Department of Radiation Oncology, City of Hope National Medical Center, Duarte, California.
Department of Hematology/Hematopoietic Cell Transplantation, City of Hope National Medical Center, Duarte, California.
Int J Radiat Oncol Biol Phys. 2014 May 1;89(1):75-81. doi: 10.1016/j.ijrobp.2014.01.036.
Approximately 5% to 20% of patients who undergo total body irradiation (TBI) in preparation for hematopoietic cell transplantation (HCT) can develop extramedullary (EM) relapse. Whereas total marrow and lymphoid irradiation (TMLI) provides a more conformally targeted radiation therapy for patients, organ sparing has the potential to place the patient at a higher risk for EM relapse than TBI. This study evaluated EM relapse in patients treated with TMLI at our institution.
Patients eligible for analysis had been enrolled in 1 of 3 prospective TMLI trials between 2006 and 2012. The TMLI targeted bones, major lymph node chains, liver, spleen, testes, and brain, using image-guided tomotherapy with total dose ranging from 12 to 15 Gy.
A total of 101 patients with a median age of 47 years were studied. The median follow-up was 12.8 months. Incidence of EM relapse and bone marrow (BM) relapse were 12.9% and 25.7%, respectively. Of the 13 patients who had EM relapse, 4 also had BM relapse, and 7 had EM disease prior to HCT. There were a total of 19 EM relapse sites as the site of initial recurrence: 11 soft tissue, 6 lymph node, 2 skin. Nine of these sites were within the target region and received ≥12 Gy. Ten initial EM relapse sites were outside of the target region: 5 sites received 10.1 to 11.4 Gy while 5 sites received <10 Gy. Pretransplantation EM was the only significant predictor of subsequent EM relapse. The cumulative incidence of EM relapse was 4% at 1 year and 11.4% at 2 years.
EM relapse incidence was as frequent in regions receiving ≥10 Gy as those receiving <10 Gy. EM relapse rates following TMLI that included HCT regimens were comparable to published results with regimens including TBI and suggest that TMLI is not associated with an increased EM relapse risk.
在接受造血细胞移植（HCT）前进行全身照射（TBI）的患者中，约有 5%至 20%可能发生骨髓外（EM）复发。虽然全骨髓和淋巴照射（TMLI）为患者提供了更适形靶向的放射治疗，但器官保存有可能使患者发生 EM 复发的风险高于 TBI。本研究评估了我们机构接受 TMLI 治疗的患者的 EM 复发情况。
有资格进行分析的患者于 2006 年至 2012 年期间参加了 3 项前瞻性 TMLI 试验中的 1 项。TMLI 采用图像引导的托姆治疗，靶向骨骼、主要淋巴结链、肝脏、脾脏、睾丸和大脑，总剂量范围为 12 至 15 Gy。
共纳入 101 例中位年龄为 47 岁的患者。中位随访时间为 12.8 个月。EM 复发和骨髓（BM）复发的发生率分别为 12.9%和 25.7%。在 13 例发生 EM 复发的患者中，4 例同时发生 BM 复发，7 例在 HCT 前存在 EM 疾病。共有 19 个 EM 复发部位作为首发复发部位：11 个软组织、6 个淋巴结、2 个皮肤。其中 9 个部位位于靶区，接受的剂量≥12 Gy。10 个初始 EM 复发部位位于靶区之外：5 个部位接受的剂量为 10.1 至 11.4 Gy，5 个部位接受的剂量<10 Gy。移植前 EM 是随后发生 EM 复发的唯一显著预测因素。EM 复发的累积发生率为 1 年后 4%，2 年后 11.4%。
在接受剂量≥10 Gy 和<10 Gy 的区域，EM 复发的发生率相同。接受包含 HCT 方案的 TMLI 后发生 EM 复发的比例与包含 TBI 的方案的发表结果相当，这表明 TMLI 与 EM 复发风险增加无关。
