Symptomatic pseudoprogression in metastatic colorectal cancer

Area of Science:

• Oncology
• Immunotherapy
• Colorectal Cancer Research

Background:

• Metastatic colorectal cancer (mCRC) poses significant treatment challenges.
• Immunotherapy, such as pembrolizumab, offers a new avenue for mCRC treatment.
• Accurate assessment of treatment response is crucial for optimizing patient outcomes.

Observation:

• A patient with mCRC experienced worsening symptoms and increased tumor size after two cycles of pembrolizumab.
• Clinical decline and radiographic findings raised concerns for disease progression, prompting consideration of hospice care.
• Pseudoprogression, a phenomenon where initial signs of progression are followed by response, was considered.

Findings:

• Despite initial concerns, a third cycle of pembrolizumab was administered.
• The patient demonstrated marked symptomatic improvement and a reduction in tumor mass.
• Radiological assessments confirmed sustained improvement with continued immunotherapy.

Implications:

• This case underscores the importance of recognizing pseudoprogression in patients receiving immunotherapy for mCRC.
• Distinguishing pseudoprogression from true disease progression is critical for appropriate treatment continuation.
• Careful monitoring and consideration of alternative treatment effects can lead to improved patient management and outcomes in mCRC.