Bone Cysts and Tumors Flashcards
Pre-operative evaluation
- History and physical
- Radiographic evaluation
- labs
- Type of tumor
- Local and distant involvement
- Recurrence rate
- Age
- Occupation
- Lifestyle
Lytic lesions
- Lytic lesions that occur in the lower extremity
are not common, but you need to be aware of - Boards will include this a great deal
Ill- defined lesions
o Indicates that the lesion is a fast growing tumor
o No real parameters
o very hard to determine the area the lesion is limited to
o Hard to tell if surrounding tissues (bone or soft tissue) are affected
Well-defined lesions
o AKA a “geographic” lesion
o This indicates that the lesion is slow growing
3 types of lesion appearances
- Geographic
- Moth-eaten
- Permeative
Example of geographic lesion
Bone cyst
- Very well-defined, geographic lesions
- Cystic changes in the bone are common (bone cyst)
- Not necessarily something you need to treat
- Need for treatment depends on the size of lesion and if any secondary problems are occurring
- Not unusual to see a pathological fracture around this – this then NEEDS to be treated
- If no pathological fractures, you can just do serial radiographs over a number of years
Example of moth eaten appearance
- Multiple lucent changes that are not well defined
- This is a very good example of what a moth-eaten appearance
- NEED to know this image ***
Example of permeative appearance
- No true beginning or end, no well-defined area
- On the left side, you see some subtle changes, but no well-defined area
- Same thing on the right – you see some lucent lytic changes
but you also see that more proximally as well
NOTE - clinical approach to diagnosing bone lesions
- The first thing you do is determine the appearance (geographic, moth-eaten,
or permeative), which will give you an idea of how benign or malignant the lesion is - Geographic is typically the most benign, permeative is typically the most malignant
- The next step is to assess the margins and periosteal reaction…
Narrow margins
o 0.1-1.0 mm tumor and surrounding normal bone are touching, and you see a very small distance between them
o Usually can’t tell the difference between 0.1 and 1.0 mm – just know it is very narrow
Wide margins
o 2-10 mm can see where the tumor is, and you can see where there is undamaged bone, but in between the two there is an area that is indistinct that looks like it might be partially damaged
Poorly defined margins
o Correlates with permeative lesions
o May be several centimeters or it may be impossible to measure the margin
o One can tell there is a tumor in the bone, and there are areas that are distinctly abnormal, but you can’t tell how big the lesion is or where it begins or ends
NOTE about margins
o The margins will also correlate to the level of aggressiveness (benign vs. malignant)
o If you have a narrow, well defined margin, it is typically a more benign lesion
o If you have a wide margin, there is likely activity taking place there, more aggressive and more likely to be malignant
Description of periosteal reaction
- Periosteal reaction is an indicator of biologic activity of the bone lesion, indicating a more aggressive tumor
- This occurs on the outside of the bone (associated with the periosteum)
- If the lesion is expansive or if there is a lot of bone activity, you will likely see periosteal reaction associated with it
Types of periosteal reaction
o Solid o Lamellar o Multilamellar o Spiculated o Buttress o Codman’s triangle
Solid periosteal reaction
o There is expansion of the lesion, but it is growing at a slow enough rate that the bone is able to keep up with it and lay down new bone surrounding the growth – this allows for a solid periosteal reaction
Lamellated periosteal reaction
o Multiple layers of periosteal reaction which appears like an “onion skin”
o The lesion is growing, but again the body does have a chance to lay down bone, but in this case it is in multiple layers
Spiculated periosteal reaction
o “Sun-burst” or “hair-on-end” appearance
o Sharpey’s fibers become stretched out perpendicular to the bone, and then ossify
o The body does NOT have a chance to lay down a solid layer of bone due to the rapid growth of the lesion
o Results in a spiculated or “sun burst” reaction which appears like a “hair on end”
Codman’s periosteal reaction
o Only the edges of the raised periosteum will ossify
o This little bit of ossification forms a small angle with the surface of the bone, but not a complete triangle
o Very aggressive, again the body does not have a chance to lay down bone due to very rapid growth
Example of spiculated periosteal reaction
- What the diagram looks like and what the radiograph
looks like can be very different - In this example, you mostly see a light “rim” around the
lesion where it looks “fluffy” - You don’t actually see all the little spicules coming out of
the bone
Example of Codman’s triangle
- Only the edges of the raised periosteum will ossify
- This little bit of ossification forms a small angle with
the surface of the bone, but not a complete triangle - You will NEED to do some type of biopsy which will give
you more definitive information
Example of lamellar periosteal reaction
- This is a good example of what lamellar or onion skinning
will look like, you can see the actual layers
Staging of benign lesions
o Stage 1: lesions that are static or tend to heal spontaneously.
o Stage 2: lesions that present with a more aggressive radiographic presentation, and evidence of continued growth.
o Stage 3: locally aggressive lesions, and show progressive growth not limited by barriers – can see invasion into cortical bone or joints.
o Stage 2 and 3 are histologically immature
Treatment for benign stage 1 and 2
Note: treatment is based on STAGE***
o Intra lesional curettage
o Reconstructed with cancellous bone grafting, methyl methacrylate augmentation
Treatment for benign stage 2 and 3
Note: treatment is based on STAGE***
o Over treat with marginal excision that removes the intra articular surface with associated fusion – take more than just the lesion to assure complete removal
Adjunct therapy for benign lesions
o Cryotherapy where you remove healthy bone in the area with either phenol or polymethacrylate – used in combination with the bone packing
Staging of malignant lesions
o Stage 1: low grade lesions
o Stage 2: high grade lesions
o Stage 3: presence of metastasis
Treatment for malignant stage 1 lesions
Note: treatment is based on STAGE***
o Requires a wide marginal excision, may require a partial or complete amputation at the appropriate level
Treatment for malignant stage 1B (hybrid of stage 1 and 2) and stage 2 lesions
Note: treatment is based on STAGE***
o Reconstruction and/or amputation, but this will be more aggressive
o If unsure, consult oncology, especially if chemotherapy/radiation may be necessary
Bone biopsy types
- Fine needle biopsy
- Core needle biopsy
- Excisional biopsy
Principles of bone biopsy
Incision placement and orientation
o Longitudinal and based on the anticipated area of resection
o Performed without the formation of tissue planes
o Hemostasis
- Dissection should be carried out sharply to the level of bone and remain within one fascial compartment
- Soft tissue mass sent if present
- Cortical window created
- Closed in layers
CASE STUDY I
- 12 year old male presents with a chief complaint of right heel pain 2 weeks duration
- Initial presentation secondary to increase in level of activity
- PMH: unremarkable, Med: none, NKDA
- Initial treatment: ibuprofen 600mg. Bid, modify level of activity.
- What are some differentials that would be appropriate for a 12 year old male? Fracture, NOT plantar fasciitis (not in adolescents), Sever’s disease, bone cyst
- CT shows a large lytic lesion in the calcaneus
Treatment for CASE STUDY I
o Creation of a cortical window, curettage of tumor and adjacent bone
o Packing of the defect (tri-cortical graft) iliac crest
o Below knee cast and non-weight bearing (until you start to see integration)
CASE STUDY II
- 37 year old male presents with pain to the right hallux of 4 months duration. Pain associated with ambulation and weight bearing activities.
- Bone scan shows increase in uptake in the proximal portion of the hallux
- MRI shows pathology in the base of proximal phalanx – lesion is present here and it is well-defined (you see some gray uptake, but that is just swelling)
Treatment for CASE STUDY II
o Treatment: excision of the lesion with bone curettage
o Packing with allogenic bone graft
o You can see the bone packing on radiographs post-op
CASE STUDY III
- 14 year old male presents with a history of heel pain, unresponsive to conservative treatment
- Radiographs show a very large, well-defined lytic lesion of the calcaneus
- Patient taken to surgery, bone window created and defect packed with allogenic bone graft matrix, then you put the bone window back on to increase stability on the lateral calcaneus
- The pathology report indicated findings consistent with an aneurysmal bone cyst
CASE STUDY IV
- 27 year old female presents with a chief complaint of stiffness and periodic pain in ankle joint
- PMH: unremarkable, neuro/vascular intact, musculoskeletal: limited ROM of the ankle joint
- X-ray shows portion of normal tibia with area of lucent change in medial portion of distal tibia
- MRI shows a well-defined lesion, consistent with the radiographs
- The MRI is used to determine if there is any soft tissue involvement and here we see that the lesion is limited to the tibia
Diagnosis for CASE STUDY IV
Diagnosis is an Intra-osseous ganglion
o Just by looking at it you can tell it is a ganglion (sac filled with viscous or gel material)
o Typically ganglions are associated with tendons, ligaments or capsular structures
o Here we see the ganglion associated with the articular surface of the bone
Even though it looks like a ganglion structure, you would still send to pathology just to be safe
CASE STUDY V
- Patient presents with pain and large prominence along the 5th metatarsal head
- Lesion is dorsally and plantarly located, comes close to bone
- MRI shows that it is a well-defined lesion, even though there is invasion into the soft tissue, it is not integrated into the soft tissue, it is still its own structure – This is the important information you can gain by looking at MRI
- Diagnosis was a chondroma – this in itself is not necessarily a bone tumor, but it is a tumor associated with the articular surface
- Any time you have a lesion, you need to have a good understanding of the pathology
CASE STUDY VI
- 57 year old female presents with a recent onset of severe pain to the hallux.
- PMH: NIDDM w/ neuropathy, HTN
- Objective findings: DP and PT +1/4, epicritic sensation intact, atrophic, scaly, xerotic skin, +5/5 extrinsic muscles, pain on palpation to the hallux
- MRI shows increase in activity, lesion present within the base of the proximal phalanx
- Treatment consists of curettage and packing the area
- Follow up MRI shows a walled off appearance of the bone packing site
CASE STUDY VII
- An 11 year old male presents with a chief complaint of a left painful 2nd digit with no history of trauma, pain associated with shoe gear
- PMH: unremarkable, meds: none, surgical history: none
- The first radiograph taken shows a tiny change in the bone, the second radiograph taken 1 month later shows a fast growing lesion is present at the distal phalanx
- Treatment: Symes amputation of the 2nd digit – just removed a part of the distal bone, no soft tissue loss was necessary
- Pathology report: findings consistent with chondroma (non-malignant)
