Michalet Morgan, Bordeau Karl, Cantaloube Marie, Valdenaire Simon, Debuire Pierre, Simeon Sebastien, Portales Fabienne, Draghici Roxana, Ychou Marc, Assenat Eric, Dupuy Marie, Gourgou Sophie, Colombo Pierre-Emmanuel, Carrere Sebastien, Souche François-Regis, Aillères Norbert, Fenoglietto Pascal, Azria David, Riou Olivier
University Federation of Radiation Oncology of Mediterranean Occitanie, Montpellier Cancer Institute (ICM), Univ Montpellier, INSERM U1194 Institut de Recherche en Cancérologie de Montpellier (IRCM), Montpellier, France.
Medical Oncology Department, Institut du Cancer de Montpellier (ICM), Montpellier Cancer Institute, Univ Montpellier, Montpellier, France.
Front Oncol. 2022 Mar 9;12:842402. doi: 10.3389/fonc.2022.842402. eCollection 2022.
Stereotactic MR-guided adaptive radiotherapy (SMART) is an attractive modality of radiotherapy for pancreatic tumors. The objectives of this prospective registry study were to report the dosimetric benefits of daily adaptation of SMART and the first clinical results in pancreatic tumors.
All patients treated in our center with SMART for a pancreatic tumor were included. Patients were planned for five daily-adapted fractions on consecutive days. Endpoints were acute toxicities, late toxicities, impact of adaptive treatment on target volume coverage and organs at risk (OAR) sparing, local control (LC) rate, distant metastasis-free survival (DMFS), and overall survival (OS).
Thirty consecutive patients were included between October 2019 and April 2021. The median dose prescription was 50 Gy. No patient presented grade > 2 acute toxicities. The most frequent grade 1-2 toxicities were asthenia (40%), abdominal pain (40%), and nausea (43%). Daily adaptation significantly improved planning target volume (PTV) and gross tumor volume (GTV) coverage and OAR sparing. With a median follow-up of 9.7 months, the median OS, 6-month OS, and 1-year OS were 14.1 months, 89% (95% CI: 70%-96%), and 75% (95% CI: 51%-88%), respectively, from SMART completion. LC at 6 months and 1 year was respectively 97% (95% CI: 79-99.5%) and 86% (95% CI: 61%-95%). There were no grade > 2 late toxicities. With a median follow-up of 10.64 months, locally advanced pancreatic cancer (LAPC) and borderline resectable pancreatic cancer (BRPC) patients (22 patients) had a median OS, 6-month OS, and 1-year OS from SMART completion of 14.1 months, 76% (95% CI: 51%-89%), and 70% (95% CI: 45%-85%), respectively. Nine patients underwent surgical resection (42.1% of patients with initial LAPC and 33.3% of patients with BRPC), with negative margins (R0). Resected patients had a significantly better OS as compared to unresected patients (p = 0.0219, hazard ratio (HR) = 5.78 (95% CI: 1.29-25.9)).
SMART for pancreatic tumors is feasible without limiting toxicities. Daily adaptation demonstrated a benefit for tumor coverage and OAR sparing. The severity of observed acute and late toxicities was low. OS and LC rates were promising. SMART achieved a high secondary resection rate in LAPC patients. Surgery after SMART seemed to be feasible and might increase OS in these patients.
立体定向磁共振引导自适应放疗（SMART）是一种针对胰腺肿瘤颇具吸引力的放疗方式。这项前瞻性注册研究的目的是报告SMART每日适应性放疗的剂量学益处以及胰腺肿瘤的首批临床结果。
纳入在我们中心接受SMART治疗胰腺肿瘤的所有患者。患者计划连续5天每天进行适应性分次放疗。观察终点包括急性毒性反应、晚期毒性反应、适应性治疗对靶区体积覆盖和危及器官（OAR）保护的影响、局部控制（LC）率、无远处转移生存期（DMFS）和总生存期（OS）。
2019年10月至2021年4月期间连续纳入30例患者。中位剂量处方为50 Gy。无患者出现>2级急性毒性反应。最常见的1-2级毒性反应为乏力（40%）、腹痛（40%）和恶心（43%）。每日适应性放疗显著改善了计划靶区体积（PTV）和大体肿瘤体积（GTV）的覆盖情况以及对OAR的保护。中位随访9.7个月，自SMART治疗结束起，中位OS、6个月OS和1年OS分别为14.1个月、89%（95%CI：70%-96%）和75%（95%CI：51%-88%）。6个月和1年时的LC率分别为97%（95%CI：79-99.5%）和86%（95%CI：61%-95%）。无>2级晚期毒性反应。中位随访10.64个月，局部晚期胰腺癌（LAPC）和临界可切除胰腺癌（BRPC）患者（共22例）自SMART治疗结束起的中位OS、6个月OS和1年OS分别为14.1个月、76%（95%CI：51%-89%）和70%（95%CI：45%-85%）。9例患者接受了手术切除（初始LAPC患者中的42.1%和BRPC患者中的33.3%），切缘阴性（R0）。与未接受手术切除的患者相比，接受手术切除的患者OS明显更好（p = 0.0219，风险比（HR）= 5.78（95%CI：1.29-25.9））。
SMART用于胰腺肿瘤治疗是可行的，且不增加毒性反应。每日适应性放疗对肿瘤覆盖和OAR保护有益。观察到的急性和晚期毒性反应严重程度较低。OS和LC率前景良好。SMART在LAPC患者中实现了较高的二次切除率。SMART后进行手术似乎可行，且可能提高这些患者的OS。
