324. Int J Radiat Oncol Biol Phys.

324. Int J Radiat Oncol Biol Phys. 2000 Dec 1;48(5):1539-48.

In-field and out-of-field effects in partial volume lung irradiation in rodents:
possible correlation between early dna damage and functional endpoints.

Moiseenko VV(1), Battista JJ, Hill RP, Travis EL, Van Dyk J.

Author information:
(1)London Regional Cancer Centre, University of Western Ontario, London, Ontario,
Canada.

PURPOSE: Recent observations have shown that there are regional variations in
radiation response in mouse lung as measured by functional assays. Furthermore,
there are both in-field and out-of-field effects in radiation-induced lung damage
as observed by DNA assay in rats. The purpose of this work is: (a) to examine
mice lethality data following partial volume lung irradiation to assess the
possibility of directional or regional effects, (b) to evaluate the correlation
between mice lethality data and DNA damage assayed by micronuclei production in
rat lung, and (c) to re-interpret mice lethality considering the existence of
directional effects in lung cellular response to partial volume irradiation.
METHODS AND MATERIALS: The lethality data for mice, generated at the M. D.
Anderson Cancer Center, Houston, and micronuclei yield data for rats obtained at
Princess Margaret Hospital, Toronto, were used. A radiobiological model that
allows for out-of-field and in-field effects for lung cell damage and lung
response was developed. This model is based on the observation of DNA damage in
shielded parts of rat lung that was assumed relevant to cell lethality and
consequently overall lung response.
RESULTS: While the experimental data indicated directional or regional volume
effects, the applicability of dose and volume as sole predictors of lung response
to radiation was found to be unreliable for lower lung (base) irradiation in
mice. This conforms well to rat lung response where micronuclei were observed in
shielded apical parts of lung following base irradiation. The radiobiological
model, which was specifically developed to account for the lung response outside
of primary irradiated volume, provides a good fit to mice lethality data, using
parameters inferred from rat micronuclei data.
CONCLUSION: Response to lung irradiation in rodents, in particular, elevated
sensitivity to base irradiation, can be interpreted with a hypothesis of in-field
and out-of-field effects for cellular response. If the existence of these effects
for lung is subsequently proven in humans, it will require the incorporation of
geometrical and directional information in normal tissue complication probability
calculations for lung. These considerations are ignored in present approaches
based only on conventional dose-volume histograms.

PMID: 11121660 [PubMed - indexed for MEDLINE]

結果 (中文) 3:

324。j的放射肿瘤学的生物物理。12月1日2000；48（5）：1539-48。在啮齿类动物中进行部分容积肺照射的现场和外照射效果：早期DNA损伤与功能性端点之间可能存在的相关性。Moiseenko VV（1），Battista JJ，Hill RP，Travis EL，Van Dyk J.作者信息：（1）西安大略大学伦敦区域癌症中心，伦敦，安大略，加拿大。目的：最近的观测表明，有区域的变化功能测定法测定小鼠肺的辐射响应。此外，在辐射引起的肺损伤中，无论是在现场和现场的影响通过DNA测定法观察大鼠。这项工作的目的是：（一）检查小鼠致死性数据的部分体积肺照射后，以评估定向或区域效应的可能性，（b）评估的相关性小鼠致死之间的数据和DNA损伤检测微核的产生大鼠肺，和（c）重新解释小鼠的杀伤力，考虑到存在的肺细胞对部分容积照射的定向效应。方法和材料：小鼠的致死性数据，在M D。Anderson癌症中心，休斯敦，和大鼠微核率数据获取多伦多玛格丽特公主医院，被使用。生物模型允许字段和字段对肺细胞损伤和肺的影响响应的开发。该模型是基于DNA损伤的观察大鼠肺的屏蔽部分，被认为是相关的细胞的杀伤力和因此整体肺反应。结果：实验数据表明，定向或区域体积效果、剂量和体积的适用性作为肺反应的唯一预测因子要辐射被认为是不可靠的下肺（基地）照射在老鼠.这符合大鼠肺响应，微核观察肺照射后屏蔽心尖部。放射生物学模型，这是专门开发的帐户以外的肺响应的主要照射量，提供了一个很好的适合小鼠的致死性数据，使用从大鼠微核数据推断的参数。结论：对啮齿类动物的肺辐射的反应，特别是升高对基照射的敏感性，可以解释与在现场的假设和出于对细胞反应的场效应。如果这些影响的存在对于肺随后被证明在人类，它将需要注册成立的正常组织并发症概率的几何和方向信息肺计算。这些考虑因素，在目前的方法被忽略仅基于传统的剂量体积直方图。发表于：11121660 [ PubMed索引数据库]