Measuring Response in Solid Tumors: Unidimensional Versus Bidimensional Measurement

Abstract

Background: Tumor shrinkage is a common end point used in screening new cytotoxic agents. The standard World Health Organization criterion for partial response is a 50% or more decrease in the sum of the products of two measurements (the maximum diameter of a tumor and the largest diameter perpendicular to this maximum diameter) of individual tumors. However, theoretically, the simple sum of the maximum diameters of individual tumors is more linearly related to cell kill than is the sum of the bidimensional products. It has been hypothesized that the calculation of bidimensional products is unnecessary, and a 30% decrease in the sum of maximum diameters of individual tumors (assuming spherical shape and equivalence to a 50% reduction in the sum of the bidimensional products) was proposed as a new criterion. We have applied the standard response and the new response criteria to the same data to determine whether the same number of responses in the same patients would result. Methods: Data from 569 patients included in eight studies of a variety of cancers were reanalyzed. The two response criteria were separately applied, and the results were compared using the statistic. The importance of confirmatory measurements and the frequency of nonspherical tumors were also examined. In addition, for a subset of 128 patients, a unidimensional criterion for disease progression (30% increase in the sum of maximum diameters) was applied and compared with the standard definition of a 25% increase in the sum of the bidimensional products. Results: Agreement between the unidimensional and bidimensional criteria was generally found to be good. The statistic for concordance for overall response was 0.95. Conclusion: We conclude that one dimensional measurement of tumor maximum diameter may be sufficient

Significance of and problems in adopting response evaluation criteria in solid tumor RECIST for assessing anticancer effects of advanced gastric cancer

“…Actually, the response evaluation with RECIST is extremely simple and we could not show any significant differences between the evaluation results (overall response rate and survival) with the WHO criteria and those with RECIST, in measurable lesions of 20 mm or more. This should clearly indicate the validity of the RECIST and the uselessness of two-dimensional measurements, as pointed out by James et al [8].…”

Stepwise evolution from a focal pure pulmonary ground-glass opacity nodule into an invasive lung adenocarcinoma: An observation for more than 10 years

“…Although three-dimensional volume measurements have been advocated as reliable methods particularly for the evaluation of solid nodules, until now, there have been few data supporting the use of this approach for GGO nodules. In general, the one dimensional measurement of tumor maximum diameter has been considered sufficient for assessing changes in tumor volume and ascertaining reproducibility especially for solid tumors [8]. Moreover, according to RECIST introduced in 2000 [9], tumor size measurements are conducted by the use of uni-dimensional method.…”

Gene expression in Sinclair swine with malignant melanoma

“…More information on this population and historical records can be found in Gomez-Raya et al (2009). In this study, length was used as a criterion for estimating tumor size based on James et al (1999), who concluded that unidimensional measurements for tumors are appropriate for estimating regression in solid tumors. Pigs whose tumors had reached the maximum length at collection time were considered as progressing animals.…”