Pseudoprogression and Hyperprogression as New Forms of Response to Immunotherapy

Area of Science:

• Oncology
• Immunotherapy
• Cancer Research

Background:

• Immunotherapy indications in oncology are expanding.
• Unconventional responses like pseudoprogression and hyperprogression are observed.
• Consensus on definitions and clinical impact is lacking.

Purpose of the Study:

• To review data on pseudoprogression and hyperprogression.
• To focus on definitions, incidence, predictive factors, and biological mechanisms.
• To explore methods for distinguishing these phenomena.

Main Methods:

• Literature review of existing data on pseudoprogression and hyperprogression.
• Analysis of reported incidence, predictive factors, and biological mechanisms.
• Examination of radiological and biological methods for differentiation.

Main Results:

• Pseudoprogression incidence ranges from 0-15%.
• Hyperprogression incidence ranges from 4-29%, often correlating with worse survival.
• Both phenomena occur across various cancer types.
• Radiomics and ctDNA/cfDNA are potential distinguishing methods needing validation.

Conclusions:

• Pseudoprogression and hyperprogression are frequent immunotherapy responses.
• Better characterization is needed for improved cancer patient management.
• Treatment beyond progression requires caution and monitoring; hyperprogression necessitates early immunotherapy cessation.