Sarcoma Flashcards
1
Q
Site of metastatic disease
A
- For extremity: lung, bone, soft tissue
- For retroperitoneal: liver
2
Q
Histologies with higher risk of nodal metastases
A
CARE
- Clear cell
- Angiosarcoma
- Rhabdomyosarcoma
- Epithelioid
3
Q
Physical exam features for sarcoma
A
- ROM
- Pain
- Swelling
- Neurologic dysfunction
- Pulses
4
Q
Necessary workup
A
Try to obtain imaging prior to biopsy –CT/MRI –+/-PET –Plain film of chest or CT chest –Special imaging
5
Q
What other imaging does myxoid sarcoma require
A
MRI spine
6
Q
What other imaging does alveolar soft part sarcoma or angiosarcoma require
A
MRI brain
7
Q
After imaging of sarcoma –> next step
A
Biopsy
- Core is preferred
- Incisional
- Excision is lowest priority given risk of non-oncologic surgery
8
Q
When would an RP sarcoma get biopsied
A
If preop RT is planned
9
Q
What dictates sarcoma grade
A
- Mitoses
- Atypia
- Necrosis
10
Q
Sarcoma T1
A
<5 cm
11
Q
Sarcoma T2
A
5-10 cm
12
Q
Sarcoma T3
A
10-15 cm
13
Q
Sarcoma T4
A
>15 cm
14
Q
Stage IA sarcoma
A
T1 G1
15
Q
Stage IB sarcoma
A
T2-T4 G1
16
Q
Stage II sarcoma
A
T1 G2 or G3
17
Q
Stage III
A
T2-T4 G2-3
18
Q
Management of stage I tumors
A
- Several options
- Surgery alone with observation (preferred for T1)
- Surgery plus adjuvant RT if close or positive margins (more if IB)
- Pre-op RT –> surgery
19
Q
Principles of sarcoma surgery
A
- Limb sparing
- Wide local excision with 1-2 cm of margins
- Place clips at any area of concerning margin
- Resect biopsy and scar
- Closer or positive margins are acceptable at major nerves/vessel/bone or areas that cause functional deficits
20
Q
Indications for neoadjuvant RT
A
- Amputation would be necessary with surgery
- Poor functional outcomes anticipated
- Concerns about margin +
21
Q
Indications for postop RT
A
- Close or positive margins (<1 cm) and reresection not possible
- Larger size (T2+)
- Higher grade (G2-G3)
22
Q
What is the benefit of RT for sarcomas
A
Improves local control (70% –> 90%)
No difference in OS
23
Q
Management of stage II tumors
A
- Surgery +/- Adjuvant RT
- Pre-op RT –> surgery
- Brachytherapy
24
Q
What is the management of stage III sarcomas?
A
- Preop RT –> surgery
- Surgery –> RT + chemo
- Brachytherapy
25
What chemo regimen is recommended for sarcomas?
doxorubicin containing regimen, single or multi-agent
26
What is the preop dose for sarcomas?
50 Gy in 25 daily fractions of 2 Gy
27
What is the postop dose for extremity sarcomas?
* Negative margins: 60 Gy
* Microscopic margins: 66 Gy
* Gross positive margins: 70 Gy
28
What is the benefit/tradeoff of preop RT
* Benefits
* More defined targets
* Smaller targets
* Lower dose
* Less fibrosis/joint stiffness and edema
* Less hypoxia
* Downside
* More wound complications post op, especially LE
* Delays surgery
29
What is anticipated rate of wound complications preop vs. postop
* Preop: 35%
* Postop: 17%
30
What are the 5 year OS rates for stage I-III tumors
* stage I: 85-90%
* stage II: 70-80%
* stage III: 70-80%
31
Downside of postop RT
More fibrosis, joint stiffness, edema
32
Management of N1 or M1 sarcoma
Doxorubicin containing chemo
SBRT or surgery for up to 4 spine or lung mets
33
General principles of STS RT treatment
* CT and MRI sim if possible or fuse T1 post contrast and T2 sequences
* Spare \>1 cm of limb cross section to reduce edema risk
* Treat \< 50% of bone circumference if possible
* Avoid joint space or exclude after 40-45 Gy
34
What RT approach should be used for STS
IMRT with faily KV/CBCT
35
CTV margins for preop RT
* If GTV \>8 cm
* CTV = gross disease + T2 edema + 3cm longitudinal, 1.5 cm radial
* If GTV \<8 cm
* CTV = gross disease + T2 edema + 2cm longitudinal, 1 cm radial
36
CTV margins from GTV for large sarcomas
3 cm longitudinal
1.5 cm radial
37
When should postop RT start?
10-20 days postop for healing
38
What is the contouring strategy for postop RT for STS?
* CTV50: tumor bed, scar, drain sites + 4 cm longitudinal, 1.5 cm radial
* CTVboost: tumor bed + 2 cm longitudinal, 1.5 cm radial
39
Boost doses for postop RT
If R0: 60 Gy
If R1: 66 Gy
If R2: 70 Gy
40
Strategy if preop given and then margin positive
Give boost dose post op
srugical margin + 1 cm
41
Anus/vulva constraint
V30 \<50%
42
Testis constraint
V3 \< 50%
43
Femoral neck
V60 \< 5%
44
Joint constraint
V50 \< 50%
45
Skin strip constraint
V20 \< 50%
46
PTV coverage goal for sarcomas
* V97% = 99%
* V110% \<20%
47
Follow-up recs for sarcomas
MRI primary and CT chest q3m x 2years --\> q6m x 2-5 years --\> annual
48
Complications for STS
Wound complictions
Fibrosis and decreased ROM
Weakening of bone/fracture
Limb length discrepancies
Lymphedema
Dermatitis, hyperpig, telangiectasia
5% risk of second malig
Compartment syndrome (dex and fasciotomy)
49
Staging of RP sarcomas
same as extremity
50
Management of RP sarcomas
In general, if resectable should go to surgery straight
If concern about margin--\> core needle biopsy --\> neoadjuvant RT (45-50 Gy) --\> maximal safe surgery
51
What is the rate of local failure for RP sarcoma
50-80%
52
What is 5 year OS for RP sarcoma
30-60%
53
What histology for RP sarcoma has poorest outcomes
leiomyosarcoma (highest rate of DM)
54
What is the controversey of preop RT
Recent trial demonstrated no difference in abdominal RFS but this was a controversial primary otucome.
The LF was significant reduced (50%) with RT
55
When should postop RT be done for RP sarcoma
Maybe +margin but very discouraged due to high GI toxicity
56
Simulation for RP sarcoma
Supine, alpha cradle, 4dCT, PO/IV contrast, fuse with diagnostic CT and MRI
57
Contouring for RP sarcoma
* GTV = gross disease
* ITV = accounting for motion
* CTV = 1.5 cm expansion (edit of organs, bones), with only 5 mm extension into bowel
* PTV = 5 mm expansion, daily CBCT
58
Management of desmoid tumors
Surgery is best with wide margins (2cm+)
If R1: 50 Gy if re-resection not possible
If R2: re-resect or RT (50 Gy)
59
What if desmoid is unresectable?
56 Gy or systemic therapy
Use wide margins
60
