % of all bone tumors are osteochondromas?

10-15%

What age group is most affected by osteochondromas?

less than 20 yo (75%)

What gender is most affected by osteochondroma?

Males (2-3x)

What is the most common site of osteochondrosis?

Metaphysis

What % of osteochondromas malignantly degenerate to a chondrosarcoma?

1%

What % of HME exostoses will lead to malignant degeneration?

20%

What is the name of a narrow-stalked exostosis?

Pedunculated

What is the name of a flat-based exostosis?

Sessile