ICD-10 Code D19.1 – Benign neoplasm of mesothelial tissue of peritoneum (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D19.1 – Benign neoplasm of mesothelial tissue of peritoneum
What it is
D19.1 identifies a noncancerous growth arising from mesothelial tissue in the peritoneum, the lining of the abdominal cavity. Use it when documentation clearly states a benign mesothelial neoplasm at this site.
Clinical signs
Clinical features vary; refer to documentation. These lesions may be incidental or associated with nonspecific abdominal findings, and diagnosis is usually based on imaging, pathology, or operative findings.
When to use this code
Use D19.1 when the provider documents a benign neoplasm of peritoneal mesothelium, including pathology-confirmed benign mesothelial tumor of the peritoneum. Code it when the record specifies the site and benign nature. If the report is unclear, check documentation before assigning the code.
Do not use for
Do not use this code for malignant mesothelioma, peritoneal carcinomatosis, or other non-mesothelial abdominal tumors. If the lesion is described only as a mass or cyst without benign mesothelial confirmation, check documentation.
Coding tip
Confirm both the benign behavior and the peritoneal mesothelial origin in the record before coding D19.1.