Reconstitution of internal target volumes by combining four-dimensional computed tomography and a modified slow computed tomography scan in stereotactic body radiotherapy planning for lung cancer

3区 · 医学

ArticleOA

作者: Young Jun Yang ; Gil Ja Huh ; Hae Nam Chung ; Po Song Yang ; Seong Soon Jang ; Eun Youn Cho ; Jae Hyuk Seo ; Ji Chan Park ; Suk Young Park

BACKGROUNDTo evaluate the volumetric and geometric differences in the ITVs generated by four-dimensional (4D) computed tomography (CT), a modified slow CT scan, and a combination of these CT methods in lung cancer patients treated with stereotactic body radiotherapy (SBRT).METHODSBoth 4D CT and modified slow CT using a multi-slice CT scanner were performed for SBRT planning in 14 patients with 15 pulmonary targets. Volumetric and geometric analyses were performed for (1) ITVall, generated by combining the gross tumor volumes (GTVs) from all 8 phases of the 4D CT; (2) ITV2, generated by combining the GTVs from 2 extreme phases of the 4D CT; (3) ITVslow, derived from the GTV on the modified slow CT scan; (4) ITVall+slow, generated by combining ITVall and ITVslow; and (5) ITV2+slow, generated by combining ITV2 and ITVslow. Three SBRT plans were performed using 3 ITVs to assess the dosimetric effects on normal lung caused by the various target volumes.RESULTSITVall (11.8 ± 8.3 cm3) was significantly smaller than ITVall+slow (12.5 ± 8.9 cm3), with mean values of 5.8% for the percentage volume difference, and a mean of 7.5% of ITVslow was not encompassed in ITVall. The geometric coverages of ITV2 and ITVslow for ITVall were 84.7 ± 6.6% and 76.2 ± 9.3%, respectively, but the coverage for ITVall increased to 90.9 ± 5.9% by using the composite of these two ITVs. There were statistically significant increases in the lung-dose parameters of the plans based on ITVall+slow compared to the plans based on ITVall or ITV2+slow. However, the magnitudes of these differences were relatively small, with a value of less than 3% in all dosimetric parameters.CONCLUSIONSDue to its ability to provides additional motion information, the combination of 4D CT and a modified slow CT scan in SBRT planning for lung cancer can be used to reduce possible errors in true target delineation caused by breathing pattern variations.

2014-09-01·International Journal of Radiation Oncology*Biology*Physics2区 · 医学

Determination of Internal Target Volume for Radiation Treatment Planning of Esophageal Cancer by Using 4-Dimensional Computed Tomography (4DCT)

2区 · 医学

Article

作者: Elizabeth Gore ; X. Allen Li ; Haijun Lu ; Xiaojian Chen ; Candice Johnstone ; An Tai

PURPOSETo determine an efficient strategy for the generation of the internal target volume (ITV) for radiation treatment planning for esophageal cancer using 4-dimensional computed tomography (4DCT).METHODS AND MATERIALS4DCT sets acquired for 20 patients with esophageal carcinoma were analyzed. Each of the 4DCT sets was binned into 10 respiratory phases. For each patient, the gross tumor volume (GTV) was delineated on the 4DCT set at each phase. Various strategies to derive ITV were explored, including the volume from the maximum intensity projection (MIP; ITV_MIP), unions of the GTVs from selected multiple phases ITV2 (0% and 50% phases), ITV3 (ITV2 plus 80%), and ITV4 (ITV3 plus 60%), as well as the volumes expanded from ITV2 and ITV3 with a uniform margin. These ITVs were compared to ITV10 (the union of the GTVs for all 10 phases) and the differences were measured with the overlap ratio (OR) and relative volume ratio (RVR) relative to ITV10 (ITVx/ITV10).RESULTSFor all patients studied, the average GTV from a single phase was 84.9% of ITV10. The average ORs were 91.2%, 91.3%, 94.5%, and 96.4% for ITV_MIP, ITV2, ITV3, and ITV4, respectively. Low ORs were associated with irregular breathing patterns. ITV3s plus 1 mm uniform margins (ITV3+1) led to an average OR of 98.1% and an average RVR of 106.4%.CONCLUSIONSThe ITV generated directly from MIP underestimates the range of the respiration motion for esophageal cancer. The ITV generated from 3 phases (ITV3) may be used for regular breathers, whereas the ITV generated from 4 phases (ITV4) or ITV3 plus a 1-mm uniform margin may be applied for irregular breathers.

2013-08-01·Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica

[Diversity changes of TCRVbeta gene in AIDS patients with incomplete immune reconstitution and influence of drug].

Article

作者: Liu, Yong-Mei ; Wang, Jie ; Tang, Yan-Li ; Li, Yong

OBJECTIVETo discuss the drug intervention in diversity changes of TCRVbeta gene in AIDS patients with incomplete immune reconstitution.METHODPBMCs were isolated from 37 cases of AIDS patients failure to immune reconstitution before and after treatment with Immune 2 and 15 cases of HIV negative healthy donors. The human gene TCRVbeta CDR3 diversity quantitative detection reagent box were used, and mapped the distribution of gene scanning and calculated different CDR3 fragme of each Vbeta family size.RESULT(1) Gaussian distribution of TCRVbeta families in patients with incomplete immune reconstitution after one year of HAART, had been broken with the occurrence of the offset TCR lineage. After six months of treatment of traditional Chinese medicine combined HAART, the TCR lineage has been partially restored. (2) Evaluated by the D (distance) value calculated by a quantitative analysis software which the kit provides, there were no significant difference in D value change between the two groups, but with traditional Chinese medicine can reduce the data variability. (3) CD4+ T cell counts had a significant correlation (r = -0.772, P = 0.000) with TCRVbeta genetic diversity.CONCLUSIONStudy of the mechanism showed oligoclonal of TCRVbeta family can get recovery in some degrees after treated by Immune 2 plus HAART, suggesting that the medicine may promote T-cell receptor gene rearrangement, helping immune cells to effectively identify the virus to reduce T-cell apoptosis.

100 项与 ITV-2 相关的药物交易

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