TY - JOUR A1 - Zimmermann, Marcus A1 - Richter, Anne A1 - Weick, Stefan A1 - Exner, Florian A1 - Mantel, Frederick A1 - Diefenhardt, Markus A1 - Fokas, Emmanouil A1 - Kosmala, Rebekka A1 - Flentje, Michael A1 - Polat, Bülent T1 - Acute toxicities of patients with locally advanced rectal cancer treated with intensified chemoradiotherapy within the CAO/ARO/AIO-12 trial: comparing conventional versus VMAT planning at a single center JF - Scientific Reports N2 - In locally advanced rectal cancer (LARC) neoadjuvant chemoradiotherapy is regarded as standard treatment. We assessed acute toxicities in patients receiving conventional 3D-conformal radiotherapy (3D-RT) and correlated them with dosimetric parameters after re-planning with volumetric modulated arc therapy (VMAT). Patients were randomized within the multicenter CAO/ARO/AIO-12 trial and received 50.4 Gy in 28 fractions and simultaneous chemotherapy with fluorouracil and oxaliplatin. Organs at risk (OAR) were contoured in a standardized approach. Acute toxicities and dose volume histogram parameters of 3D-RT plans were compared to retrospectively calculated VMAT plans. From 08/2015 to 01/2018, 35 patients with LARC were treated at one study center. Thirty-four patients were analyzed of whom 1 (3%) was UICC stage II and 33 (97%) patients were UICC stage III. Grade 3 acute toxicities occurred in 5 patients (15%). Patients with acute grade 1 cystitis (n = 9) had significantly higher D\(_{mean}\) values for bladder (29.4 Gy vs. 25.2 Gy, p < 0.01) compared to patients without bladder toxicities. Acute diarrhea was associated with small bowel volume (grade 2: 870.1 ccm vs. grade 0–1: 647.3 ccm; p < 0.01) and with the irradiated volumes V5 to V50. Using VMAT planning, we could reduce mean doses and irradiated volumes for all OAR: D\(_{mean}\) bladder (21.9 Gy vs. 26.3 Gy, p < 0.01), small bowel volumes V5–V45 (p < 0.01), D\(_{mean}\) anal sphincter (34.6 Gy vs. 35.6 Gy, p < 0.01) and D\(_{mean}\) femoral heads (right 11.4 Gy vs. 25.9 Gy, left 12.5 Gy vs. 26.6 Gy, p < 0.01). Acute small bowel and bladder toxicities were dose and volume dependent. Dose and volume sparing for all OAR could be achieved through VMAT planning and might result in less acute toxicities. KW - radiotherapy KW - rectal cancer Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301255 VL - 12 ER - TY - JOUR A1 - Tamihardja, Jörg A1 - Lawrenz, Ingulf A1 - Lutyj, Paul A1 - Weick, Stefan A1 - Guckenberger, Matthias A1 - Polat, Bülent A1 - Flentje, Michael T1 - Propensity score-matched analysis comparing dose-escalated intensity-modulated radiation therapy versus external beam radiation therapy plus high-dose-rate brachytherapy for localized prostate cancer JF - Strahlentherapie und Onkologie N2 - Purpose Dose-escalated external beam radiation therapy (EBRT) and EBRT + high-dose-rate brachytherapy (HDR-BT) boost are guideline-recommended treatment options for localized prostate cancer. The purpose of this study was to compare long-term outcome and toxicity of dose-escalated EBRT versus EBRT + HDR-BT boost. Methods From 2002 to 2019, 744 consecutive patients received either EBRT or EBRT + HDR-BT boost, of whom 516 patients were propensity score matched. Median follow-up was 95.3 months. Cone beam CT image-guided EBRT consisted of 33 fractions of intensity-modulated radiation therapy with simultaneous integrated boost up to 76.23 Gy (D\(_{Mean}\)). Combined treatment was delivered as 46 Gy (D\(_{Mean}\)) EBRT, followed by two fractions HDR-BT boost with 9 Gy (D\(_{90\%}\)). Propensity score matching was applied before analysis of the primary endpoint, estimated 10-year biochemical relapse-free survival (bRFS), and the secondary endpoints metastasis-free survival (MFS) and overall survival (OS). Prognostic parameters were analyzed by Cox proportional hazard modelling. Genitourinary (GU)/gastrointestinal (GI) toxicity evaluation used the Common Toxicity Criteria for Adverse Events (v5.0). Results The estimated 10-year bRFS was 82.0% vs. 76.4% (p = 0.075) for EBRT alone versus combined treatment, respectively. The estimated 10-year MFS was 82.9% vs. 87.0% (p = 0.195) and the 10-year OS was 65.7% vs. 68.9% (p = 0.303), respectively. Cumulative 5‑year late GU ≥ grade 2 toxicities were seen in 23.6% vs. 19.2% (p = 0.086) and 5‑year late GI ≥ grade 2 toxicities in 11.1% vs. 5.0% of the patients (p = 0.002); cumulative 5‑year late grade 3 GU toxicity occurred in 4.2% vs. 3.6% (p = 0.401) and GI toxicity in 1.0% vs. 0.3% (p = 0.249), respectively. Conclusion Both treatment groups showed excellent long-term outcomes with low rates of severe toxicity. KW - long-term outcome KW - dose escalation KW - high-dose-rate brachytherapy boost KW - propensity score matching KW - toxicity Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-325055 VL - 198 IS - 8 ER - TY - JOUR A1 - Kraft, Johannes A1 - Weick, Stefan A1 - Breuer, Kathrin A1 - Lutyj, Paul A1 - Bratengeier, Klaus A1 - Exner, Florian A1 - Richter, Anne A1 - Tamihardja, Jörg A1 - Lisowski, Dominik A1 - Polat, Bülent A1 - Flentje, Michael T1 - Treatment plan comparison for irradiation of multiple brain metastases with hippocampal avoidance whole brain radiotherapy and simultaneous integrated boost using the Varian Halcyon and the Elekta Synergy platforms JF - Radiation Oncology N2 - No abstract available. KW - treatment plan KW - multiple brain metastases Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301221 VL - 17 ER -