CAR T-cell therapy induced pseudoprogression.

Area of Science:

• Oncology
• Immunology
• Radiology

Background:

• Pseudoprogression is a post-therapy increase in tumor burden on imaging, later resolving without further treatment.
• Initially observed with checkpoint inhibitors for solid tumors, it stems from immunological responses.
• Chimeric antigen receptor (CAR) T-cell therapy for hematologic malignancies can also induce pseudoprogression (CARTiPP).

Purpose of the Study:

• To review the emergence of pseudoprogression in immunotherapy, specifically CAR T-cell induced pseudoprogression (CARTiPP).
• To discuss diagnostic challenges and radiologic guideline modifications for interpreting CARTiPP.
• To explore the limited data on CARTiPP within the tumor microenvironment and its clinical implications.

Main Methods:

• Literature review of pseudoprogression in immunotherapy.
• Analysis of radiologic imaging interpretation in the context of CAR T-cell therapy.
• Discussion of clinical complications and management strategies for CARTiPP.

Main Results:

• Pseudoprogression is an underreported, rare adverse event associated with CAR T-cell therapy.
• CARTiPP can complicate response assessment and lead to organ compression due to edema.
• Modified radiologic guidelines are essential for accurate scan interpretation.

Conclusions:

• CARTiPP presents unique challenges in managing hematologic malignancies treated with CAR T-cell therapy.
• Further research is needed on the tumor microenvironment's role in CARTiPP.
• Clearer diagnostic and management guidelines are required for this adverse event.