Abstract：
Hepatocellular carcinoma (HCC) is the second most common cause of cancer mortality worldwide. The risk factors associated with the development of HCC are chronic Hepatitis B, Hepatitis C, and alcoholic cirrhosis. The standard care for HCC is surgical resection but the scope is limited for some patients. Continuous advancement of radiation therapy enabled the technique of stereotactic body radiotherapy (SBRT) as an option for the treatment of those cases for which surgery cannot be done. According to recent literature and meta-analysis, SBRT is an optimum treatment method with high local control with low toxicity. In SBRT, radiation is delivered with a smaller number of fractions than conventional radiation and employs high-precision delivery and accuracy with the help of image guidance. From a series of retrospective and prospective studies, it has been confirmed that SBRT achieves excellent local control in patients with early-stage inoperable, intermediate-stage, and advanced diseases.
A 42-year-old male patient related to HBeAg infection and high AFP levels developed HCC BCLC Stage A was admitted to our department. There were two lesions with PTV volumes of 41.07 cc and 9.573 cc with a distance between them of 3.51 cm. These two lesions were treated with a mono-isocentric VMAT planning with SBRT technique. In this case, we present an unusual clinical practice of mono-isocentric treatment planning for treating multiple liver lesions. Since radiation therapy was viewed as the primary form of treatment because the patient wasn\'t an ideal candidate for surgery, SBRT was selected as the patient\'s primary modality of treatment because of the tiny volume of the two lesions and the normal liver volume (>700cc). Triple-phase 4DCT was performed for simulation to account for the motion of target volume and normal structures. After delineating the target volume and other normal structures, treatment planning was done with a dose of 45 Gray which was to be delivered in 5 fractions. Two PTVs were created with a margin of 3.0 mm to IGTV. Considering the positions of the lesions, a single isocentre plan was created using a 6MV FFF photon beam for both the PTVs with the VMAT technique. The treatment was carried through with 3 arcs, one coplanar, and the other 2 non-coplanar. At the time of treatment, after the proper positioning of the patient, one CBCT image was taken to match with the planned CT image acquired at the time of the simulation. After applying the translational and rotational errors, the patient was treated.
The patient was treated successfully. After treatment, the condition of the patient was normal, and no toxicities have been observed in follow-up.
Mono isocentric VMAT planning can be used for closely spaced lesions considering the position of lesions and other normal structures in the vicinity.
A 42-year-old male patient related to HBeAg infection and high AFP levels developed HCC BCLC Stage A was admitted to our department. There were two lesions with PTV volumes of 41.07 cc and 9.573 cc with a distance between them of 3.51 cm. These two lesions were treated with a mono-isocentric VMAT planning with SBRT technique. In this case, we present an unusual clinical practice of mono-isocentric treatment planning for treating multiple liver lesions. Since radiation therapy was viewed as the primary form of treatment because the patient wasn\'t an ideal candidate for surgery, SBRT was selected as the patient\'s primary modality of treatment because of the tiny volume of the two lesions and the normal liver volume (>700cc). Triple-phase 4DCT was performed for simulation to account for the motion of target volume and normal structures. After delineating the target volume and other normal structures, treatment planning was done with a dose of 45 Gray which was to be delivered in 5 fractions. Two PTVs were created with a margin of 3.0 mm to IGTV. Considering the positions of the lesions, a single isocentre plan was created using a 6MV FFF photon beam for both the PTVs with the VMAT technique. The treatment was carried through with 3 arcs, one coplanar, and the other 2 non-coplanar. At the time of treatment, after the proper positioning of the patient, one CBCT image was taken to match with the planned CT image acquired at the time of the simulation. After applying the translational and rotational errors, the patient was treated.
The patient was treated successfully. After treatment, the condition of the patient was normal, and no toxicities have been observed in follow-up.
Mono isocentric VMAT planning can be used for closely spaced lesions considering the position of lesions and other normal structures in the vicinity.
摘要：
背景：肝细胞癌（HCC）是全球癌症死亡的第二大常见原因。与HCC发展相关的危险因素是慢性乙型肝炎，丙型肝炎,和酒精性肝硬化。HCC的标准治疗是手术切除，但对于某些患者范围有限。放射治疗的不断进步使立体定向放射治疗（SBRT）技术成为治疗无法进行手术的病例的一种选择。根据最近的文献和荟萃分析，SBRT是一种具有高局部控制和低毒性的最佳治疗方法。在SBRT中,与传统辐射相比，辐射的分数较少，并且在图像引导的帮助下采用高精度的传输和准确性。从一系列回顾性和前瞻性研究中，已经证实，SBRT在早期不能手术的患者中实现了良好的局部控制，中间阶段,和晚期疾病。
背景：一名42岁的男性患者与HBeAg感染和高AFP水平发展为HCCBCLCA期入院。有两个病变的PTV体积为41.07cc和9.573cc，它们之间的距离为3.51cm。这两个病变均采用SBRT技术进行单中心VMAT计划治疗。在这种情况下,我们提出了一种不寻常的单等中心治疗计划的临床实践，用于治疗多发性肝脏病变。由于放射治疗被视为主要的治疗形式，因为患者不是理想的手术候选人，选择SBRT作为患者的主要治疗方式，因为两个病变的体积很小，肝脏体积正常（>700cc）。进行三阶段4DCT进行模拟，以考虑目标体积和正常结构的运动。在描绘目标体积和其他正常结构后，治疗计划以45Gray的剂量进行，分5次进行。创建两个PTV,其与IGTV的边缘为3.0mm。考虑到病变的位置，使用VMAT技术为两个PTV使用6MVFFF光子束创建了单个等中心计划。治疗是用3个弧进行的，一个共面的,和其他2个非共面。在治疗的时候,在正确定位病人后，拍摄一张CBCT图像,以与模拟时采集的计划CT图像相匹配。应用平移和旋转误差后，病人得到了治疗。
结果：患者治疗成功。治疗后,病人情况正常,在随访中没有观察到毒性。
结论：单等中心VMAT计划可用于考虑病变位置和附近其他正常结构的紧密间隔病变。
背景：一名42岁的男性患者与HBeAg感染和高AFP水平发展为HCCBCLCA期入院。有两个病变的PTV体积为41.07cc和9.573cc，它们之间的距离为3.51cm。这两个病变均采用SBRT技术进行单中心VMAT计划治疗。在这种情况下,我们提出了一种不寻常的单等中心治疗计划的临床实践，用于治疗多发性肝脏病变。由于放射治疗被视为主要的治疗形式，因为患者不是理想的手术候选人，选择SBRT作为患者的主要治疗方式，因为两个病变的体积很小，肝脏体积正常（>700cc）。进行三阶段4DCT进行模拟，以考虑目标体积和正常结构的运动。在描绘目标体积和其他正常结构后，治疗计划以45Gray的剂量进行，分5次进行。创建两个PTV,其与IGTV的边缘为3.0mm。考虑到病变的位置，使用VMAT技术为两个PTV使用6MVFFF光子束创建了单个等中心计划。治疗是用3个弧进行的，一个共面的,和其他2个非共面。在治疗的时候,在正确定位病人后，拍摄一张CBCT图像,以与模拟时采集的计划CT图像相匹配。应用平移和旋转误差后，病人得到了治疗。
结果：患者治疗成功。治疗后,病人情况正常,在随访中没有观察到毒性。
结论：单等中心VMAT计划可用于考虑病变位置和附近其他正常结构的紧密间隔病变。
