Department of Radiation Oncology, Friedrich-Alexander-University of Erlangen-Nuernberg, Erlangen, Germany.
Radiat Oncol. 2019 Dec 31;15(1):2. doi: 10.1186/s13014-019-1444-4.
Individual radiosensitivity is influencing the outcome of radiation therapy. A general ex vivo testing is very work-intensive. It is of interest to see if a significant prediction concerning the sensitivity can be made by in vivo irradiation during radiation treatment.
Blood samples of 274 patients with rectal cancer and 43 lung cancer patients receiving radiotherapy were examined after 2 Gy ex vivo and in vivo ionizing radiation. Chromosomes # 1, 2 and 4 were stained by the 3-color-fluorescence in situ hybridization. Chromosomal aberrations were analyzed as breaks per metaphase (B/M). The deposited energy per session was calculated for each patient.
Weak correlation could be found between the chromosomal aberrations ex and in vivo. Though receiving significantly smaller deposited energy during radiation therapy (RT) the lung cancer cohort displayed B/M values similar to the rectal cancer cohort. Considering the individual deposit energy differences improved slightly the correlation.
As various factors influence the induction of chromosomal aberrations it seems not feasible to estimate individual radiosensitivity via in vivo irradiation. An ex vivo estimation of individual radiosensitivity should be preferred.
个体放射性敏感性影响放射治疗的结果。一般的体外测试非常耗费精力。人们有兴趣了解在放射治疗期间进行体内照射是否可以对敏感性做出重要预测。
对接受放射治疗的 274 例直肠癌患者和 43 例肺癌患者的血液样本进行了 2Gy 体外和体内电离辐射后检测。通过三色荧光原位杂交对染色体 #1、2 和 4 进行了染色。将中期断裂数（B/M）作为染色体畸变的分析指标。为每位患者计算了每次治疗的沉积能量。
体外和体内染色体畸变之间存在微弱的相关性。尽管肺癌组在放射治疗（RT）期间接受的沉积能量明显较小，但 B/M 值与直肠癌组相似。考虑到个体沉积能量的差异，相关性略有改善。
由于各种因素影响染色体畸变的诱导，通过体内照射来估计个体放射性敏感性似乎不可行。应优先选择体外估计个体放射性敏感性。
