sarcoma

Question 1

STS adjuvant radiotherapy?
Indications, dose/#.

Answer 1

High risk features:
Size >5cm
Grade 2 or 3 (Trojani)
Location 2 things: deep fascia involvement or location where resection would be difficult.
Margins 2 things: positive or close (Leeds = <1mm)/marginal resection (QART < 2-10mm where re-excision not possible e.g. abuts bone or nerve).

60Gy/30#/6weeks.
66Gy/33#/6.5 weeks if positive margins.

Trjoani score = Grading. Tumor differentiation, Mitotoses/HPF >/=20 = highest, Tumor necrosis >50% = highest. Scored 1-3.

Retroperitoneal STS - don’t usually offer RT.
Pelvic sarcoma - occassionally offer.

Volumes: GTV - reconstructed with clips and pre-op imaging.
CTV = GTV + 2 radially + 5cm sup/inf.
PTV = +5-10 depending on immobilisation.

Reduces local relapse by 1/3 to 1/2.

Question 2

Neo-adjuvant RT STS?
Indications, dose/#.

Answer 2

For resectable disease as part of multi-modality treatment.
More wound complications but reduced fibrosis and reduced field and dose.
Myxoid liposarcoma - v. radiosensitive, more likely to use NAdjRT.

50Gy/25#/5 weeks
CTV = GTV + 2 radially + 3cm sup/inf.
PTV = +5-10 depending on immobilisation.

Question 3

Definitive RT STS?
Indications, dose/#.

Answer 3

If inoperable.
66Gy/33#/6.5 weeks

Question 4

Palliative radiotherapy sarcoma?
1L SACT.

Answer 4

Can offer higher dose palliative schedules due to relative “radioresistance”.
36Gy/6#/6weeks.
36Gy/12#/2.5 weeks
45Gy/15#/3 weeks

i.e. bladder, lung and H+N doses.

1L SACT
Doxo or ifos - occassionally together if young, fit, extensive disease
Alternative cylophos and pred - good in elderly.
2L = alternative of doxo or ifos. Gem and docetaxel,dacarbazine, trabectidin.

Don’t forget SABR for upto 3 lung mets.

Question 5

Summary management for Osteosarcoma, RMS and Ewing’s?

Answer 5

All except low grade osteo or unresectable osteo.
For induction chemo.
Definitive treatment - surgery +/- RT
Then adjuvant chemo.

RMS/Ewing’s +/- extra RT to lung/abdo.
Osteo +/- metastaectomy (lung).

Question 6

Definite RT in chordoma, chondrosarcoma or osteosarcoma?
Indication, dose/#.

Answer 6

Definitive RT in unresectable disease.
Chordoma - often unresectable
75.6Gy/42#/8.5 weeks delivered with protons.

Question 6

Adjuvant RT in chordoma, chondrosarcoma or osteosarcoma?
Indication, dose/#.

Answer 6

Adjuvant RT chordoma - if high risk of local relapse and limited option for further surgery. 70.2Gy/39-75.6Gy/42#/8.5 weeks delivered with protons.

Chondro/OsteosarcomaAdjuvant RT
Limb: 60-66Gy/30-33#/6-6.5weeks depending on margins.
Pelvis/spine: 68.4/38#-75.6Gy/42#/8.5 weeks

Question 7

Mx of Ewing’s sarcoma.
Including RT dose/#

Answer 7

Chemoreduction,
Definitive treatment = surgery +/- NeoAdj RT if marginal resection expected +/- Adjuvant RT. Or definitive RT.
Then adjuvant chemo.
+/-adjuvant lung RT.

Neo-adj 50.4Gy/28#/5.5weeks
Adj or definitive 54Gy/30#/6weeks.
Whole lung RT: If CR or near CR.
<14 years of age: 15 Gy in 10 fractions over 2 weeks
>/=14 years of age:18 Gy in 12 fractions over 2.5 weeks

Volumes: CTV = +2cm isotropically

Question 8

Rhabdomyosarcoma Mx.
Including RT dose/#

Answer 8

Chemoreduction,
Definitive treatment = surgery +/- NeoAdj RT if marginal resection expected +/- Adjuvant RT. Or definitive RT.
Then adjuvant chemo.
+/-adjuvant lung RT +/- whole abdo RT.

Neo-adj 41.4Gy/23#/4.5 weeks
Adj/definitive 50.4Gy/28#/5.5weeks- note for definitive RT to all mets in adults in favourable (PAX-FOX01 negative) only.
Whole abdo RT if ascites or diffuse periotoneal disease 24Gy/16#/daily
Whole lung RT - kids only, 15Gy/10#/2weeks

Question 9

Summary of indications and doses for whole abdo RT?

Answer 9

Both indicated if have lots of abdo disease.

Wilm’s: If have disseminated abdominal disease or gross per- or peri-operative rupture.
Intermediate risk 15Gy/10#/12 weeks.
High risk 25.2Gy/14#/3weeks

RMS: If ascites or diffuse periotoneal disease.
24Gy/16#/daily

Question 10

Summary of indications for whole lung RT?
Dose/#.

Answer 10

Wilm’s - If don’t achieve CR.
int risk: 12Gy/8#/1.5 weeks.
High risk 15Gy/10#/12weeks.
<1yr for lower dose/#.

RMS - kids only (? adults also if favourable as “definitive RT to all mets”)
15Gy/10#/2 weeks.

Ewing’s - Whole lung RT If CR or near CR.
<14 years of age: 15 Gy in 10 fractions over 2 weeks
>/=14 years of age:18 Gy in 12 fractions over 2.5 weeks