ICD-10 Code C49.A – Gastrointestinal stromal tumor (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C49.A – Gastrointestinal stromal tumor
What it is
C49.A identifies a gastrointestinal stromal tumor, a mesenchymal neoplasm arising in the digestive tract. Use it when the record documents a GIST or gastrointestinal stromal tumor.
Clinical signs
Clinical features vary; refer to documentation. Commonly noted findings include an abdominal mass, gastrointestinal bleeding, pain, or incidental imaging discovery, but diagnosis should be supported by pathology or specialist assessment.
When to use this code
Use C49.A when the provider documents a gastrointestinal stromal tumor of the stomach, small intestine, colon, or another GI site. It also applies when the note states GIST without a more specific anatomic or histologic code. Do not code from suspicion alone.
Do not use for
Do not use this code for other sarcomas, benign GI masses, or nonspecific abdominal tumors. If the record only says “mass” or “lesion,” check documentation before assigning C49.A.
Coding tip
Confirm the exact tumor wording and site in the pathology or operative report before coding.