Tumors of Bone

Patrick Henderson, M-IV USCSOM August 28, 2007

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Intro

Bone tumors are very diverse in morphology and biological potential (can be no big deal or rapidly fatal) MOST bone tumors are benign lesions Most benign lesions are seen <30 years of age A new bone tumor in the elderly is more likely to be malignant No bone is safe (though most primaries are in long bones) Locale in the bone gives important Dx info More common benign lesions typically present as incidental findings (non-painful, stable size) Be cautious with painful lesions and those that grow relatively fast (over weeks or months) Pathological fracture can be the first sign of tumor

     Bone neoplasms are very difficult to diagnose specifically on radiologic testing alone So why is radiology important?

 Exact location of lesion   Extent of growth/metastasis Aggressiveness Best test for Dx= X-ray Best test for staging= CT or MRI Quick shout out to the pathologists– histologic grade is the most important prognostic feature of bone sarcomas and essential for staging most of the bone tumor types.

Example:

Cases

Find the lesion

Example: RIGHT THERE!

Cases

Find the lesion

Case I

 16 yr old white male with pain in his left upper arm.

 Mild swelling and tenderness  Pain progressively getting worse for ~ 3 months  Recent onset of mild fever

Imaging:

Imaging:

**

Biopsy material showed a highly cellular, infiltrative neoplasm consisting of sheets of tightly packed, round cells with very scant cytoplasm ("round blue cell tumor"). Occasional Homer-Wright rosettes were identified. Other fields showed extensive necrosis.

Dx: Ewing’s Sarcoma (or PNET)

     #2 primary bone malignancy in kids (5-15 is most common age group Much more common in Caucasians Typically in the diaphysis of long tubular bones or in large flat bone Lytic tumor w/ permeative margins extending into the soft tissue Periostial rxn creates sheets of reactive bone in an onion-skin fashion

Another most excellent example of “onion skinning”

Case II

 33 yr old black female with sudden severe hand pain after very minor trauma.

 Completely healthy otherwise.

 All labs normal

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Dx: Enchondroma

Benign cartilagenous tumors but hard to distinguish from a low grade chondrosarcoma  Acral bones-- the most common primary hand tumor  Usually solitary, usually incidental finding (non painful unless associated with fracture)  Get hand films and look for dec. lucency but not so much as a cyst (more ground-glass) w/ or w/o areas of stippled calcifications or rings

For boards and wards:

 Multiple enchondromas = ____________  Multiple enchondromas + hemanigiomas of soft tissue = _____________

For boards and wards:

 Multiple enchondromas = Ollier’s Dz  Multiple enchondromas + hemangiomas of soft tissue = Maffucci syndrome

Case III

 50 yr old white male with back pain  Mainly lower spine/sacral pain, progressive ~ 8 months  New onset rectal pain and constipation

CT guided FNA confirmed…

Dx: Chordoma

 Arises from notochord remnants. Thus is typically midline along the spine and usually at the ends (Sacrococc or occ/cervical jxn)  Males>Females, middle age  + staining w/ S-100 and epithelial markers  Locally invasive until very late in disease where mets can go to the lungs, LN, skin.

Case IV

 21 yr old male with new onset chest pain today, worse on inhalation.  ROS significant for an ongoing aching leg pain for the past 6 months which he has put off seeing a doctor for.

Dx: The dreaded Osteosarcoma

   #1 primary bone malignancy Associated with RB1 and p53 gene mutations   1000x greater risk w/ Hx of hereditary retinoblastoma Member of the Li-Fraumeni Syndrome family Bimodal age spike: young and elderly   75%

 Metaphysial tumor  60% at the knee (distal femur or prox tibia)  Radiographic terms to know:  Codman’s Triangle:  “Sunburst” periostial formation:  AKA “Hair on end”

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For the future Surgeons:

Rotationplasty is a new solution to disfiguring surgical resections of lower limb sarcomas:

Quick Hits:

Gout

Incidental finding on knee xray Fabella = posterior sesmoids or little confused knee caps

13 yr old boy with superior tibial pain, r/o neoplasm w/ xray shows:

Osgood Schlatter

Metastatic Disease

     Most common malignant lesion of bone Bone is # 3 on the list of favorite places for mobile cancers to go Malignant lesions are more likely to be in axial bones Typically multifocal BUT renal and thyroid carcinomas are notorious for producing only a solitary lesion Can be lytic, blastic, or both:  Lung is Lytic, Prostate Produces, Breast does Both

 Adults     Lung Prostate Breast Kidney

Mets (cont)

 Kids      NB Wilm’s OS Ewing’s Rhabdomyosarcoma

The End

Thanks for your attention and good luck on applications!

Bibliography

   Robbin’s and Cotran, Pathological Basis of Disease, 7 th Edition MD Murphey, MR Robbin, GA McRae, DJ Flemming, HT Temple, and MJ Kransdorf

The Many Faces of Osteosarcoma

RadioGraphics 1997; 17: 1205 William R. Reinus, Louis A. Gilula IESS Committee

Radiology of Ewing's sarcoma: Intergroup Ewing's Sarcoma Study (IESS)

RadioGraphics 1984; 4: 929-944.     Washington Univ. in St. Louis (website) Harvard Medical School (website) Learning Radiology.com (website… duh) Bonetumor.org (You’re not even reading this are you?)