Background: Follow-up after treatment for hepatocellular carcinoma (HCC) can be mostly performed using dynamic CT or MRI, but there is no common evaluation method after radiation therapy. The purpose of this study is to examine factors involved in tumor reduction and local recurrence in patients with HCC treated with proton beam therapy (PBT) and to evaluate HCC shrinkage after PBT. Methods: Cases with only one irradiated lesion or those with two lesions irradiated simultaneously were included in this study. Pre- and post-treatment lesions were evaluated using Response Evaluation Criteria in Solid Tumors (RECIST) by measuring the largest diameter. Results: The 6-, 12-, and 24-month CR + PR rates after PBT were 33.1%, 57.5%, and 76.9%, respectively, and the reduction rates were 25.1% in the first 6 months, 23.3% at 6–12 months, and 14.5% at 13–24 months. Cases that reached CR/PR at 6 and 12 months had improved OS compared to non-CR/non-PR cases. Conclusions: It is possible that a lesion that reached SD may subsequently transition to PR; it is reasonable to monitor progress with periodic imaging evaluations even after 1 year of treatment.
背景：肝细胞癌（HCC）治疗后的随访大多可通过动态CT或MRI进行，但放射治疗后尚无统一的评估方法。本研究旨在探讨接受质子束治疗（PBT）的HCC患者肿瘤缩小及局部复发的影响因素，并评估PBT后HCC的消退情况。方法：本研究纳入仅有一个照射病灶或两个病灶同时接受照射的病例。采用实体瘤疗效评价标准（RECIST），通过测量最大直径对治疗前后的病灶进行评估。结果：PBT后6、12、24个月的完全缓解（CR）+部分缓解（PR）率分别为33.1%、57.5%和76.9%；缩小率在前6个月为25.1%，6-12个月为23.3%，13-24个月为14.5%。在6个月和12个月达到CR/PR的病例总生存期（OS）优于未达到CR/PR的病例。结论：达到疾病稳定（SD）的病灶后续可能转为PR；即使在治疗1年后，通过定期影像学评估监测病情进展是合理的。
Tumor Response on Diagnostic Imaging after Proton Beam Therapy for Hepatocellular Carcinoma
肿瘤(癌症)患者之家