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Published on: November 26, 2010
Immune checkpoint inhibitor-associated lymphocytic colitis in a patient with metastatic melanoma
Reem Matar1, Khalid Abu Zeinah1, Tanish Modi1
1Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA.
Insights
This case study details a patient with metastatic melanoma experiencing severe diarrhea. The condition was diagnosed as lymphocytic colitis, challenging to distinguish from targeted therapy side effects, requiring endoscopic confirmation.
Area of Science:
- Oncology
- Gastroenterology
- Immunology
Background:
- Metastatic melanoma treatment involves targeted therapies and immunotherapies.
- Immune checkpoint inhibitors (ICIs) can cause immune-related adverse events, including colitis.
- Distinguishing ICI-induced colitis from other causes is clinically significant.
Purpose of the Study:
- To report a case of lymphocytic colitis in a patient receiving combination therapy for metastatic melanoma.
- To highlight the diagnostic challenges in differentiating immune-related adverse events from targeted therapy side effects.
- To emphasize the role of endoscopic and histological findings in guiding treatment.
Main Methods:
- Case report of a patient with metastatic melanoma on encorafenib/binimetinib and nivolumab/relatlimab.
- Clinical presentation of acute-onset nausea, vomiting, and watery diarrhea.
- Diagnostic workup including exclusion of infectious causes, flexible sigmoidoscopy, and biopsy.
Main Results:
- Infectious causes of diarrhea were excluded.
- Flexible sigmoidoscopy with biopsy confirmed lymphocytic colitis.
- Symptoms persisted despite cessation of BRAF-MEK therapy, necessitating escalated immunosuppressive treatment.
Conclusions:
- Differentiating immune checkpoint inhibitor-mediated colitis from targeted therapy adverse events presents diagnostic challenges.
- Endoscopic and histological confirmation are crucial for accurate diagnosis and appropriate management.
- This case underscores the complexity of managing gastrointestinal adverse events in patients on combined immunotherapies and targeted agents.
Abstract:
We describe the case of a man in his 60s with metastatic melanoma on encorafenib/binimetinib and nivolumab/relatlimab, with a history of immune checkpoint inhibitor (ICI)-induced acute interstitial nephritis, who presented with acute-onset nausea, vomiting and profuse watery diarrhoea. Investigations excluded infectious causes, and flexible sigmoidoscopy with biopsy demonstrated lymphocytic colitis. His symptoms persisted despite discontinuation of Braftovi-Mektovi (BRAF-MEK) therapy and required escalation of corticosteroid therapy and budesonide initiation. This case highlights the diagnostic challenges of differentiating ICI-mediated colitis from adverse events of targeted therapy and underscores the importance of endoscopic and histological confirmation in guiding treatment.
