[18F]FDG PET/CT Integration in Evaluating Immunotherapy for Lung Cancer: A Clinician's Practical Approach.

Area of Science:

• Oncology
• Radiology
• Nuclear Medicine

Background:

• Immune checkpoint inhibitors (ICIs) have transformed lung cancer treatment, improving survival rates.
• Assessing treatment response to immunotherapy is challenging due to non-standard patterns like pseudoprogression and hyperprogression.
• Conventional RECIST 1.1 criteria may not fully capture these complex responses.

Purpose of the Study:

• To review novel response evaluation criteria for lung cancer immunotherapy.
• To highlight the role of imaging, including [18F]FDG PET/CT, in assessing treatment response.
• To emphasize the importance of a multidisciplinary approach for optimal patient management.

Main Methods:

• Discussion of iRECIST and imRECIST criteria for RECIST-based response assessment.
• Review of metabolic response criteria for [18F]FDG PET/CT, including PERCIMT, imPERCIST, and iPERCIST.
• Emphasis on integrating imaging findings into clinical decision-making.

Main Results:

• Novel criteria (iRECIST, imRECIST, PERCIMT, imPERCIST, iPERCIST) offer improved assessment of immunotherapy response in lung cancer.
• [18F]FDG PET/CT is valuable for detecting pseudoprogression and other unconventional responses.
• Multidisciplinary collaboration is key to interpreting complex response patterns.

Conclusions:

• Advanced imaging and updated criteria are essential for accurately evaluating lung cancer patients on immunotherapy.
• Effective interpretation requires collaboration between oncologists, radiologists, and nuclear medicine specialists.
• This review provides guidance for clinicians managing lung cancer in the era of immunotherapy.