Drug-induced Sarcoid-like Reaction Presenting as Fascitis.

Area of Science:

• Oncology
• Radiology
• Immunology

Background:

• Drug-induced sarcoid-like reactions (DISRs) pose clinical management challenges.
• Commonly present as lymphadenopathy, spleen, and bone involvement on FDG-PET/CT.
• DISR presenting as fasciitis/myofasciitis is exceptionally rare.

Purpose of the Study:

• To discuss pre-chemo, post-chemo, and follow-up FDG-PET/CT scans in DISR-induced fasciitis.
• To illustrate the resolution of DISR findings after immunotherapy cessation.
• To explore diagnostic and management strategies for DISR.

Main Methods:

• Analysis of serial FDG-PET/CT scans.
• Correlation with immunotherapy treatment and cessation.
• Review of diagnostic criteria including histology and follow-up imaging.

Main Results:

• FDG-PET/CT demonstrated DISR-induced fasciitis.
• Resolution of fasciitis and other findings occurred after stopping immunotherapy.
• Diagnostic approaches involve histologic confirmation or imaging follow-up.

Conclusions:

• DISR-induced fasciitis is a rare manifestation requiring careful diagnosis.
• Serial FDG-PET/CT imaging is crucial for monitoring response to immunotherapy cessation.
• Management decisions depend on symptom severity and diagnostic certainty.