ESTRO 2024 - Abstract Book

S1585

Clinical - Lung

ESTRO 2024

5. Faught AM, Yamamoto T, Castillo R, Castillo E, Zhang J, Vinogradskiy Y. Evaluating Which Dose-Function Metrics Are Most Critical for Functional-Guided Radiation Therapy. Int J Radiat Oncol Biol Phys. 2017 Sep 1;99(1):202-209

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Digital Poster

Malignant Pleural mesothelioma:is there role for hypofractionated radiotherapy in adjuvant setting?

Elisabetta Parisi 1 , Donatella Arpa 1 , Luca Luzzi 2 , Lucia fabbri 3 , Martina Pieri 1 , Luca Tontini 1 , Emiliano Loi 4 , Elisa Neri 1 , Simona Cima 1 , Giulia Ghigi 1 , Flavia Foca 3 , Romeo Naim Abousiam 1 , Marco Angelo Burgio 5 , Antonino Romeo 1 1 1 IRCCS Istituto Romagnolo per lo Studio dei Tumori;Dino Amadori, IRST Meldola (FC), Italy., Radiotherapy, Meldola, Italy. 2 2 University of Study of Siena, Siena ,Italy., Thoracic Surgery and Transplantation, Siena, Italy. 3 1 IRCCS Istituto Romagnolo per lo Studio dei Tumori;Dino Amadori, IRST Meldola (FC), Italy., Unit of Biostatistics and Clinical Trials, Meldola, Italy. 4 1 IRCCS Istituto Romagnolo per lo Studio dei Tumori;Dino Amadori, IRST Meldola (FC), Italy., Medical Physics Unit, Meldola, Italy. 5 1 IRCCS Istituto Romagnolo per lo Studio dei Tumori;Dino Amadori, IRST Meldola (FC), Italy., Oncological department, Meldola, Italy Malignant pleural mesothelioma (MPM) is most often limited to the ipsilateral pleura, local control is the primary aim after pleurectomy/decortication (P/D) surgery. Radiation therapy has traditionally a role in many malignancies as adjuvant treatment in order to reduce local failure. Literature data report the role of radiotherapy in conventional fractionation after pleurectomy/decortication in the treatment of MPM. To date, no large studies were found in literature regarding alternatives to the conventional dose schemes in the MPM adjuvant setting such as accelerated hypofractionated radiotherapy. We report the first results of an ongoing prospective trial about hypofractionated radiotherapy after P/D in MPM patients. The primary endpoint of this study was to evaluate acute and late pulmonary toxicity of the novel adjuvant RT treatment strategy in MPM patients who underwent chemotherapy and pleurectomy/decortication (P/D). The secondary endpoints were overall survival (OS) for all enrolled patients and time to progression (TTP) for patients with documented progression disease. We report the toxicity preliminary results of the first 20 patients enrolled. Purpose/Objective:

Material/Methods:

Between July 2017 to June 2023, 29 MPM patients were enrolled and treated with accelerated hypofractionated radiotherapy using helical Tomotherapy and intensity-modulated arc therapy. We conducted a prospective mono institutional clinical trial enrolling cyto-histological proven, MPM patients. The dose prescription to the target was 30 Gy in five daily fractions (at the reference isodose 60 – 70%) with an internal increasing inhomogeneous dose of up to 40 Gy for GTV (gross tumor volume); the dose prescription for CTV (clinical target volume) was 30 Gy in five daily fractions without the internal increasing inhomogeneous dose if there was not a tumor positive margin. Steroids (methylprednisolone 4 mg daily) were prescribed from the first day of treatment for 30 consecutive days to control radiation-induced homolateral pulmonary inflammation.