Tumor Volume Measurement Errors of RECIST Studied With Ellipsoids
Zachary H. Levine, Benjamin R. Galloway, Adele P. Peskin, C. P. Heussel, Joseph J. Chen
RECIST (Response Evaluation Criteria in Solid Tumors) is a linear measure intended to predict tumor volume in medical computed tomography (CT). In this work, using purely geometrical considerations, we establish limits for how well RECIST can predict the volume of randomly-oriented ellipsoids and randomly-oriented tumor models, each composed of the union of ellipsoids. The principal conclusion is that a change in the reported RECIST value needs to be a factor of at least 1.2 to achieve a 95% confidence that one ellipsoid is larger than another assuming the ratio of maximum to minimum diameters is no more than 2, an assumption which is reasonable for some classes of tumors. RECIST works less well on the more realistic tumor models than on ellipsoids fitted to their second moments. There is a significant probability that RECIST will select a tumor other than the largest due to orientation effects of non-spherical tumors, amounting to 9% for previously reported liver malignoma data.
, Galloway, B.
, Peskin, A.
, Heussel, C.
and Chen, J.
Tumor Volume Measurement Errors of RECIST Studied With Ellipsoids, Medical Physics, [online], https://doi.org/10.1118/1.3577602
(Accessed December 6, 2023)