ESTRO 2022 - Abstract Book

S1245

Abstract book

ESTRO 2022

Conclusion Temperature measurement procedures, such as rate of acquisition, seem to influence the predictive role of temperatures, i.e., its reliability as treatment quality descriptors.

PO-1466 On how treatment over weekends palliate scheduled and unscheduled interruptions.

E.M. AMBROA REY 1 , T. Valdivielso 1 , J. García-Miguel 1 , M. Lizondo 1 , T. Ramírez 1 , Á. Infestas 1 , D. Navarro 1 , Á. Lorenzo 1 , M. Parcerisa 1 , R. Pujol 1 , Ú. Gallardo 1 , A. Peralta 1 , A. López 1 , D. Amat 1 , G. Frontera 1 , M. Colomer 1

1 Consorci Sanitari de Terrassa, Medical Physics Unit, Radiation Oncology Department, Terrasa (Barcelona), Spain

Purpose or Objective To manage interruptions in radiotherapy treatments and avoid the prolongation of overall treatment time (OTT), treatments during the weekends were introduced in 2019. We have performed a comparison with the previous year (2018) to analyze the differences in terms of treatment delays. Materials and Methods Treatments on Saturdays were added if during the week a scheduled (machine preventive maintenance or public holiday) or unscheduled interruption (machine breakdown) was present. We used a system based on categories to prioritize treatments and decide which patients were treated on Saturdays. We have compared the OTT and days of delay for 844 patients treated in 2018 and 890 treated in 2019. Results Mean overall treatment delay was 4.5 days (4 days median value) during 2018 and 3.4 days during 2019 (3 days median value). This means a reduction of 25.8%. In addition, a classification into intervals (0-2, 3-5, 6-10, and more than 10 days), according to the delay, was performed for a deeper analysis. Figure 1 shows the percentage of patients regarding the delay interval per year.

Figure 1. Delay intervals for each year.

In total, there is a 12% reduction in the ‘0-2 day interval’, a 7% reduction in the ‘6-10 day interval’, and a 3% reduction for ‘> 10 days’ interval. In addition, during 2019, 5% of the treatments were completed before the estimated finish date (between 1 to 3 days earlier). If we look at treatment delay for pathology (Table 1), the OTT was reduced by 62% for rectum treatments, 38% for H&N, 35% for esophagus, 31% for gynecological, 31% for lung, and 18% for breast. Treatments with higher priorities had a higher reduction in the OTT in most cases.

Localization

2018 Delay (days)

2019 Delay (days)

OTT Reduction

H&N

8.0 5.4

5.0 3.7 0.3 2.0 3.4 3.6 4.3

38% 31%

Gynecological

SBRT

0

Same

Rectum

5.3 4.9 5.5 5.0

62% 31% 35% 14%

Lung

Esophagus

CNS