ICD-10 Code C26 – Malignant neoplasm of other and ill-defined digestive organs (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C26 – Malignant neoplasm of other and ill-defined digestive organs
What it is
C26 identifies a malignant tumor arising in digestive organs that are not classified more specifically elsewhere. Use it when the record names an ill-defined or other digestive site and no more exact code is available.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include nonspecific abdominal pain, weight loss, or evidence of a mass, but the exact site and pathology should be confirmed in the medical record.
When to use this code
Use C26 when the provider documents a primary malignancy of an unspecified, other, or ill-defined digestive organ and no more specific anatomic code applies. It is also appropriate when pathology confirms malignancy but the exact digestive site is not clearly documented. Check documentation if the site could be coded elsewhere.
Do not use for
Do not use C26 if the cancer is documented in a specific digestive organ with its own code, such as stomach, colon, or pancreas. Also avoid it for benign tumors, metastatic disease, or uncertain behavior neoplasms.
Coding tip
Code the most specific digestive site stated in the record; use C26 only when the documentation remains vague or grouped as “other” or “ill-defined.”