ESTRO 2024 - Abstract Book

S2499

Clinical - Urology

ESTRO 2024

We found 20 (57%) macrosopic relapses, all but 3 (9%) subject to ablative fractionated stereotactic radiotherapy (FSRT) by image registration for MRI-guided dose painting, 3 (9%) with concurrent nodal FSRT for synchronous oligo recurrence. Prostate-bed target volume delineation and PET/MRI-guided in-bed lesion simultaneous integrated boost (SIB) was performed in 1 (3%) of the remaining, due to irrespective healthy tissues dose constraints harboring unacceptable FSRT toxicity risk; exclusive androgen-deprivation therapy (ADT) in 2 (6%) cases for older age and high obstructive risk. Pelvic nodal, and bone oligo-recurrence only were detected in 5 (14%) and 2 (6%) patients, respectively: we chose metastases-directed FSRT without prostate-bed irradiation plus concurrent ADT for 5 (14%) of them, ADT and SRT plus positive node SIB and elective node irradiation for 2 (6%) 65-year-old patients. Eight (23%) patients had both negative NGI, thus standard SRT was performed except for 3 (9%) (refusing), for whom close PSA monitoring was applied. Changing therapeutic approach beyond the standard of care was reported in 27 (77%) of cases (Figure 1).

Conclusion:

Advances in imaging and radiotherapy planning and delivery techniques enabled precision radiation oncology and allowed us to set NGI-targeted, patient-tailored salvage treatments, possibly with curative intent, or to achieve long term prostate cancer disease control. Longer follow up is needed to better understand the efficacy and safety of our promising findings. Prospective validation of our results, including all prostate cancer patients with BCR after primary treatment (RP or RT) in the same observation time, is ongoing and is expected to further clarify the true impact of NGI to maximize the therapeutic potential of radiation and inform radiation decisions.

Keywords: next-generation imaging, stereotactic radiotherapy

2148

Digital Poster

Hypofractionated chemoradiotherapy for bladder preservation in muscle-invasive bladder cancer