Tumors

Question 1

Presentation of tumors and tumor like lesions of the bone?

What should eval include?

Answer 1

both benign and malignant:

• persistent skeletal pain and swelling, mil discomfort
• limited of motion
• spontaneous fx
• night pain (malignant)
• proceed w/ clinical, radiographic, lab and bx exam
• anyone over 40:
  think mets: prostate, breast

Question 2

Diff tumors of the bone?

Answer 2

osteoblastic CT tumors:

• osteoid osteoma: pain usually relieved by aspirin
• osteosarcoma: resection and chemo

Cartilage tumors:

• enchondromas
• chondromyxoid fibromas
• chondrosarcomas

bone tumors:

• giant cell: 50% are benign
• chondroblastomas: almost always benign
• ewing’s sarcoma: 50% mortality rate in spite of chemo, rad and surgery

Question 3

What are sxs that pt to malignant tumor of the bone?
Xray findings - that pt to malignancy?
PE findings?

Answer 3

• night pain, constant pain, unusual sxs, no improvement w/ conservative management, or general sxs such as fever, malaise, weakness
• if over 40, weakness: MM
• xray findings: lytic or blastic bone changes, soft tissue calcification or periosteal reaction
• PE: unexplained mass, especially in the thigh

Question 4

Eval of pts w/ suspected tumor of the bone?

Answer 4

• PE and xrays for most
• possible bone scan, CT, MRI, CXR/CT for more high risk lesions
• consider:
  lab tests (CBC, Ca, Phosphorous, alk phos - bone breakdown)
• consults/referral oncologist, path

Question 5

How should a bx be done?

Answer 5

• ideal if performed by surgeon (one who knows what he/she is doing)
• longitudinal and stay in 1 compartment
• consult to plan incision

Question 6

Tx of bone tumor?

Answer 6

• clearly benign: observation vs excision/curettage
• possibly malignant: consider referral to regional cancer center having teams of pathologists, radiologists, surgeons and oncologists and radiation therapists

Question 7

Classification of tumors?

Answer 7

• bony vs soft tissue
• benign vs malignant
• primary vs mets

Question 8

Prognosis of malignant bone tumors?

Answer 8

• prognosis greatly improved in recent yrs w/ dedicated referral centers, pre-op chemo, limb sparing procedures

Question 9

Common characteristics of osteosarcoma? Imaging?

Answer 9

• 2nd MC primary bone tumor after myeloma
• high risk mets
• 20% of all bone sarcomas
• 2nd decade (10-20yo)
• male=female
• appendicular (50% knee - clicking, chronic pain in knee) - 90% in metaphysis of long bones (MC femur, tibia, humerus) - bone pain/jt swelling, palpable soft tissue mass
• MC mets lungs (usually COD)
• XRs mixed lytic/sclerotic w/ cortical destruction (Codman’s triangle - ossification of raised periosteum, “star burst” periosteal rxn)
• MRI
  management: limb sparing resection (if not neovascular), amputation (if neovascular), Chemo as adjuvant tx

Question 10

Characteristics of Ewing’s Sarcoma?

Answer 10

• highly anaplastic
• small round cell tumor in sheets
• MC in males 5-35y, femur and pelvis MC location
• bone pain, +/- palpable mass, may have jt swelling, +/- fever
• Dx:
• newer lab tests to differentiate
• long bone diaphyses, lytic, moth-eaten, indistinct margins, “onion skin”**
• really aggressive
• management: chemo, surgery, and rad
• survival rates now 80-90% w/ pre-op chemo (vs 20%)

Question 11

Soft tissue tumors - why are they challneging? Diff types and modes of resection?

Answer 11

• challenging: hx rarely helpful, xrays usually negative
• small (less than 5 cm) superificial cystic lesions usually benign/observed
• large deep solid tumors: studies/bx
• type of resection: intralesional, marginal, wide and radical

Question 12

Classes and staging of soft tissue tumors?

Answer 12

class based on apparent differentiation:

• fibrous: Dupuytren’s, desmoid
• lipomatous: lipoma, liposarcoma
• smooth muscle, striated muscle, vascular, synovial, neuro
• staging: tumor grade, location, extension, mets

Question 13

MC cuase of bone destruction in an adult? Most common areas?

Answer 13

• Mets: breast, lung, prostate, kidney, all common, go to bone
• spine, ribs, pelvis, proximal limb girdles MC
• initial presentation may be to orthopedist w/ pain (low back and thoracic pain)

Question 14

What are common pitfalls of dx bone tumors?

Answer 14

• assume metastatic, not recognizing that a fx is pathologic, inadequate w/u, planning, fixation, not knowing when to refer
• tx: fx risk, fxn, palliation, other

Question 15

What are some common benign bone tumors?

Answer 15

• osteochondroma
• osteoid osteoma
• bone cyst
• nonossifying fibroma

Question 16

Characteristics of an osteochondroma? Management?

Answer 16

• MC (35-50%) of benign and about 15% of all primary bone tumors
• not true neoplasms
• knee/proximal humerus - 2:1 males
• 10-20y
• begins in childhood and grows until skeletal maturity (if it doesn’t stop - be concerned it is something else) , may precede chondrosarcomas
• mostly mechanical problems/compression, space occupying
• often pedunculated, grows away from growth plate, and involves medullary tissue, pelvis is MC site of malignant transformation
• CT/MRI if unclear
• surgery: completely excise cartilage and perichondrium

Question 17

Osteoid osteoma characteristics? Imaging, tx?

Answer 17

• benign
• nidus: well demarcated, bone forming, up to 1 cm, approx 10% of benign bone tumors and 2-3% of all primary bone tumors
• 2nd and 3rd decades: Male to female 3:1
• long bones: lower extremity, cortex, posterior elements lumbar spine
• dull/sharp pain, worse at night, better w/ aspirin/NSAIDs

Imaging- XR/CT

• En bloc resection (CT, XR) w/ lymph drainage
• percutaneous radiofrequency ablation

Question 18

Characteristics of unicameral bone cyst? Tx?

Answer 18

• ages 5-15, boys 3:1 over girls
• 50-60% prox humerus
• not true cyst
• central radiolucent lesion metaphyseal side of growth plate, long bones
• MRI if unclear
• curretage/graft: 20% to 45% recurrence
• needle aspiration and several steroid injections at 2 month intervals - 10% recurrence

Question 19

What is FCD-NOF (fibrous cortical defect/non ossifying fibroma)?

Answer 19

• common in childhood
• approx 5% of benign primary tumors
• non-neoplastic
• metaphysis of long bones (knee)
• occurs in first 2 decades
• oval elongated radiolucent, well marginated
• if weakening bone then curettage/graft
• prone to fx: if fx immobilize, observe, sometimes lesions will heal

Question 20

What is critical in bone tumor care?

Answer 20

• early detection/tx/referral can be critical