ICD-10 Code C49.A2 – Gastrointestinal stromal tumor of stomach (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C49.A2 – Gastrointestinal stromal tumor of stomach
What it is
This code identifies a gastrointestinal stromal tumor arising in the stomach. It is a specific type of soft tissue tumor documented by site and diagnosis.
Clinical signs
Clinical features vary; refer to documentation. Commonly noted findings include a gastric mass, incidental imaging discovery, or pathology confirming a gastrointestinal stromal tumor.
When to use this code
Use C49.A2 when the provider documents a gastrointestinal stromal tumor of the stomach, including confirmed pathology or a clearly stated diagnosis. Use it for stomach-origin GISTs even if the presentation was incidental. If the record only says “GIST” without site, check documentation.
Do not use for
Do not use this code for GISTs in other gastrointestinal sites or for nonspecific abdominal masses. If the tumor site is not documented, check documentation before assigning a code.
Coding tip
Confirm the anatomic site in the pathology or operative note before coding, because GIST codes are site-specific.