Micropos Medical Ab · NGM:MPOS
Micropos Medical Ab — ESTRO 2024
35 slides from Micropos Medical Ab's conference presentation, May 2024
Slide 1: Urethra-Sparing Single-Dose Ablative Prostate Radiotherapy With Real-Time Motion Management
Urethra-Sparing Single-Dose Ablative Prostate Radiotherapy With Real-Time Motion Management Dr. Valeria Faccenda Medical Physics Department – Fondazione IRCCS San Gerardo dei Tintori, Monza (Italy) valeria.faccenda@irccs-sangerardo.it valefacc22@gmail.com valefacc22 valeria-faccenda
Slide 2: Background
Background ▪ Along with huge improvement in radiobiological knowledge and technical capabilities, in recent years extreme hypofractionation using SBRT has been explored with optimal results in terms of biochemical control and side effects for patients with localized PCa.
Slide 3: Background
Background ▪ Along with huge improvement in radiobiological knowledge and technical capabilities, in recent years extreme hypofractionation using SBRT has been explored with optimal results in terms of biochemical control and side effects for patients with localized PCa. SBRT: new standard of care i
Slide 4: Background: Less number of fractions?
Background 1. Less number of fractions?
Slide 5: Background
Background 1. Less number of fractions? - 2SMART - HERMES
Slide 6: Background
Background 45 patients 19 Gy in one fraction Low-intermediate risk PCa 18 months FUP 30 patients 24 Gy in one fraction Intermediate risk PCa 48 months FUP
Slide 7: Background
Background ▪ The enthusiasm for the development of single-fraction regimens must be weighted against data from the HDR brachytherapy experience, where single-session treatments have shown disappointing results in terms of biochemical relapse free survival rates with 19 – 21 Gy. – 21Gy1f Local failur
Slide 8: Background
Background • Single dose radiotherapy engages synthetic cell-kill pathway through microvascular dysfunction synergizing double-strand DNA damage misrepair • Published clinical evidences [Greco et al. IJROBP 2019; Zelefsky et al. IJROBP 2021] show that the dose of 24 Gy provides unprecedented long-te
Slide 9: Background: High-risk prostate cancer?
Background 2. High-risk prostate cancer?
Slide 10: Background
Background 2. High-risk prostate cancer? HYPO-RT 11% of HR PCa patients Waiting for PACE-C trial
Slide 11: Background
Background • The combination of ADT with RT has been shown to improve overall survival for patients with intermediate- and high-risk Pca • Inferior biochemical control rates of about 70-90% at 5-years [eg. PROSINT: 77.1% for unfavorable intermediate and 100% for favorable intermediate with no ADT ad
Slide 12: Purpose
Purpose ▪ ABRUPT TRIAL (NCT04831983): Single-Dose Ablative Radiation Therapy (SDART) of 24 Gy (BED1.5 = 408Gy) for Unfavorable intermediate or selected high-risk Prostate Tumors • ADT PRIMARY ENDPOINT: • Urethra sparing Cumulative incidence of acute and late GU • Real-time intrafraction organ motion
Slide 13: Population
Population ▪ 30 patients from June 2021 Inclusion Criteria: 1. Histologic confirmation of adenocarcinoma by biopsy 2. No direct evidence of regional or distant metastases after appropriate staging studies 3. No previous local treatment of the prostate with surgery or previous RT to the pelvis 4. CT
Slide 14: Patient setup
Patient setup • Simulation CT: Foley catheter to fill the bladder with 150cc of salin solution and urethra localization and rectal microenema to ensure the emptying of the rectum
Slide 15: Patient setup
Patient setup • Simulation mpMRI: Same bladder and bowel preparation to properly delineate the target volume and the OARs
Slide 16: Patient setup
Patient setup • Simulation mpMRI: Same bladder and bowel preparation to properly delineate the target volume and the OARs CTV (cm3) PTV (cm3) Median (range) 50.8 (16.3 – 75.7) Median (range) 72.0 (25.6 – 100.6) PTV = CTV (prostate gland + seminal vesicles) + 2 mm
Slide 17: Treatment Planning
Treatment Planning ▪ Linac-based: 10MV FFF single partial arc (from 140° to 220°). ▪ A high-dose avoidance zone (HDAZ) was created by a 3 mm expansion around the rectum, bladder, and urethra. ▪ The target minimum dose was defined by the OARs dose constraints, with a dose escalation in the volume awa
Slide 18: Treatment Planning
‘Ss 3-7 May 2024 ES TRO Glasgow, UK | 2024 Treatment Planning
Slide 19: Plan goals and statistics
Plan goals and statistics median mean range objective Urethra PRV D0.035cc (Gy) 20.9 20.9 20.1 - 21.8 ≤ 22.8 D1cc (Gy) 19.1 19.0 18.2 - 19.2 ≤ 19.2 EQD23 = 85.2 Gy Bladder PRV D0.035cc (Gy) 23.7 23.7 23.4 - 24.0 ≤ 24 D1cc (Gy) 22.6 22.6 21.9 - 22.8 ≤ 22.8 D50% (Gy) 4.1 4.0 1.3 - 10.0 ≤ 12 Rectum PRV
Slide 20: Plan characteristics
Plan characteristics # MU Mean (SD) 6910 (592) Median (range) 6977 (5522 – 7753) Delivery time (min) Mean (SD) 4.4 (0.5) Median (range) 4.3 (3.3 – 5.7)
Slide 21: Organ motion management (1)
Organ motion management (1) A) Balloon in bladder B) RayPilot transmitter C) Connector D) Standard urine out lumen E) Valve for balloon placed directly on the existing carbon fiber couch
Slide 22: Patient setup
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Slide 23: Patient setup
‘ 3-7 May 2024 ES TRO Glasgow, UK | 2024 Patient setup Planning CT cBCT Foley catheter catheter + transmitter “(_a67__ = os a
Slide 24: Organ motion management (2)
Organ motion management (2) BEAM INTERRUPTION Non re-entering motion > 2 mm? Real Time Tracking patients yes no 2 mm repositioned threshold by new CBCT
Slide 25: Intrafraction prostate motion
Intrafraction prostate motion 10/30 (33%) 20/30 (67%) no intervention needed motion >2mm detected 2.1 interventions [range 1 – 7] per patient on average Control of intrafraction motion is mandatory in order to ensure to always irradiate the target according to the plan, and to minimize the dose to r
Slide 26: Intrafraction prostate motion
Intrafraction prostate motion Prostate motion analysis Setup Delivery Treatment Time spent outside the 2 mm threshold 23% 7% 18% Treatment duration Total treatment time (min) Mean (SD) 15.9 (8.4) Median (range) 14.0 (6.9 – 35.5)
Slide 27: Treatment outcomes
Treatment outcomes Median FUP = 18 months [range 6 – 31] ▪ Within 3 months post-treatment, there was one instance of G1 acute GI toxicity, while 8 cases (26.7%) of acute GU toxicity were observed. Among these, two patients (6.7%) had G2 urinary toxicity ▪ The incidence of late GI and GU toxicity was
Slide 28: Conclusions
Conclusions ▪ 24 Gy single-dose ablative radiation therapy irradiation of the whole prostate was feasible and well-tolerated: only 3 instances of G2 GU and GI toxicities at a median FUP of 18 months. ▪ The use of appropriate imaging procedures, negative dose-painting during planning and mandatory on
Slide 29: Conclusions
Conclusions ▪ 24 Gy single-dose ablative radiation therapy irradiation of the whole prostate was feasible and well-tolerated: only 3 instances of G2 GU and GI toxicities at a median FUP of 18 months. ▪ The use of appropriate imaging procedures, negative dose-painting during planning and mandatory on
Slide 30: Thanks for your attention!
Acknowledgments Prof. Stefano Arcangeli Dr. Denis Panizza Thanks for your Dr. Elena De Ponti, Dr. Martina Daniotti, attention! Dr. Raffaella Lucchini, Dr. Maria Belmonte, Dr. Giorgio Purrello, Dr. Federica Ferrario, Dr. Chiara Chissotti valeria.faccenda@irccs-sangerardo.it valefacc22@gmail.com valef
Slide 31: Glasgow, UK
> — ae Glasgow, UK
Slide 32: Treatment Outcomes
Treatment Outcomes Acute Late Adverse event Grade 1 Grade 2 Grade ≥3 Grade 1 Grade 2 Grade ≥3 (CTCAEv.5.0) Genitourinary N (%) N (%) N (%) N (%) N (%) N (%) Urinary incontinence – – – – 2 (6.7) – Urinary frequency 1 (3.3) 1 (3.3) – 4 (13.3) 1 (3.3) – Urinary urgency 5 (16.7) 2 (6.7) – 6 (20) 2 (6.7)
Slide 33: Purpose
Purpose ▪ 30 patients with organ-confined (T2-T3aN0M0) unfavorable intermediate or selected high-risk prostate tumors according to NCCN guidelines (from June 2021) Parameter No. Median age [range] 77 [62 – 84] Median PSA [range] 8.04 [3.41 – 18.27] Gleason Score 7 (4+3) 10 (33%) 8 (4+4) 16 (53.5%) 8
Slide 34: Background
Background ▪ In the ONE-SHOT phase I/II trial (NCT03294889), 45 patients recruited in 5 centers between 2017 and 2022 received a single fraction of 19 Gy to the prostate, with 17 Gy dose-reduction to the urethra. ▪ Good toxicity profile: two-phase GU toxicity flare, a first one during the first week
Slide 35: Background
Background ▪ The PROSINT phase II trial (NCT02570919) randomized 30 patients with intermediate- risk prostate cancer to receive 45 Gy in five fractions or 24 Gy in one fraction. No androgen deprivation therapy was allowed. ▪ Comparable toxicity profile: time to appearance and duration of late GU and