Malignant neoplasm of specified parts of peritoneum

This code signifies a primary cancerous tumor originating in a specific, identified portion of the peritoneum, the membrane lining the abdominal cavity and covering abdominal organs. It indicates a localized malignancy rather than a widespread peritoneal carcinomatosis.

Apply this code when documentation clearly specifies a primary malignant neoplasm of a particular peritoneal site, such as the parietal peritoneum, visceral peritoneum, or omentum, without evidence of widespread dissemination. This is appropriate for biopsy-confirmed primary tumors of the peritoneum.

• Distinguish from secondary malignant neoplasm of the peritoneum (metastatic disease) which would be coded differently.
• Ensure the documentation specifies a primary site within the peritoneum, not just "peritoneal carcinomatosis."
• If the specific part of the peritoneum is not documented, consider querying the physician for clarification.