ESTRO 2023 - Abstract Book

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ESTRO 2023

Locoregional HRT +/- SIB is feasible with low acute and late toxicity without significant differences in toxicities between the different RT techniques. Pts with SIB prescription who registered slightly higher toxicity, were treated with Tomotherapy. CHT appears to worsen acute toxicity.

PO-1249 Stereotactic APBI for early-stage breast cancer: 3-year outcomes of a prospective registry

J. Cantalino 1 , M. Pernia Marin 2 , D. D'Ambrosio 3 , A. Hirsch 4 , M. Danner 1 , S. Rudra 1 , S. Suy 1 , S. Collins 1 , D. Matsanka 5 , M. Good 5 , J. Feng 5 , J. Lamond 5 , D. Markiewicz 5 , R. Lanciano 5 , O. Obayomi-Davies 6 , B. Collins 7 1 Medstar Georgetown University Hospital, Department of Radiation Medicine, Washington, DC, USA; 2 The George Washington University Hospital, Geriatric and Palliative Care Division, Washington, DC, USA; 3 Community Medical Center, New Jersey Cyberknife, Toms River, NJ, USA; 4 Advocate Lutheran General Hospital, Illinois Cyberknife, Park Ridge, IL, USA; 5 Crozer Keystone Health Care Center, Philadelphia Cyberknife, Philadelphia, PA, USA; 6 Wellstar Medical Group, Department of Radiation Oncology, Marietta, GA, USA; 7 Tampa General Hospital, Department of Radiation Oncology, Tampa, FL, USA Purpose or Objective Outcomes following adjuvant accelerated partial breast irradiation (APBI) in select women with early-stage breast cancer are comparable to whole breast irradiation. Robotic stereotactic accelerated partial breast irradiation (RSAPBI) with fiducial tracking is an attractive adjuvant treatment option, but limited outcomes data are available for this approach. We report 3-year outcomes for a prospective multi-institutional registry treating select women with RSAPBI. Materials and Methods Post-menopausal women with DCIS and Stage IA breast cancer were treated over a five-year period extending from November 2015 to November 2020 and were followed for a minimum of 24 months. Treatments were delivered with a robotic radiosurgery system. Four gold fiducials were implanted around the lumpectomy cavity prior to the start of treatment for tumor bed delineation and target tracking. The CTV was defined as the lumpectomy cavity with a uniform 5 15 mm expansion confined to the breast tissue and the PTV was defined as the CTV with a 0-5 mm uniform expansion. The PTV was prescribed 30 Gy in 5 fractions. Disease status, toxicity, and cosmetic assessments were completed at 4 weeks, 3 months, 6 months, 12 months, 18 months, 24 months and yearly intervals thereafter for five years. Cosmesis was scored per the Harvard Breast Cosmesis Scale and toxicity was graded per RTOG toxicity criteria. Results Eighty-one patients (median age 68 years) with hormone receptor-positive tumors were treated over a median 9 days (range, 5-15). Sixty-eight women had invasive ductal carcinoma (84%) and thirteen had DCIS (16%). The median treated PTV was 108 cm3 (IQR 66-156) and the median prescription isodose line was 81% (IQR 79-83). The median CTV expansion was 10 mm (range 5-10) and the median PTV expansion was 3 mm (range 0-5). At a median follow up of 3 years there was one new ipsilateral breast tumor occurrence with no local, regional, or distant treatment failures. Overall survival was 95%, with no deaths due to breast cancer. Grade 1 skin toxicity was seen in two women at 3 years. No grade 2 through 4 toxicity of any kind was observed. Cosmesis at last follow-up was rated excellent for 84% and good for 15% of patients. Conclusion The 3-year outcomes of this prospective multi-institutional registry suggest that RSAPBI with fiducial tracking is a practical, effective and well-tolerated technique for the adjuvant treatment of early-stage breast cancer. Our current prospective multi-institutional registry is now enrolling elderly patients (>70 y/o) with early-stage breast cancer who decline surgery and wish to complete RSAPBI treatment alone. 1 University of Naples Federico II, Advanced Biomedical Sciences, Naples, Italy; 2 National Research Council of Italy (CNR), Institute of Biostructures and Bioimaging, Naples, Italy Purpose or Objective Radiotherapy (RT)-induced fatigue (RIF) is a clinical subtype of cancer treatment-related effect potentially impacting on patients’ Quality of Life (QoL). Wearable technologies, already available on the market, allow to monitor patients while accomplishing daily activities and to collect qualitative measurements of fatigue related biomedical parameters. Aim of our study was to infer biomedical parameters over RT treatment time able to evaluate RIF. Materials and Methods A cohort of 35 patients undergoing RT for breast cancer in the Department of Radiation Oncology (DRO) at a single institution was supplied with wearable Fitness Trackers (FT). Using FT, data (heart rate (HR), steps walked (STP) and sleep level (SLP)) was non-invasively collected. The gathered information is stored in the FT’s internal memory. Patients coming daily to the DRO for RT have data downloaded from FT’s memory via gateway devices (GW) placed in the waiting room being part of an architecture built ad hoc following the paradigm of pervasive computing. Collected data is sent to a central server and made available to medical staff through a web page. An in house script running on the server analyzes data to recognize repeated activity windows based on STP and HR. Results Applying the described methodology, it was possible to recognize different repeated activity windows for each patient over the RT treatment days. Each patient generally shows from three to five repeated activity windows in a day with at least PO-1250 Biomedical parameters identification for radiotherapy-induced fatigue evaluation:proof of principle C. Feoli 1 , A. Tramontano 2 , L. Cella 2 , R. Pacelli 1 , M. Caroprese 1 , A. Barillaro 1 , M. Petrazzuoli 1 , M. Magliulo 1