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Pseudo-Progression May Occur With
Immuno-Oncology Treatment

  • The nature of the antitumor immune response can create the appearance of disease progression, either as tumor growth or as the appearance of new lesions.1,2 This is known as pseudo-progression
    • Pseudo-progression does not reflect tumor-cell growth but may be misclassified as disease progression1,3,4
      • Tumors may appear to grow, or new lesions may appear when immune cells infiltrate the tumor site1
      • Due to the time required to mount an adaptive immune response, pseudo-progression may also reflect continued tumor growth until a sufficient response develops1,5


While uncommon, pseudo-progression is an important consideration when evaluating response to immunotherapies.5

Research is ongoing to identify additional measures that differentiate pseudo-progression from disease progression.

Immune Pathways

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research into immune
pathways is heading

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I-O Biomarkers

Read about I-O biomarkers we're currently investigating

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References–Pseudo-progression and I-O

1. Wolchok JD, Hoos A, O’Day S, et al. Guidelines for the evaluation of immune therapy activity in solid tumors: immune-related response criteria. Clin Cancer Res. 2009;15(23):7412-7420. 2. Hygino da Cruz LC Jr, Rodriguez I, Domingues RC, Gasparetto EL, Sorensen AG. AJNR Am J Neuroradiol. 2011;32(11):1978-1985. 3. Chiou VL, Burotto M. Pseudoprogression and immune-related response in solid tumors. J Clin Oncol. 2015;33(31):3541-3543. 4. Thust SC, van den Bent MJ, Smits M. Pseudoprogression of brain tumors. J Magn Reson Imaging. 2018. doi:10.1002/jmri.26171. 5. Hales RK, Banchereau J, Ribas A, et al. Assessing oncologic benefit in clinical trials of immunotherapy agents. Ann Oncol. 2010;21:1944-1951. 6. Linhares P, Carvalho B, Figueiredo R, Reis RM, Vaz R. Early pseudoprogression following chemoradiotherapy in glioblastoma patients: the value of RANO evaluation. J Oncol. 2013. doi:10.1155/2013/690585. 7. Eisenhauer EA, Therasse P, Bogaerts J, et al. New response evaluation criteria in solid tumours: revised RECIST guideline (version 1.1). Eur J Cancer. 2009;45(2):228-247.