ESTRO 2024 - Abstract Book

S1849

Clinical - Mixed sites, palliation

ESTRO 2024

Petr Burkon 1,2 , Marek Slavik 1,2 , Tomas Kazda 1,2,3 , Lukas Bobek 1 , Pavel Slampa 1,2 , Katerina Polachova 1 , Iveta Selingerova 3,4 1 Masaryk Memorial Cancer Institute, Department of Radiation Oncology, Brno, Czech Republic. 2 Faculty of Medicine, Masaryk University, Department of Radiation Oncology, Brno, Czech Republic. 3 Masaryk Memorial Cancer Institute, Research Centre for Applied Molecular Oncology (RECAMO), Brno, Czech Republic. 4 Faculty of Science, Masaryk University, Department of Radiation Oncology, Brno, Czech Republic

Purpose/Objective:

The aim of this study is to optimize the fractionation schedules for radiotherapy in the treatment of heel spurs (HSS, plantar fasciitis) through a prospective randomized open-label trial conducted at Department of Radiation Oncology at Masaryk Memorial Cancer Institute Brno (MMCI). Low-dose external beam radiotherapy (LD-EBRT), known for its anti-inflammatory effect, offers effective pain relief for HSS patients. Currently, the standard LD-EBRT regimen consists of six fractions of 1 Gray (Gy) administered twice weekly, resulting in a total dose of 6 Gy. This study posits the hypothesis that very low total doses of orthovoltage radiotherapy, delivered in a single fraction, may provide pain relief reasonable/comparable to that achieved with higher doses of fractionated radiotherapy. The primary goal of this research is to determine whether one-day irradiation (a single fraction) is non-inferior to fractionated radiotherapy over a three-month period in terms of pain relief for HSS patients. The study is motivated by the operational aspects of current real-world radiotherapy practice (staff/equipment shortages, pandemic measures etc). Supported by NU22-10-00479. All patients signed informed consent. After completing the enrollment process and filling out the SF-36 questionnaire, as well as the Calcaneodynia score (CS) and visual analogue pain score (VAS) forms, patients (pts) meeting specific inclusion criteria (over 40 years old, painful unilateral plantar HSS for at least six months, and being suitable for HSS radiotherapy), and fulfilling the main exclusion criteria (no prior history of radiotherapy for heel spur, no corticosteroid local application in the four weeks leading up to radiotherapy, no systemic rheumatic or collagen vascular diseases, lymphatic edema of the lower limb, or prior trauma and surgery on the ipsilateral foot), were randomized into six groups based on the total dose of radiotherapy. Patients in these groups received a total dose of 6 Gy in 4 fractions of 1.5 Gy twice weekly (arm A), a total dose of 3 Gy in 2 fractions of 1.5 Gy twice weekly (arm B), a single fraction of 0.5 Gy (arm C), a single fraction of 1.0 Gy (arm D), a single fraction of 1.5 Gy (arm E), and a single fraction of 2 Gy (arm F), respectively. The regimen in arm A (6 Gy in 4 fractions) is commonly used in MMCI and is considered as the control arm in this trial. In the event of inadequate pain relief, reirradiation was performed with a total dose of 6 Gy in 4 fractions of 1.5 Gy twice weekly after a waiting period of three months in any of the aforementioned groups. Total number of 966 patients will be enrolled. Material/Methods:

Results:

We present our initial data following the assessment of the impact of radiotherapy on 274 patients who were enrolled between September 2022 and August 2023. Reirradiation after three months was necessary in the following percentages of patients in each treatment arm: A arm (12/45 pts, 27%), B arm (24/48 pts, 50%), C arm (24/45 pts, 53%), D arm (24/44 pts, 55%), E arm (20/44 pts, 45%), and F arm (28/48 pts, 58%), respectively. The percentages of patients experiencing any pain relief were as follows: Arm A (47%), B (48%), C (47%), D (50%), E (50%),