IMMUNOHISTOCHEMISTRY, DOG-1

What this test checks

Detects DOG-1 (Discovered On GIST-1) protein, a highly specific marker for gastrointestinal stromal tumours (GIST). Used alongside CD117 to confirm GIST diagnosis.

Why do people get this test?

DOG-1 is one of the most sensitive markers for GIST, and confirming this diagnosis is critical because GIST responds to specific targeted drugs (imatinib) that are not used for other tumour types.

When you should consider this test

• When a stomach or intestinal tumour is suspected to be GIST
• When CD117 is negative but GIST is still clinically suspected
• When classifying soft tissue tumours of the abdomen

How to prepare

No preparation needed — performed on biopsy or surgical tissue.