Department of Radiation Oncology
Fully automated treatment plan generation in daily routine
Heijmen B, Voet P, Dirkx M, Sharfo A, Rossi L, Fransen D, Penninkhof J,
Hoogeman M, Petit S, Mens JW, Méndez Romero A, Al-Mamgani A,
Incrocci L, Breedveld S.
8 th European Conference on Medical Physics, Athens, 2014

Current treatment planning : an iterative trial-and-error procedure in which the dosimetrist tries to steer the TPS towards an acceptable plan by tweaking of parameters, such as objectives or weights
Issues
 Plan quality is strongly dependent on skills and experience of the dosimetrist (operator dependence).
 Plan quality is dependent on allotted time.
 Difficult to decide when to stop; could more time result in a better plan?
 Plan generation often based on templates (non-individualized)
 Plan generation may take from 30 min. up to many hours
 Due to involved workload, planning is costly
An alternative: Automated Treatment Planning with
Erasmus-iCycle/Monaco

Erasmus-iCycle: Med Phys. 2012; 39(2): 951-963.
Monaco: Elekta AB, Stockholm, Sweden

hard
Prostate wishlist

For each treatment site the wishlist is a priori established iterative procedure of
Erasmus-iCycle plan generations/evaluations, followed by wishlist updates
Institutions can generate their own wishlists

 under the hood: lexicographic, multi-criterial optimization in
Erasmus-iCycle, using priorities of objective functions as defined in the wishlist
 Erasmus-iCycle optimizes fluences, Monaco takes care of segmentation
 planning is fully automatic (‘push button system’, no tweaking)  huge reduction in planning workload and result is operator independent
 works for IMRT and VMAT, IMRT plans are Pareto optimal
 for IMRT Erasmus-iCycle has automated selection of beam angles
(coplanar and non-coplanar beam arrangements)

Int J Radiat Oncol Biol Phys. 2013; 85(3): 866-72.

Study design
• On average 1 in 5 patients got an automatic plan next to the regular clinical plan made by dosimetrists
• Dosimetrists and treating physicians didn’t know whether or not there would be an automatic plan.
• All plans were coplanar and had a maximum of 9 beams.
• Treating radiation oncologist selected the plan for treatment
Study results
• in 32/33 cases automatic plan was selected by physician
(almost always better sparing, often also better tumor coverage)
• also objectively (DVHs, NTCP) automatic plans had higher quality.

differences between automatic and manual planning in mean OAR doses

Study design
30 previously treated prostate cancer patients (78 Gy, IMRT/IGRT)
Compare
VMAT plan, automatically generated with Erasmus-iCycle/Monaco with
1. IMRT plan, manually generated with Monaco in clinical routine, and actually delivered
2. VMAT plan, manually generated with Monaco by expert planner in absence of time pressure

VMAT automatic vs.
IMRT manual clinical

VMAT automatic vs.
VMAT manual expert planner no time pressure

Conclusions for prostate cancer
With automated planning:
- Higher plan quality than in clinical routine
- No loss in plan quality compared to an expert planner in absence of time constraints (non-clinical condition)
ALWAYS : vast reduction in workload

Conclusions
 Compared to ‘manual’ planning, automated planning with
ErasmusiCycle/Monaco
 has higher or non-inferior plan quality
 plan quality is not operator dependent
 plan quality is not dependent on allotted time in a busy clinic
 has negligible workload
 Automated planning is currently in clinical use for prostate cancer, head-and-neck cancer, and cervical cancer.
Next step
International validation study of automated planning with
Erasmus-iCycle/Monaco, together with Florence, Leeds, Mannheim,
Vienna, and Elekta AB.