ICD-10 Code C18.3 – Malignant neoplasm of hepatic flexure (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C18.3 – Malignant neoplasm of hepatic flexure
What it is
C18.3 identifies a malignant tumor arising in the hepatic flexure, the bend of the colon near the liver. Use this code when documentation specifies cancer at this exact colonic site.
Clinical signs
Clinical features vary; refer to documentation. Patients may present with abdominal pain, change in bowel habits, anemia, weight loss, or signs of bowel obstruction, but the diagnosis must be site-specific.
When to use this code
Use C18.3 when the provider documents primary colon cancer at the hepatic flexure, including pathology, imaging, or operative findings that localize the tumor there. If the record only says “colon cancer” or another colon site, you should not default to this code. Check documentation when the exact location is unclear.
Do not use for
Do not use this code for benign polyps, carcinoma in situ, or malignancies documented in another part of the colon. If the site is unspecified or conflicting, code only what the record supports.
Coding tip
Look for the exact anatomic term “hepatic flexure” in the final pathology or provider assessment before assigning C18.3.