Background/Objectives:Carbon-ion radiotherapy (CIRT) is a promising treatment option for unresectable locally recurrent rectal cancer (LRRC). However, CIRT is contraindicated in cases where recurrent tumors are attached to the intestine. To address this limitation, we developed a novel treatment strategy involving curative-dose CIRT to recurrent tumors, including the adjacent intestine, without dose constraints, followed by surgical resection of the irradiated intestine. This study aimed to assess the feasibility of this approach.Methods:Patients were eligible for this study if the distance between the unresectable recurrent tumor and the adjacent intestines was less than 3 mm. Between 2019 and 2023, twelve patients were enrolled. CIRT was administered at curative doses of 70.4 or 73.6 Gy (relative biologic effectiveness (RBE)), including the adjacent intestines, without dose constraints. Surgical resection was not intended to excise the tumor itself, but was performed solely to remove the irradiated intestines. Irradiated intestine resection was planned within eight weeks after the completion of CIRT.Results:All patients completed the scheduled treatment course. The median interval between completing CIRT and surgery was 4 (3–8) weeks. No patients experienced acute AEs related to CIRT. Regarding late AEs, two patients developed Grade I sciatic neuralgia, and one patient developed Grade III neuralgia. We considered this symptom, which later resulted in a limp in his left leg, acceptable because this patient could ambulate with assistance. Clavien–Dindo Grade III postoperative complications occurred in one patient. The median follow-up duration was 40 (20–60) months. One patient was diagnosed with in-field recurrence, and three patients were diagnosed with out-of-field recurrence. These patients received reirradiation with CIRT. Four patients experienced lung recurrence, and one patient died from rectal-cancer-specific causes.Conclusions:This novel treatment strategy may provide favorable outcomes for patients with unresectable LRRC. This approach can be applied to the currently accepted indications for CIRT, and we believe that CIRT is a feasible treatment option for future patients.
背景/目的：碳离子放射治疗（CIRT）是不可切除局部复发性直肠癌（LRRC）的一种前景广阔的治疗选择。然而，当复发性肿瘤与肠道粘连时，CIRT是禁忌的。为解决这一限制，我们开发了一种新的治疗策略：对复发性肿瘤（包括邻近肠道）进行根治剂量的CIRT，不设剂量限制，随后手术切除受照射的肠道。本研究旨在评估该方法的可行性。 方法：若不可切除的复发性肿瘤与邻近肠道的距离小于3毫米，患者则符合本研究入组条件。2019年至2023年间，共纳入12名患者。CIRT以70.4或73.6 Gy（相对生物效应）的根治剂量实施，照射范围包括邻近肠道，且无剂量限制。手术切除的目的并非切除肿瘤本身，而仅是为了移除受照射的肠道。计划在CIRT完成后八周内进行受照射肠道的切除术。 结果：所有患者均完成了预定的治疗过程。完成CIRT至手术的中位间隔时间为4（3-8）周。无患者出现与CIRT相关的急性不良事件。关于晚期不良事件，两名患者出现I级坐骨神经痛，一名患者出现III级神经痛。我们认为该症状（后来导致其左腿跛行）是可接受的，因为该患者可在辅助下行走。一名患者发生了Clavien-Dindo III级术后并发症。中位随访时间为40（20-60）个月。一名患者被诊断为照射野内复发，三名患者被诊断为照射野外复发。这些患者接受了CIRT再程放疗。四名患者出现肺部复发，一名患者因直肠癌特异性原因死亡。 结论：这种新的治疗策略可能为不可切除的LRRC患者带来良好的预后。该方法可应用于目前公认的CIRT适应症，我们相信CIRT对于未来的患者是一种可行的治疗选择。
肿瘤(癌症)患者之家