To better inform the development of new cancer treatments, researchers from the University of Colorado Cancer Center on the Anschutz Medical Campus have developed a new method of assessing the response of cancer lesions to therapy.
New method to measure cancer lesions
A validated, widely used method called RECIST is used to measure cancer lesions and how they evolve in response to therapy. RECIST solely considers the lesion’s greatest dimension. Researchers looked into how the location of a lesion in a patient’s chest and whether or not lesions reduced more in the long versus the shortest dimensions could affect assessments of a treatment’s effectiveness. Their findings were published in the journal Clinical Lung Cancer. Lesions in the lung’s outer lining tissues or those near the heart typically shrank in breadth rather than in maximum measured length, underestimating the efficacy of treatment.
As different kinds of lung cancer have previously been linked to varying degrees of involvement of these lining tissues, this could lead to disparities in response rates, independent of any actual variations in a drug’s effectiveness.
In order to combat this, the researchers developed a unique method called MAX that makes use of two measurements of the lesions and selects the diameter (long or short) that has the biggest percentage change to be the one captured as representational of benefit.
In the study, 249 lung cancer patients with 386 lesions were evaluated using MAX, whereas over 300 lung cancer patients with 446 independently measured lesions were included for RECIST analysis. The MAX approach dramatically raised the observed response rate overall and minimized the effect of lesion location in the chest on the apparent efficacy of targeted therapy for lung cancer.
For this study, researchers focused on a particular population of patients with lung cancer treated with highly active targeted therapies, which leaves room for further investigation into the efficiency of MAX in measuring lesions in patients with various cancers and in lung cancers treated with various agents.
These findings hold promise for possibly offering a new approach to evaluating and better creating new cancer treatments. This approach may more accurately reflect a patient’s reaction to therapy.