Dimopoulos Platon M, Sotirchos Vlasios S, Dunne-Jaffe Cynthia, Petre Elena N, Gonen Mithat, Zhao Ken, Kirov Assen S, Crane Christopher, D'Angelica Michael, Connell Louise C, Sofocleous Constantinos T
From the Interventional Oncology/Radiology Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY.
Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY.
Clin Nucl Med. 2025 Feb 1;50(2):133-142. doi: 10.1097/RLU.0000000000005565.
Radiation segmentectomy (RS) is an alternative potential local curative treatment for selected colorectal liver metastases (CLMs) not amenable to ablation or limited resection.
The aim of this study was to evaluate the dosimetric response of low volume CLMs to RS in heavily pretreated patients who are not candidates for resection or percutaneous ablation.
This single-center retrospective study evaluated CLMs patients treated with RS (prescribed tumor dose >190 Gy) from 2015 to 2023. RS doses to tumor(s) and margins were calculated from SPECT/CT and PET/CT images. Response and local tumor progression (LTP) were assessed using anatomic (RECIST 1.1) and metabolic (PERCIST) criteria. LTP-free survival (LTPFS) and overall survival were estimated with Kaplan-Meier methodology. Variables were assessed as predictors of LTPFS using the Cox proportional hazards model.
Thirty-six patients underwent 38 RS procedures to treat 57 tumors. Median time from initial diagnosis to detection of liver metastases and RS were 16.4 (interquartile range: 6.5-32.2) and 26.8 (interquartile range: 12.5-40.0) months, respectively. Median overall survival after RS was 14.3 (95% confidence interval [CI]: 10.8-30.7) months. Predictors of LTPFS included tumor number(s), mean tumor dose (MTD), and margin mean absorbed dose (MMAD). Complete radiographic (hazards ratio [HR]: 1.29e-16, 95% CI: 4.06e-17-4.07e-16, P < 0.001) and metabolic response (HR: 0.38, 95% CI: 0.15-0.95, P = 0.038) correlated with prolonged LTPFS. One-year LTPFS rate was 83.3% for tumors receiving MTD ≥400 Gy and a 5-mm surrounding MMAD ≥350 Gy ( P = 0.006). No instances of LTP were observed when tumors received stereotactic irradiation over 300 Gy (at least 95% of the tumor volume received ≥300 Gy). One-year LTPFS rate for tumors receiving MTD ≥400 Gy was 68.6% versus 14.3% for those that did not reach this threshold ( P = 0.013). In multivariate analysis, MTD ≥400 Gy and 5-mm MMAD ≥350 Gy were independent predictors of LTPFS (HR: 0.11; 95% CI: 0.01-0.81; P = 0.03).
MTD ≥400 Gy, MMAD ≥350 Gy, and stereotactic tumor irradiation ≥300 Gy are associated with prolonged LTPFS after RS for CLMs.
放射段切除术（RS）是一种针对某些无法进行消融或有限切除的结直肠癌肝转移（CLM）患者的潜在局部根治性替代治疗方法。
本研究旨在评估在接受过大量治疗且不适合进行切除或经皮消融的患者中，小体积CLM对RS的剂量学反应。
这项单中心回顾性研究评估了2015年至2023年接受RS治疗（规定肿瘤剂量>190 Gy）的CLM患者。根据SPECT/CT和PET/CT图像计算肿瘤及切缘的RS剂量。使用解剖学标准（RECIST 1.1）和代谢标准（PERCIST）评估反应和局部肿瘤进展（LTP）。采用Kaplan-Meier方法估计无LTP生存期（LTPFS）和总生存期。使用Cox比例风险模型评估变量作为LTPFS的预测因素。
36例患者接受了38次RS手术以治疗57个肿瘤。从初次诊断到发现肝转移和RS的中位时间分别为16.4个月（四分位间距：6.5 - 32.2）和26.8个月（四分位间距：12.5 - 40.0）。RS后的中位总生存期为14.3个月（95%置信区间[CI]：10.8 - 30.7）。LTPFS的预测因素包括肿瘤数量、平均肿瘤剂量（MTD）和切缘平均吸收剂量（MMAD）。完全影像学缓解（风险比[HR]：1.29e - 16，95% CI：4.06e - 17 - 4.07e - 16，P < 0.001）和代谢缓解（HR：0.38，95% CI：0.15 - 0.95，P = 0.038）与延长的LTPFS相关。对于接受MTD≥400 Gy且5毫米周围MMAD≥350 Gy的肿瘤，一年LTPFS率为83.3%（P = 0.006）。当肿瘤接受超过300 Gy的立体定向照射（至少95%的肿瘤体积接受≥300 Gy）时，未观察到LTP病例。接受MTD≥400 Gy的肿瘤一年LTPFS率为68.6%，而未达到该阈值的肿瘤为14.3%（P = 0.（此处原文可能有误，推测应为P = 0.013）。在多变量分析中，MTD≥400 Gy和5毫米MMAD≥350 Gy是LTPFS的独立预测因素（HR：0.11；95% CI：0.01 - 0.81；P = 0.03）。
MTD≥400 Gy、MMAD≥350 Gy和立体定向肿瘤照射≥300 Gy与CLM患者RS后延长的LTPFS相关。
