ESTRO 2024 - Abstract Book

S1809

Clinical - Lung

ESTRO 2024

Results:

The BgRT plan had a 28% smaller PTV (18.1 cc) compared to the linac-based plan (25.2 cc). The patient successfully completed four BgRT treatments over six days. On average, the time from the FDG tracer injection to PET imaging was 78.2 minutes, included 45-60 mins of FDG uptake, patient setup and kVCT localization on X1. Beam-on-time for the BgRT delivery was 27.8 ± 0.4 minutes, while the patient was on the table for 59.8 ± 9.5 mins. The average AC and NTS from the PET planning through to treatment was 23.3 ± 1.3 kBq/ml and 11.1 ± 1.8, respectively. Both BgRT and conventional SABR plans met institutional dosimetric constraints. Post-treatment dose reconstruction of the delivered BgRT sessions showed about 1.5 % increase in planned vs delivered mean dose to PTV and GTV (Figure 2) while the OAR doses were similar. The treatment was well tolerated with no adverse events noted for BgRT delivery or FDG injections.

Figure 2:DVH of BgRT planned and delivered doses for all 4 fractions. Triangles are delivered, and dotted lines are planned BgRT.