Impact of Dose-Escalated Chemoradiation on Pathological Complete Response in Patients with Locally Advanced Rectal Cancer

Simple Summary Approximately 40% of all diagnoses of rectal cancer in Spain are locally advanced. A multimodal treatment is needed, and one of its pillars is radiotherapy, with a classic dose scheme of up to 50-50.4 Gy concomitantly with oral capecitabine or 5-fluorouracil. Dose escalation is being...

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Detalles Bibliográficos
Autores: Domingo-Boluda, C, Dualde, D, Taberner-Bonastre, T, Soler, M, López-Campos, F
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana (FISABIO)
Repositorio:r-FISABIO. Repositorio Institucional de Producción Científica
OAI Identifier:oai:fisabio.fundanetsuite.com:p17863
Acceso en línea:https://fisabio.portalinvestigacion.com/publicaciones/17863
Access Level:acceso abierto
Palabra clave:locally advanced rectal cancer
neoadjuvant
chemoradiotherapy
radiotherapy dose escalation
pathological complete response
Descripción
Sumario:Simple Summary Approximately 40% of all diagnoses of rectal cancer in Spain are locally advanced. A multimodal treatment is needed, and one of its pillars is radiotherapy, with a classic dose scheme of up to 50-50.4 Gy concomitantly with oral capecitabine or 5-fluorouracil. Dose escalation is being explored to achieve higher rates of a pathological complete response, but the optimal dose and its impact on the outcomes are unclear. Our study aimed to evaluate the percentage of complete pathological responses obtained with an intensified neoadjuvant radiotherapy treatment scheme. We confirmed in a homogeneous population (49 patients treated with standard radiotherapy vs. 50 patients treated with dose-escalated radiotherapy) higher rates of a pathological complete response with a dose of up to 54 Gy concomitantly with oral capecitabine. Neoadjuvant radiotherapy intensification is useful for specimen sterilization and should be offered to selected patients.Abstract Locally advanced rectal cancer requires a multimodal treatment. Radiotherapy is being explored for intensification to improve the rates of pathological complete responses (ypCR rates) which are correlated with better outcomes. This study reports a comparison between standard versus escalated doses in a preoperative scenario. The ypCR rates, toxicity, postoperative complications, and disease-free and overall survival at 5 years are described. From 2012 to 2019, 99 patients were analyzed retrospectively: standard arm (mean of 47.5 Gy) vs. dose-escalated arm (mean of 54.3 Gy). All patients were treated with 3DRT in 25 fractions, with concomitant capecitabine and surgery performed according to the total mesorectal excision principles in both arms. The ypCR was reported using the "College of American Pathologist grades"; the gastrointestinal (GI) and genitourinary (GU) toxicity was reported using the "Common Terminology Criteria for Adverse Events" (CTCAE 4.0). The ypCR rates were higher in the dose-escalated group (25% vs. 10.64%; p = 0.07), with a lower rate of non-treatment response (61.36% vs. 38.64%; p = 0.11). No statistical differences between the arms were found in terms of the oncological outcomes, postoperative complications (p = 0.15), second surgeries (p = 0.62), or deaths (p = 0.62). The CTCAE acute GI and GU toxicity were grade I or II in both arms. Our study presents a long-term follow-up in comparative cohorts.