ESTRO 2024 - Abstract Book

S2570

Clinical - Urology

ESTRO 2024

Material/Methods:

Patients treated with SBRT of 42Gy, 7Gy per fraction over the prostate and seminal vesicles volume with a margin of 4mm were prospectively followed up to the present day. The planning CT was performed after rectal preparation and dietary recommendations, with diuresis control, immobilisation with a wedge under the knees and abdominal compressor.

Intensity modulated radiotherapy was applied using a Linear Electron Accelerator with a photon beam energy of 6MV using image guided radiotherapy with Cone-Beam CT every single day.

Follow-up was performed weekly during treatment, at one month, three months and every six months after treatment. Observed toxicities were analysed using the CTCAE v.5.0 scale.

Results:

74 patients with a mean age of 72,01 years were treated. A total of 87,84% received hormonal treatment. There were 8 patients who, due to different comorbidities, did not receive hormone treatment.

With a median follow-up of 25,95 months both PFS and CSS is 100% with an OS of 97,3%.

Acute urinary toxicity G1 (polyuria, nycturia and dysuria) was observed in 54,05% and G2 in 9,46%. Two patients had G3. G1 acute gastrointestinal toxicity occurred in 18,92% and 1,35% G2. Beyond 6 months, G1 urinary toxicities were reported in 2.7% and 1,35% G2. 1 patient developed acute urinary retention resulting in transurethral resection and there were 3 cases of actinic proctitis requiring argon laser coagulation.

Conclusion:

42Gy SBRT in unfavourable intermediate localised prostate cancer is an alternative with an acceptable toxicity profile, and excellent disease control within the first 2 years. Further follow-up is needed to confirm these results.

Keywords: Prostate Cancer, Radiotherapy, SBRT

References:

1- Fransson P, Nilsson P, Gunnlaugsson A, Beckman L, Tavelin B, Norman D, Thellenberg-Karlsson C, Hoyer M, Lagerlund M, Kindblom J, Ginman C, Johansson B, Björnlinger K, Seke M, Agrup M, Zackrisson B, Kjellén E, Franzén L, Widmark A. Ultra-hypofractionated versus conventionally fractionated radiotherapy for prostate cancer (HYPO-RT PC): patient-reported quality-of-life outcomes of a randomised, controlled, non-inferiority, phase 3 trial. Lancet Oncol. 2021 Feb;22(2):235-245. 2- Andruska N, Fischer-Valuck BW, Agabalogun T, Carmona R, Brenneman RJ, Huang Y, Gay HA, Michalski JM, Baumann BC. Propensity-Weighted Survival Analysis of SBRT vs. Conventional Radiotherapy in Unfavorable Intermediate-Risk Prostate Cancer. Clin Genitourin Cancer. 2022 Apr;20(2):123-131.