TY - JOUR T1 - Acute Toxicity in Hypofractionated/Stereotactic Prostate Radiotherapy of Elderly Patients: Use of the Image-guided Radio Therapy (IGRT) Clarity System JF - In Vivo JO - In Vivo SP - 1849 LP - 1856 DO - 10.21873/invivo.12447 VL - 35 IS - 3 AU - ROSSELLA DI FRANCO AU - VALENTINA BORZILLO AU - DOMINGO ALBERTI AU - GIANLUCA AMETRANO AU - ANGELA PETITO AU - ANDREA COPPOLARO AU - ILARIA TARANTINO AU - SABRINA ROSSETTI AU - SANDRO PIGNATA AU - GELSOMINA IOVANE AU - SISTO PERDONÀ AU - GIUSEPPE QUARTO AU - GIOVANNI GRIMALDI AU - ALESSANDRO IZZO AU - LUIGI CASTALDO AU - RAFFAELE MUSCARIELLO AU - MARCELLO SERRA AU - GAETANO FACCHINI AU - PAOLO MUTO Y1 - 2021/05/01 UR - http://iv.iiarjournals.org/content/35/3/1849.abstract N2 - Background: The use of intra-fractional monitoring and correction of prostate position with the Image Guided Radio Therapy (IGRT) system can increase the spatial accuracy of dose delivery. Clarity is a system used for intrafraction prostate-motion management, it provides a real-time visualization of prostate with a transperineal ultrasound. The aim of this study was to evaluate the use of Clarity-IGRT on proper intrafraction alignment and monitoring, its impact on Planning Tumor Volume margin and on urinary and rectal toxicity in elderly patients not eligible for surgery. Patients and Methods: Twenty-five elderly prostate cancer patients, median age=75 years (range=75-90 years) were treated with Volumetric Radiotherapy and Clarity-IGRT using 3 different schemes: A) 64.5/72 Gray (Gy) in 30 fractions on prostate and seminal vesicles (6 patients); B) 35 Gy in 5 fractions on prostate and seminal vesicles (12 patients); C): 35 Gy in 5 fractions on prostate (7 patients). Ultrasound identification of the overlapped structures to the detected ones during simulation has been used in each session. A specific software calculates direction and entity of necessary shift to obtain the perfect match. The average misalignment in the three-dimensional space has been determined and shown in a box-plot. Results: All patients completed treatment with mild-moderate toxicity. During treatment, genitourinary toxicity was 32% Grade 1; 4% Grade 2, rectal was 4% Grade 1. At follow-up of 3 months, genitourinary toxicity was 20% Grade 1; 4% Grade 2, rectal toxicity was 4% Grade 2. At follow-up of 6 months, genitourinary toxicity was 4% Grade 1; 4% Grade 2. Rectal toxicity was 4% Grade 2. Conclusion: Radiotherapy with the Clarity System allows a reduction of PTV margins, the amount of fractions can be reduced increasing the total dose, not exacerbating urinary and rectal toxicity with greater patient’s compliance. ER -