Common Doses (and dose/#) Flashcards
Dose for gastric and gastroesophageal adenocarcinoma adjuvant EBRT chemoradiation:
Bonus if you can guess the chemo
If:
1) Stage:
T3 N+ OR T3 N0 with positive margins OR
T4 OR N+
ECOG 0-2
2) Adequate nutritional intake
3) Suitable for combined therapy
45/25 (INT Trial) + consider 5.4Gy/3# boost to GTV if can be visualised.
Notify surgeon if both ends of anastomosis likely to be in field.
MAGIC (Epirubicin-Cisplatin-5FU), updated to FLOT-4 (5FU-leucovorin-oxaliplatin-docetaxel)
Thyroid RAI doses
ESMO guidelines (US tend to be less):
Adjuvant = 100mCi
micro residual = 150mCi
Metastatic = 200mCi
Retreatment can be considered up to cumulative 600mCi
Dose EBRT for thyroid cancer and indications:
60-70Gy 1.8-2Gy/#
It is optimally used in a small subset of pts w/aggressive locoregional disease.
A single randomized prospective trial failed to recruit adequate patients and only 26 received EBRT. However, a mounting retrospective data showing significant benefit for EBRT in select patients: with gross residual or unresectable locoregional disease, except for patients <45 years old with limited gross disease that is RAI-avid.
High risk prostate cancer: Definitive Brachy + EBRT dose:
Urinary function requirements?
Definitive radiotherapy:
HDR brachytherapy boost, 15Gy/1#
and
46Gy/23# EBRT
and ADT 18-36months (typically 2 years)
HDR brachytherapy can be given before, concurrent with or after the external beam radiation therapy.
The optimal dose, fractionation and brachytherapy scheduling has yet to be defined.
IPSS < 15. If IPSS > 15, then formal flow studies
Caution:
Peak urinary flow r< 15 mL/sec or post void residual > 100 mL
Dose for SABR to spine met (e.g. prostate).
24Gy/2 fractions (there are a very wide range including 27/3)
For Int Prostate Cancer: Conventional dose vs Hypo#
Evidence for Hypo# dose?
78Gy/39#
vs
60Gy/20#
60gy/20# supported by multiple Phase III trials: PROFIT, CHHiP, RTOG - these demonstrate non-inferiority (either with or without ADT, low or intermediate risk) and 2 studies demonstate no increased bladder or bowel toxity, one suggests more grd II/III late toxiciy.
Extensive stage SCLC dose?
Trial?
IF: Any response to systemic therapy and residual thoracic disease.
Limited extra-thoracic metastatic disease burden.
Consolidative dose: 30Gy/10#
CREST Trial:
CTRT improved 2-year overall survival (13% vs 3%) and 6-month progression free survival.
Limited stage SCLC dose?
Ideally concurrent with?
The alternative approach:
Give a little Hx of this dose:
(Concurrent chemotherapy is preferred - ideally with earlier cycles of chemotherapy)
Currently 40Gy/15# with dose escalation to higher doses (50/25 or 66/33) where possible.
Hyperfractionated 45/30 BD.
Early trials demonstrated an OS benefit w/RT, subsequently confirmed on meta-analysis.
Turrisi 1999 - 45Gy/25# (1.8Gy/#) vs 45Gy BID (1.5Gy/#) (!!!These doses are not BED equivalent!!!) w/concurrent cisplatin etop
CONVERT trial suggests BID !!45/25!! may still be superior to 66Gy in 33 once-daily fractions (2Gy over 45 days). Favouring better median OS in BID group.
Limited stage Small cell lung cancer PCI dose:
Japanese RCT suggests for extensive stage pts PCI can be omitted in favour of close (3monthly MR) surveillance - original data suggesting benefit defined no cranial disease on CT (not MR) therefore a number of pts who truly had brain mets were included..
Complete responders: 25Gy/5#
Partial responders: 20Gy/5#s
Doses “partly” supported by metaanalysis. Original data (1999) supported OS benefit. RCT data suggests 25/5 as effective as 36/18…
Extensive stage Small cell lung cancer PCI dose:
20/5 or 25/5 both employed. RCT data = Slotman 2007 - better OS and less symptomatic brain mets at 1 year.
Japanese RCT suggests for extensive stage pts PCI can be omitted in favour of close (3monthly MR) surveillance - original data suggesting benefit defined no cranial disease on CT (not MR) therefore a number of pts who truly had brain mets were included..
Dose: Oligo mets to lung?
Criteria?
All evidence is at best phase II
Oligometastatic/oligoprogressive/oligopersistent peripherally located (defined as at least 2 cm from the bifurcation of the lobar bronchi) lung metastases (0-3 metastases).
Tumour/s ≤5 cm in maximum diameter.
Supported by Phase II data:
30/1 or 54/3 - away from chest wall/not central
(phase II study, efficacy of a 30 Gy single fraction was found to have lower 2-year LC compared to multi-fraction SABR (74% vs 91% respectively).
48/4 within 1cm of chest wall - Saffron II TROG (phase II) suggests 48/4 not inferior to 30/1.
Indication for SABR for NSCLC and dose:
Target volume objectives!!!????!!
1) Stage I-IIa non small cell lung cancer (NSCLC).
2) Tumour ≤5 cm in maximum diameter.
3) Peripherally located tumour defined as at least 2 cm from the bifurcation of the lobar bronchi.6
4) Medically inoperable or declining surgery.
IF tumour GTV <1 cm from chest wall, consider 48 Gy in 4 fractions (12 Gy/fx).
54/3 or 30/1
Target volume objectives!!!
D95-99% ≥100% of PD.
Non-small cell lung cancer stereotactic EBRT central tumours?
Define central:
Define Ultra-Central:
Target volume objectives!!!????!!
For 1-2 (≤5 cm maximum diameter) N0 M0 non-small cell lung cancer (NSCLC). Centrally located tumour defined as ≤2 cm around the proximal bronchial tree (PBT) - NB not “ultra central”
Ultracentral defined as: PTV touching or overlapping the central bronchial tree, oesophagus, pulmonary vein, or pulmonary artery.
Dose 50/5
iGTV should get DMax 125-143% of PD.
PTV should get D95-99% ≥100% of PD.
NSCLC adj dose:
Its a bit of a trick: A meta-analysis demonstrates no clear evidence of an adverse or beneficial effect of PORT on survival in patients with pN2 disease. The applicability of this finding to current day practice is questionable. Data from four non-randomised studies suggest a survival benefit for PORT in pN2 disease.
N2 = mets in ipsilateral mediastinal/subcarinal nodes
N2 [R0] disease - 50/25
N2 R1 - 54/27
N2 R2 60/30
The non-SABR NSCLC curative intent dose:
Evidence?
60/30
Bradley (RCT) Trial 2015: for stage III dose escalation to 74Gy not supported. Better survival in 60gy arm
For node negative patients not suitable for SABR consider dose escalation e.g. 66Gy/33# or moderate hypofractionation
