ABSTRACT
Objective:To compare the effect of neoadjuvant chemotherapy vs. concurrent chemoradiotherapy on the target volume and organs at risk for locally advanced bulky (>4 cm) cervical cancer. Methods:From March 1, 2019 to June 30, 2021, 146 patients pathologically diagnosed with cervical cancer were selected and randomly divided into two groups using random number table method: the neoadjuvant chemotherapy (NACT) + concurrent chemoradiotherapy (CCRT) group ( n=73) and CCRT group ( n=73). Patients in the NACT+CCRT group received 2 cycles of paclitaxel combined with cisplatin NACT, followed by CCRT, the chemotherapy regimen was the same as NACT. In the CCRT group, CCRT was given. Statistical description of categorical data was expressed by rate. The measurement data between two groups were compared by Wilcoxon rank-sum test for comparison of two independent samples, and the rate or composition ratio of two groups was compared by χ2 test. Results:Before radiotherapy, GTV in the NACT+CCRT group was (31.95±25.96) cm 3, significantly lower than (71.54±33.59) cm 3 in the CCRT group ( P<0.01). Besides, CTV and PTV in the NACT+CCRT group were also significantly lower compared with those in the CCRT group (both P<0.05). In terms of target volume dosimetry, D 100GTV, D 95CTV, V 100GTV, V 100CTV and V 95PTV in the NACT+CCRT group were significantly higher than those in the CCRT group (all P<0.05). The complete remision (CR) rates in the NACT+CCRT and CCRT groups were 86.3% and 67.6%, with statistical significance between two groups ( P<0.01) . Regarding organs at risk, NACT+CCRT group significantly reduced the dose to the bladder, rectum, small intestine and urethra compared with CCRT group (all P<0.05). Conclusions:NACT can reduce the volume of tumors in patients with large cervical masses, increase the radiation dose to tumors, reduce the dose to organs at risk, and make the three-dimensional brachytherapy easier. Therefore, NACT combined with CCRT may be a new choice for patients with locally advanced cervical cancer with large masses.
ABSTRACT
Objective:To study the effects of gantry acceleration limitations of a linear accelerator (linac) on the dosimetry of volumetric modulated arc therapy (VMAT) plans, machine efficiency, and dose verification result of VMAT plans and to explore the optimal selection of gantry motion models in the Pinnacle treatment planning system.Methods:Ten cases of nasopharyngeal carcinoma, non-small cell lung cancer, sigmoid adenocarcinoma with retroperitoneal lymph node metastasis, and invasive ductal carcinoma of the breast were each selected for this study. Then two models were set up in the Pinnacle v9.10 treatment planning system, namely the one allowing gantry acceleration and the one limiting gantry acceleration. The same field arrangement, optimized target parameters, and optimized weights of VMAT plans were adopted in the two models, in order to analyze the dosimetric variations in targets and organs at risk (OARs) and compare the differences in treatment time and gamma passing rates.Results:The treatment time of the enrolled patients under the model allowing gantry acceleration was significantly lower than that of the patients under the model limiting gantry acceleration was adopted ( t=-6.751, -0.209, -19.523, -28.999; P< 0.05) and decreased by 15.27%, 18.07%, 19.71%, and 28.75%, respectively. Meanwhile, the conformity and uniformity of target areas were affected, while there was no statistical significance in the gamma passing rates in the validation of VMAT plans ( P>0.05). For the cases of nasopharyngeal carcinoma (NPC), the maximum dose to brainstem PRV increased by 1.25%. For the cases of lung cancer, the maximum dose to the spinal cord and lung V20 increased by 1.19% and 1.21%, respectively, while lung V5 decreased by 1.21%. For the cases of sigmoid adenocarcinoma with retroperitoneal lymph node metastasis, the mean doses to bilateral kidneys, livers, small intestine, and colon all increased. For the cases of breast cancer, lung V10 on the opposite side of cancer increased by 1.66% and the mean dose to the lungs on the same side of cancer decreased by 7.45%. Conclusions:The model allowing gantry acceleration allows the treatment time to be significantly shortened and the treatment efficiency improved. Although this model had the shortcomings such as affecting the conformity and uniformity of target areas to a certain extent and increasing the doses to some OARs, clinical requirements for dosimetry were still met. Therefore, it is recommended to use the model allowing gantry acceleration in the Pinnacle planning system.
ABSTRACT
AIM: The purpose of this study is to investigate the mechanisms related to oxidized low-density lipoprotein(ox-LDL) and dendritic cells(DCs) in the process of atherosclerosis.METHODS: Human DCs were prepared from human CD14~+ peripheral blood monocytes using rhGM-CSF((100 ?g/L)) and rhIL-4(40 ?g/L).Cells were incubated with(100 mg/L) native or oxidized LDL for 72 h.The formation of foam cells was investigated by electron microscopy and oil red O staining.Phenotypic and immune functional assays were used with FACS,FITC-dextran phagocytosis,allogeneic mixed T lymphocytes reaction and secretion of Th1/Th2(IL-12/IL-2) cytokines were also conduced.RESULTS: DCs treated with ox-LDL,but not native LDL were induced into foam cells after cultured for 72 h.Compared with native LDL,ox-LDL-treated DCs were less potent in FITC-dextran phagocytosis.ox-LDL promoted allogeneic T cells proliferation.Moreover,ox-LDL upregulated CD80(72.4? 9.6 vs 89.5?10.1,P