Bone & Joint Path II

7/28/2019 Bone & Joint Path II

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Malignant Bone Tumors----

Musculoskeletal---Week 2

Monday, August 08, 2011

Dr. Templeton & ONeil

CASE 1: OSTEOSARCOMAo 13 year old male who first noted

onset of pain in his left proximal

tibial metaphysis 4 months prior

to X-rays. No history of traumao X-rays: Destructive process

within L. proximal tibial

metaphysis.

o Tc99 bone scan revealed uptakein same general area.

o CT of the chest was normal.o Labs Normalo Diagnosis: Osteosarcoma

Most common primary malignant bonetumor

Bimodal age distribution (75% occurin pts < 20 yo)

Mutations in the genes encoding p53and RB

o Pts with hereditaryretinoblastomas at 1,000x more

likely to develop osteosarcoma

Bone infarcts, chronic osteomyelitis,Paget disease, radiation, also

associated with a bone neoplasia

Develop at sites of greatest bonegrowth (metaphysis)


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CASE 2: CHONDROSARCOMAo 72 year old black female with aching

discomfort in her right shoulder, worse

at night. Duration of approximately six

months.

o X-ray: expansile lesion replacing thehead of the right humerus, with

characteristic punctate calcifications.

o Bone scan shows intense uptake inregion of tumor.o Lab: no abnormal valueso Diagnosis: Chondrosarcomao 40 years or oldero Central skeleton pelvis, shoulder, ribso Malignant hyaline and myxoid cartilage


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CASE 3: EWINGS SARCOMAo 7 year old female presented with one month

history of right shoulder pain. She noted an acute

exacerbation while trying to climb a fence on the day

prior to being seen in the office. She had been

running low-grade fevers for approximately a month

without chills.

o X-ray: Permeative lesion involving diaphysis ofhumerus. Bone scan positive only in area of involved

bone. MRI showed extensive marrow involvement

with possible involvement of the proximal growth

plate and a surrounding soft tissue mass.

o Diagnosis: Ewings sarcomao small/round blue cell tumoro Most patients are < 20 years oldo Pain, fever, leukocytosis (import differential is

osteomyelitis)

o Diaphysis of long boneso Sheets of small cells with inconspicuous cytoplasmo Ddx: Metastatic neuroblastoma, metastatic

rhabdomyosarcoma, lymphoma

o Ewings Sarcoma/PNET (peripheral neuroendocrinetumor)

o Similar phenotype, identical translocation SAMETUMOR differing by degree of neural differentiation

o 2nd most common bone tumor in children (2nd toosteosarcoma)

o More common in Caucasians, slightly more commonin boys

o Geneticso 85% t (11;22)o 5-10% t(21;22)o 1% t(7;22)o In ALL cases there is fusion of the EWS gene on

chromosome 22 to a member of the ETS family of

transcription factors, most commonly FLI1

o EWS-FLI1 fusion geneacts as a dominantoncogene constitutively active transcription

factor that stimulates cell proliferationo Treatment

o Chemotherapy and surgical excision +/- radiationo 75% 5-yr survival, 50% long-term cure


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CASE 4: MULTIPLE MYELOMAo 62 year old male presented to family practice physician

complaining of back pain, fatigue and headache Pain is worse

at night and not relieved with aspirin/Ibuprofen

o He also notes he has lost 20 pounds in the last 6 monthso Labs - pancytopenia, proteinuriao X-ray Numerous lytic lesions in skull and spineMultiple Myeloma Summary:

o 50-60 year oldso More common in blacks than whiteso Excess IgGko Bone pain due punched out lytic lesions Production of osteoblast inhibitor Release IL-1 (osteoclast activating factor)

o Ribs, vertebrae, skull, pelvisCASE 5: METASTATIC RENAL CELL CARCINOMAo 46 year old male with a Hx of renal cell carcinomao Presents w/ right hip pain, 10 pound weight losso X-ray: large lesion in right proximal femur that is worrisome

for a fracture

o 1.2 million patients present with cancer each year in theUnited States. Of these, approximately 600,000 persons have

metastases to bone.

o In contrast, 2,700 patients per year develop primary bonesarcoma.

o The age range of patients with sarcoma is different from thatof individuals with carcinoma of bone; most metastatic bone

lesions occur in adults older than 50 years

o Most sarcomas occur in adolescents or young adults (< 30 y)o A bone-occupying mass in an adult is much more likely to be a

focus of metastatic carcinoma than to be a primary sarcoma of

bone

o Females: Breast and Lungo Male: Prostate and Lungo Others: Thyroid and Renal cell carcinomaMore on Metastatic Carcinoma:

Tumor cells up-regulate osteoclasts through production ofRANK ligand potent stimulator of osteoclastic activity

RANK ligand 1) recruits & 2) activates osteoclastswhich degrade bone, producing pockets or holes in bonefor tumor cells to grow

Parathyroid hormone related peptide (PTHrP) Breast carcinoma cells small cell carcinoma of the

lung

Potent stimulant of osteoclasts

Hip Lesion

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Bone & Joint Path II