Image-guided radiation therapy using magnetic resonance imaging (MRI) is a new technology that has been widely studied and developed in recent years. The technology combines the advantages of MRI imaging, and can offer online real-time tracking of tumor and adjacent organs at risk, as well as real-time optimization of radiotherapy plan. In order to provide a comprehensive understanding of this technology, and to grasp the international development and trends in this field, this paper reviews and summarizes related researches, so as to make the researchers and clinical personnel in this field to understand recent status of this technology, and carry out corresponding researches. This paper summarizes the advantages of MRI and the research progress of MRI linear accelerator (MR-Linac), online guidance, adaptive optimization, and dosimetry-related research. Possible development direction of these technologies in the future is also discussed. It is expected that this review can provide a certain reference value for clinician and related researchers to understand the research progress in the field.
Objective To evaluate the effectiveness and prognosis of patients in advanced hepatocellular carcinoma (HCC) with portal vein (PV) tumor thrombus received external-beam radiation therapy (EBRT). Methods The clinical data of 126 HCC patients with PV tumor thrombus who were referred for EBRT at our institution from January 2000 to November 2009 were analyzed retrospectively. EBRT was designed to focus on the tumor thrombus with or without primary intrahepatic tumors， to deliver a median total conventional dose of 50 Gy (range of 30-60 Gy). Predictors of survival were identified using univariate and multivariate analysis. Results Unfavorable pretreatment predictors were associated by multivariate analysis with lower albumin and higher α-fetoprotein levels, poorer Child-Pugh liver function classification, poorer intrahepatic tumor control， lymph node metastases， and the two-dimensional EBRT technique. The dose of EBRT showed no significant in both univariate and multivariate survival analysis. Conclusions In patients with HCC， EBRT is effectively prevents progression in cases of PV tumor thrombus， but palliative dose of EBRT is not related to survival.EBRT is not related to survival.
ObjectiveTo investigate the effect of Yttrium-90 selective internal radiotherapy (90Y-SIRT) on tumor control and compensatory hyperplasia of left hepatic lobe in the treatment of right hepatic malignant tumor. MethodsThe clinical data of 134 patients with liver malignant tumor (primary or secondary) who were treated with 90Y-SIRT in the Department of Hepatobiliary and Pancreatic Surgery, Beijing Tsinghua Changgung Hospital from September 2022 to November 2023 were collected, and 29 patients who met the inclusion and exclusion criteria were analyzed retrospectively. The liver volume, tumor volume, postoperative future liver remnant (FLR) and the percentage of FLR proliferation before and after treatment were measured by CT or MRI, and the surgical resection rate and pathological necrosis rate of tumor focus after 90Y-SIRT treatment were analyzed. The liver volume, tumor volume, postoperative future liver remnant (FLR) and the percentage of FLR hyperplasia were measured by CT or MRI before and 1 and 3 months after 90Y-SIRT, and the surgical resection rate and pathological necrosis rate of tumor lesions after 90Y-SIRT treatment were analyzed. ResultsOf the 29 patients, 22 patients with hepatocellular carcinoma, 2 patients with cholangiocarcinoma and 5 patients with liver metastases from colorectal cancer received 90Y-SIRT of the right liver. At 1 and 3 months after treatment, the tumor volume average decreased by 149.2 mL (P=0.124) and 228.2 mL (P=0.012), the right liver volume was average reduced by 197.4 mL (P=0.026) and 318.6 mL (P=0.023), the left liver volume average increased by 64.9 mL (P=0.261) and 144.7 mL (P=0.124), and the percentage of FLR increased by 6.6% (P=0.018) and 13.4% (P＜0.001) of 29 patients, respectively. Three months after operation, mRECIST standard was used to evaluate the curative effect of tumor imaging. The results showed that the objective response rate of tumor was 79.3% and the disease control rate was 93.1%. Conclusions90Y-SIRT can effectively control the growth of malignant tumors in the right lobe of the liver and induce compensatory hyperplasia of the left liver. At the same time, high objective response rate and pathological necrosis rate of tumor lesions can be obtained.
With the publication of several phase Ⅱ and Ⅲ clinical studies, the multidisciplinary diagnostic and therapeutic strategies for early resectable non-small cell lung cancer (rNSCLC) are rapidly evolving. These studies have elucidated the significant effects of neoadjuvant and adjuvant therapies on improving the prognosis of rNSCLC patients, while also highlighting the urgent need to revise and refine corresponding treatment protocols and clinical pathways. In response, the International Association for the Study of Lung Cancer has assembled a diverse, multidisciplinary international expert panel to evaluate current clinical trials related to rNSCLC and to provide diagnostic, staging, and treatment recommendations for rNSCLC patients in accordance with the 8th edition of the AJCC-UICC staging system. The consensus recommendations titled "Neoadjuvant and adjuvant treatments for early stage resectable non-small cell lung cancer: Consensus recommendations from the International Associationfor the Study of Lung Cancer" outline 20 recommendations, 19 of which received over 85% agreement from the experts. The recommendations indicate that early rNSCLC patients should undergo evaluation by a multidisciplinary team and complete necessary imaging studies. For stage Ⅱ patients, consideration should be given to either adjuvant therapy following surgery or direct neoadjuvant/perioperative treatment, while stage Ⅲ patients are recommended to receive neoadjuvant chemoimmunotherapy followed by surgery. Postoperatively, adjuvant immunotherapy should be considered based on the expression levels of programmed cell death ligand 1, along with testing for other oncogenic driver mutations. For patients with epidermal growth factor receptor or anaplastic lymphoma kinase mutations sensitive to tyrosine kinase inhibitors, corresponding adjuvant targeted therapy is recommended. These recommendations aim to provide personalized and precise treatment strategies for early rNSCLC patients to enhance the efficacy of neoadjuvant and adjuvant therapies. This article provides an in-depth interpretation of these consensus recommendations.
The dose data produced by treatment plan system (TPS) in intensity-modulated radiation therapy (IMRT) has many gradient edge points. Considering this feature we proposed a new interpolation algorithm called treatment plan dose interpolation algorithm based on gradient feature in intensity-modulated radiation therapy (TDAGI), which improves the Canny algorithm to detect the gradient edge points and non-edge points by using the gradient information in the dose data plane. For each gradient edge point, the corresponding gradient profile was traced and the profile's sharpness was calculated, and for each non-edge point, the dispersion was calculated. With the sharpness or dispersion, the kernel coefficients of bi-cubic interpolation can be obtained and can be used as the central point to complete the bi-cubic interpolation calculation. Compared with bi-cubic interpolation and bilinear interpolation, the TDAGI algorithm is more accurate. Furthermore, the TDAGI algorithm has the advantage of gradient keeping. Therefore, TDAGI can be used as an alternative method in the dose interpolation of TPS in IMRT.
ObjectiveTo summarize clinical application progress of stereotactic radiotherapy for primary hepatocellular carcinoma. MethodsThe literatures about the research progress of the stereotactic radiotherapy for primary hepatocellular carcinoma were reviewed. ResultsRadiotherapy for hepatocellular carcinoma is importantly based on the radiation biology of the liver and the radiophysics of the liver cancer. Stereotactic precision radiotherapy is an effective and low toxic treatment for early hepatocellular carcinoma, moreover, it alone or in combination with microwave ablation, hepatic artery chemoembolization for unresectable hepatocellular carcinoma is safe and effective method for the treatment. ConclusionsThe optimal dose model for hepatocellular carcinoma, hepatocellular carcinoma radical dose level are problems that need further exploration, and radiobiology, radiation physics research must be strengthened to explore it, stereotactic precision radiotherapy treatment modalities in the treatment of hepatocellular carcinoma position will become increasingly people attention.
Objective To overview the systematic reviews of the effectiveness and safety of the charged-particle radiation therapy. Methods Databases including CNKI, WanFang Data, PubMed, and EMbase were electronically searched from January 2007 to November 2020. Two investigators independently screened literature, extracted data, and assessed the quality of the included studies by AMSTAR 2, and then reported results through a narrative synthesis of outcomes. Results A total of 6 systematic reviews were identified. One systematic review demonstrated moderate quality and the other 5 demonstrated critically low quality. The charged-particle radiation therapy had a wide range of applications. Its effectiveness was superior to traditional radiotherapy methods on various types of tumors in various regions of the body, with acceptable side effects. Specifically, the effectiveness and safety outcomes of carbon ion radiotherapy was superior to those of proton radiotherapy. Conclusions Current evidence shows that the charged-particle radiation therapy has superior effectiveness and limited toxicity, though the studies are of relatively low quality. High quality and larger sample size researches are required in the future.
ObjectiveTo discuss the clinical value of internal radiation therapy with hepatic intraarterial iodine131 labeled material for the treatment of hepatocellular carcinoma (HCC). MethodsThis summarized paper was made on literature review. ResultsIodine131lipiodol and several reported iodine131labeled antibodies to HCC associated antigens were concentrated in the foci of HCC with a high tumortonormaltissue absorbed dose ratios. No severe side effects occurred. It was used in various kinds of HCC patients, and mostly showed a significant tumor response. Survival rate of HCC patients was raised in several clinical trials.Conclusion Internal radiotherapy with hepatic intraarterial iodine131 labeled material may be considered as an effective method to treat HCC.
ObjectiveTo evaluate the effect of post mastectomy radiation therapy (PMRT) on breast reconstruction after mastectomy in breast cancer patients, in order to provide evidence support for clinical treatment decision.MethodsFive databases searched in the current study include the Cochrane Library, PubMed, CNKI, VIP and WanFang database. A systematic search for control trials was performed in each database from the starting date of each database to March 1, 2021. After the two evaluators independently selected literatures, extracted data and conducted quality evaluation according to the inclusion and exclusion criteria, the meta analysis was carried out by Revman 5.3 software.ResultsA total of 9 cohort studies (3 447 cases) were included, including 699 cases in PMRT group and2 748 cases in non-radiotherapy group. The results of meta-analysis showed that: PMRT was associated with significant increase in capsular contracture. The incidence of capsular contracture increased from 4.34% in the non-radiotherapy group to 34.10% in patients receiving PMRT [OR=9.25, 95%CI (3.76, 22.78), P<0.000 01]. In addition, PMRT was associated with a significant increase in incidences of reconstructive failure [OR=2.55, 95%CI (1.74, 3.74), P<0.000 01] and revisional surgery [OR=2.24, 95%CI (1.58, 3.18), P<0.000 01]. Moreover it was associated with a significant reduction in patient satisfaction [OR=0.29, 95%CI (0.15, 0.57), P=0.000 30] and cosmetic outcome [OR=0.26, 95%CI (0.15, 0.43), P<0.000 01].ConclusionThis meta-analysis demonstrates that breast cancer patients who received PMRT after breast reconstruction, the rate of adverse events is increased and patients’ satisfaction and cosmetic outcome are decreased.
ObjectiveTo compare the static intensity-modulated radiation therapy (IMRT) plans using different beams sets and segments number, and find the better static IMRT plan sets on beams and segments in gastric surgical adjuvant radiotherapy.MethodsFifteen patients who underwent adjuvant radiotherapy for gastric cancer between February 1st and August 30th, 2013 were chosen as subjects through random sampling. Based on the 5 beams static IMRT plans already used in clinical practice, four different static IMRT plans used diverse beams sets for each patient were designed in the same treatment planning system (Pinnacle 9.2). The beams sets of static IMRT plans were as follows: 7 coplanar equal beams; 5 coplanar equal beams; 4 coplanar beams of 310, 20, 90 and 180°; 3 coplanar beams of 310, 65 and 180°. Sufficient segments 65 was set as the max segments number in order to compare the plans’ difference just resulting from beams. In the second step, the max segments number was changed from 65 to 45 and 25 to design two different static IMRT plans for the 4 coplanar beams static IMRT plans. The dosimetric parameters were compared for the planning target volume (PTV) and organs at risk (OARs). The monitor units and treatment times of the different static IMRT plans were also evaluated.ResultsWhen the max segments number was set to 65, the 4 coplanar beams static IMRT plans were a little better on PTV conformability than the 5 coplanar beams static IMRT plans used in clinical practice (0.74±0.04 vs. 0.73±0.05, P<0.01). Meanwhile, better OARs dose sparing especially for liver and kidneys were gained by the 4 coplanar beams static IMRT plans, for example, the percent volume gained 30 Gy for liver [(22.71±6.10)%vs. (24.03±6.84)%, P<0.01] and the percent volume gained 20 Gy for the right kidney [(14.97±6.72)%vs. (19.41±6.14)%, P<0.01]. The PTV conformability of the 4 coplanar beams static IMRT plans reduced as the max segments number became smaller (0.74±0.04vs. 0.73±0.04 vs. 0.71±0.04, P<0.05). However, they were still acceptable in clinical practice. And the better dose sparing for liver and kidneys were retained. The average reductions of 1.8 and 4.3 minutes on the irradiation time were get by the 4 coplanar beams static IMRT plans with the max segments number 45 and 25 compared to that with the max segments number 65 [(494.66±26.79)vs. (384.26±14.99) vs. (235.00±9.21) s, P<0.01]. And the raises of treatment efficiency were 22.3% and 52.4%, respectively (P<0.05).ConclusionsThe 4 coplanar beams static IMRT plans with fewer segments could ensure plan quality, and protect the OARs better in the meanwhile, especially for liver and kidneys. The treatment time is reduced as well. The 4 coplanar beams static IMRT plans could improve the treatment efficiency.