ICD-10 Code C16.3 – Malignant neoplasm of pyloric antrum (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C16.3 – Malignant neoplasm of pyloric antrum
What it is
C16.3 identifies a malignant tumor arising in the pyloric antrum, the lower stomach region near the pylorus. Use it when documentation specifies cancer in this exact gastric subsite.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings in gastric cancer include weight loss, epigastric discomfort, early satiety, nausea, vomiting, or evidence of gastric outlet obstruction.
When to use this code
Use C16.3 when the provider documents primary cancer of the pyloric antrum, including pathology, endoscopy, or imaging that localizes the malignancy to that stomach segment. Assign it for confirmed malignant neoplasm of this site, not for vague “stomach cancer” unless the antrum is named.
Do not use for
Do not use this code for benign gastric lesions, dysplasia, or malignant disease documented in another stomach subsite. Check documentation if the record only says “gastric cancer” without anatomic detail.
Coding tip
Code the documented anatomic site exactly; if the pyloric antrum is not specified, query for clarification before assigning C16.3.