Bone, Cartilage and Soft tissue tumors: Clinical Correlations

Question 1

Examples of common bone lesions.

Answer 1

Metstatic carcinoma

Multiple myeloma

Lymphoma of bone

Osteosarcoma

Ewing sarcoma

Unicameral bone cyst (UBC)

Aneurysmal bone cyst (ABC)

Enchondroma

Osteochondroma

Chondrosarcoma

Question 2

Examples of soft tissue lesions.

Answer 2

Lipoma

Desmoid

Soft tissue sarcoma

Lymphoma

Question 3

What are some tests/imaging that are helpful for staging a bone lesion?

Answer 3

• X-ray of entire affected bone
• Whole body bone scan (or skeletal survey – multiple myeloma)
• CT scan of chest, abdomen and pelvis OR PET/CT
• Serum protein electrophoresis/Urine Protein Electrophoresis/Serum free light chains–multiple myeloma or plasmacytoma [don’t forget about labs!!]
• Prostatic specific antigen (for prostate adenocarcinoma)

Question 4

What is multiple myeloma?

Answer 4

A common lymphoid malignancy – sheets of plasma cells with atypical cell features

Question 5

When does multiple myeloma present in individuals?

Answer 5

Median age is 70 yo

Question 6

What part of the bone does multiple myeloma affect?

Answer 6

Principally invovles bone marrow and causes lytic lesions throughout the skeleton (most commonly vertebrae, ribs, skull, pelvis, femur, clavicle, and scapula)

Results in “pathological fractures”

Question 7

Why does multiple myeloma do what it does?

Answer 7

Cells produce a monoclonal immunoglobulin, most often IgG.

Question 8

What marker identifies B cells?

Answer 8

CD20

Question 9

Neoplasms composed of lymphocytes resembling a normal stage of differentiation

Answer 9

Lymphomas

Question 10

Most common type of lymphoma in adults, derived from clonal B cells

Answer 10

B-cell lymphomas

Question 11

What happens if a soft tissue biopsy results shows glands?

Answer 11

Probably a metastatic (ie lung) cancer – primary soft tissue cancers do not show this

Question 12

Most common type of lung cancer in woman and nonsmokers

Metastases early (to bone, brain, and liver)

Answer 12

Lung adenocarcinomas

Question 13

What is the biological marker that is positive in adenocarcinomas arising in the lungs?

Answer 13

TTF1

Question 14

What is a potential cause of unicameral bone cysts?

Answer 14

Increased intraosseous pressure

Question 15

Are unicameral bone cysts benign or malignant?

Answer 15

Benign

Question 16

What ages do unicameral bone cysts affect? And where do they present in bone?

Answer 16

Children and young adults

Metaphyseal region of long bones

Usually proximal femur or humerus

Present as pathological fracture

Question 17

How do unicameral bone cysts occur? What do they look like pathologically?

Answer 17

Bone cortex is eroded by the cyst and elicits secondary periosteal new bone formation

Pathology: cyst filled wtih clear fluid and lined with thin fibrous membrane; because of frequent fractures old blood (hemosiderin) and granulation tissue may be present

Question 18

How do they treat UBC?

Answer 18

Aspirate inject into them, suck out and put in steriods or Ca/PO4 matrix

Question 19

What are aneurysmal bone cysts (ABC)?

Answer 19

Eccentric solitary expansile lesion

Benign neoplasm with characteristic translocation

Question 20

How do ABC’s present? Where do they commonly occur?

Answer 20

Swelling, pain and tenderness

Occur in metaphyseal region of long bones – but any bone may be involved

Question 21

What do ABC’s look like pathologically?

Answer 21

Cystic spaces filled with blood but no endothelial cell lining

Between the blood filled speaces are fibrous septa, giant cells and immature bone or osteoid

Question 22

How are aneurysmal bone cysts treated?

Answer 22

Embolization/sclerotherapy

Question 23

When should you NOT try to remove “lipomas” in clinic?

Answer 23

Bigger than 3 cm or deep mass – get an MRI

Question 24

Lipoma

Answer 24

A lipoma is a slow-growing, fatty lump that’s most often situated between your skin and the underlying muscle layer. Often a lipoma is easy to identify because it moves readily with slight finger pressure. It’s doughy to touch and usually not tender. You may have more than one lipoma. Lipomas can occur at any age, but they’re most often detected during middle age.

(Thanks Mayo Clinic)

Question 25

Desmoid Fibromatosis

Answer 25

Cytologically bland fibrous neoplasms originating from the musculoaponeurotic structures throughout the body.

Desmoid tumors often appear as infiltrative, usually well-differentiated, firm overgrowths of fibrous tissue, and they are locally aggressive.

(Thanks MedScape)

Question 26

Soft Tissue Sarcoma

Answer 26

Cancerous (malignant) tumors that originate in the soft tissues of your body. The soft tissues include muscle, fat, blood vessels, nerves, tendons and the lining of your joints (synovial tissues).

(Thanks Mayo Clinic)

Question 27

How are chondrosarcoma’s graded?

Answer 27

Grades 1 - 3

Question 28

What are some take home points about biopsy?

Answer 28

• Location determined by person doing definitive surgery
• Avoid contaminating compartments
• Assume a sarcoma if isolated disease
• Communicate with pathologist