Intensiteitsgemoduleerde Radiotherapie (IMRT) - KCE

32 Intensity-modulated radiotherapy KCE reports 62
time spent by medical physicists, will increase drastically. Two surveys 83 84 carried out
in the USA for the years 2001 and 2003 confirm this. Both surveys were conducted by
the American Association of Physicists in Medicine (AAPM) Professional Council and
the American College of Medical Physics (ACMP). The survey carried out by Herman in
2003 was based on the output of thirty completed surveys sent out to medical physics
departments and groups in 2001. The survey carried out by Mills in 2005 (the “Abt
survey”) was based on surveys sent to 100 qualified medical physicists (QMP) in 2005,
chosen to reflect overall practice type and geographic location for the QMP profession.
Consequently, the design of the Abt survey is superior to that of the Herman survey.
Both surveys drew on procedure descriptions applying to Medicare billing codes.
As illustrated by Table 6 physics time for IMRT compared to 3DCRT increases by a
factor of around 3. This increase in time spent by a physicist will only in part be offset
by a decrease in support staff time c (see Table 7).
Table 6 Physics Time for 3DCRT and IMRT
Herman Survey Abt Survey
Procedure Description Physicist Hours per Patient
IMRT Treatment Planning 12,03 10
Therapeutic radiology simulation-aided field setting,
3-dimensional 3,51 3,75
Relative Impact IMRT versus 3DCRT 3,4 2,7
Table 7 Physics Support Staff Time for 3DCRT and IMRT
Procedure Description 2003 Abt Survey Support Staff Estimates (Hours)
IMRT Treatment Planning
Therapeutic radiology simulation-aided
3
field setting, 3-dimensional 3,75
Relative Impact IMRT versus 3DCRT 0,8
Since the main and methodologically most compelling source comparing treatment
preparation times between 3DCRT and IMRT applies to time spent by American
physicists and “physics support staff”, we have no reliable means at present to assess to
which extent these findings apply to physics time spent by Belgian professionals, nor to
time spent by related categories of (para)medical health professionals involved in the
preparation, delivery and follow-up of IMRT in a specifically Belgian context.
Through our grey search we found a single-centre comparison made between planning
times for 3DCRT and IMRT treatment of respectively prostate and Head and Neck
cancer 85 . These figures (Table 8) indicate that the average planning times vary more by
radiated tumour site (irrespective of the chosen technique) than they do between
techniques (irrespective of tumour site).
c Mills 2005 defines physics support staff as “medical dosimetrists, physics assistants, equipment engineers,
physics technologists, physics residents and so on”