If orthotopic PDX models are superior to subcutaneous PDX models, why does the industry still rely so heavily on subcutaneous PDX models?

While orthotopic PDX have gained prominence in basic and translational cancer research over the last decade, the industry continues to rely heavily on subcutaneous PDX models because they are not only easier to implant, but also more readily accessible under the skin.1 This makes subcutaneous PDX tumors easier to measure by traditional, manual caliper measurement than O-PDX models. However, manual measurement is inherently prone to variability and inconsistencies introduced by analyst technique and skill. That subjectivity can dramatically influence scientific conclusions.2 3

At Certis, we believe fighting cancer warrants a more clinically relevant model and more precise measurements. That is why we use O-PDX models, combined with advanced imaging, including a murine-scale MRI for tumor volume measurements, and sophisticated analytical tools for phenotypic characterization, protein expression and tumor morphology identification.

1 Lai Y, Wei X, Lin S, Qin L, Cheng L, Li P. Current Status and Perspectives of Patient-Derived Xenograft Models in Cancer Research. J Hematol Oncol. 2017;10(1):106.
2 Kersemans V, Cornelissen B, Allen PD, Beech JS, Smart SC. Subcutaneous Tumor Volume Measurement in the Awake, Manually Restrained Mouse Using MRI. J Magn Reson Imaging. 2013;37(6):1499-1504.
3 Ayers GD, McKinley ET, Zhao P, et al. Volume of Preclinical Xenograft Tumors is More Accurately Assessed by Ultrasound Imaging than Manual Caliper Measurements. J Ultrasound Med. 2010;29(6):891-901.