Image-guided brachytherapy for pediatric bladder and/or prostate rhabdomyosarcoma: toward an increased personalization of treatment.: Brachytherapy in uro-pediatric rhabdomyosarcoma

Eymeric Le Reun; Sophie Espenel; Max-Adrien Garcia; Anamaria Hermina Girbovan; Mario Terlizzi; Véronique Minard-Colin; Théo Lasseau; Florent Guérin; Cyrus Chargari

doi:10.1016/j.ijrobp.2024.09.037

Image-guided brachytherapy for pediatric bladder and/or prostate rhabdomyosarcoma: toward an increased personalization of treatment.: Brachytherapy in uro-pediatric rhabdomyosarcoma

Int J Radiat Oncol Biol Phys. 2024 Sep 20:S0360-3016(24)03405-9. doi: 10.1016/j.ijrobp.2024.09.037. Online ahead of print.

Authors

Eymeric Le Reun¹, Sophie Espenel², Max-Adrien Garcia³, Anamaria Hermina Girbovan², Mario Terlizzi², Véronique Minard-Colin⁴, Théo Lasseau⁴, Florent Guérin⁵, Cyrus Chargari⁶

Affiliations

¹ Department of Radiation Oncology, Gustave Roussy Cancer Campus, Cancer Center, Villejuif, France; Inserm, U1296 Unit, "Radiation: Defense, Health and Environment", Centre Léon-Bérard, 28 rue Laennec, 69008 Lyon, France.
² Department of Radiation Oncology, Gustave Roussy Cancer Campus, Cancer Center, Villejuif, France.
³ Department of Medical Information, Institute Mutualiste Montsouris, Paris, France.
⁴ Department of Pediatric Oncology, Gustave Roussy Cancer Campus, Cancer Center, University Paris Saclay Medical Faculty, Villejuif, France.
⁵ Department of Pediatric Surgery, Bicêtre Hospital, Paris-Saclay University, Assistance Publique Hôpitaux de Paris, Le Kremlin Bicêtre, France.
⁶ Department of Radiation Oncology, Gustave Roussy Cancer Campus, Cancer Center, Villejuif, France; INSERM 1030 Molecular radiotherapy, Gustave Roussy Cancer Campus, Villejuif, France. Electronic address: cyrus.chargari@aphp.fr.

PMID: 39307320
DOI: 10.1016/j.ijrobp.2024.09.037

Abstract

Introduction: Rhabdomyosarcoma (RMS) is the most common soft tissue cancer in children. Around 15% of RMS involve the bladder and/or prostate (BP). Overall survival is around 85%. After chemotherapy, patients receive local treatment based on surgery and/or radiotherapy. In recent decades, image guidance and pulsed dose-rate (PDR) brachytherapy have made it possible to personalize treatment, reduce radiation-related toxicity, while maintaining a good tumor control. We report one of the largest series of image-guided brachytherapy for pediatric RMS BP.

Material and methods: The clinical and dosimetric parameters of children treated with brachytherapy for BP RMS between July 2014 and September 2020 were retrospectively reviewed. Patients were treated with a multimodal conservative approach, combining partial conservative surgery (preservation of the bladder neck and urethra), followed by an interstitial brachytherapy procedure. Iridium-192 PDR treatment was administered on the basis of CT and MRI planning. Toxicities were reported according to version 4.0 of the Common Terminology Criteria for Adverse Events.

Results: A total of 75 patients were identified, with a median age of 29 months (range 2-84) at diagnosis. The median brachytherapy dose was 60.06 Gy (143 pulses, 0.42 Gy/pulse). With a median follow-up of 44.1 months (range 0.7-90), the 5-year OS and PFS rates were 97.3% and 92% respectively. Median D50% for the bladder and D1cc for the rectum were 38.6 Gy and 49 Gy respectively. The 5-year probability of survival without severe late urinary toxicity (grade 3 or higher) was estimated at 78.8% (CI_95%: 68.1-91.1). A total of 9.3% of children experienced grade 2 or 3 late rectal toxicity.

Conclusions: Image-guided PDR brachytherapy offers a personalized treatment for pediatric BP RMS, with a favorable therapeutic index. No prognostic factors for urinary toxicity have been identified. Multicenter studies with larger numbers of patients are needed to clarify these data.

Keywords: Rhabdomyosarcoma; brachytherapy; conservative treatment; pediatric; toxicity; urinary.