Department of Radiation Oncology, Centre Jean Bernard, Le Mans, France.
Int J Radiat Oncol Biol Phys. 2010 Nov 15;78(4):975-82. doi: 10.1016/j.ijrobp.2010.06.056.
The extreme radiosensitivity of indolent lymphomas was reported in the early years of radiotherapy (RT). The efficacy of low-dose total body irradiation (1.5-2 Gy) was particularly demonstrative. Higher doses were considered appropriate for localized disease. The optimal (or conventional) dose of curative RT derived from the early studies was determined to be 30-35 Gy. Nevertheless, in older series addressing the tumoricidal radiation dose in non-Hodgkin's lymphomas, investigators noted that a significant number of "nodular" lymphomas were controlled with a dose of <22 Gy for >3 years. The idea of reintroducing localized low-dose radiotherapy (LDRT) for indolent non-Hodgkin's lymphomas came from a clinical observation. The first study showing the high efficacy of LDRT (4 Gy in two fractions of 2 Gy within 3 days) in selected patients with chemoresistant, indolent, non-Hodgkin's lymphomas was published in 1994. Since this first report, at least eight series of patients treated with localized LDRT have been published, showing a 55% complete response rate in irradiated sites, with a median duration of 15-42 months. How LDRT induces lymphoma cell death remains partly unknown. However, some important advances have recently been reported. Localized LDRT induces an apoptosis of follicular lymphoma cells. This apoptotic cell death elicits an immune response mediated by macrophages and dendritic cells. Follicular lymphoma is probably an ideal model to explore these mechanisms. This review also discusses the future of LDRT for follicular lymphoma.
惰性淋巴瘤的极端放射敏感性在放射治疗（RT）的早期就有报道。低剂量全身照射（1.5-2 Gy）的疗效尤其显著。对于局限性疾病，更高的剂量被认为是合适的。从早期研究中得出的治愈性 RT 的最佳（或常规）剂量被确定为 30-35 Gy。然而，在较早的研究中，关于非霍奇金淋巴瘤的肿瘤杀伤剂量的系列研究中，研究人员注意到，相当数量的“结节性”淋巴瘤在 22 Gy 以下的剂量下，>3 年得到了控制。引入局部低剂量放疗（LDRT）治疗惰性非霍奇金淋巴瘤的想法源于临床观察。第一项表明 LDRT（在 3 天内分 2 次给予 2 Gy，每次 4 Gy）在化学耐药性、惰性、非霍奇金淋巴瘤患者中具有高效的研究于 1994 年发表。自首次报告以来，至少有八项关于接受局部 LDRT 治疗的患者的系列研究已经发表，显示出在照射部位的完全缓解率为 55%，中位持续时间为 15-42 个月。LDRT 如何诱导淋巴瘤细胞死亡仍部分未知。然而，最近有一些重要的进展被报道。局部 LDRT 诱导滤泡性淋巴瘤细胞凋亡。这种凋亡细胞死亡引发由巨噬细胞和树突状细胞介导的免疫反应。滤泡性淋巴瘤可能是探索这些机制的理想模型。这篇综述还讨论了 LDRT 治疗滤泡性淋巴瘤的未来。
