C45.1
BillableMesothelioma of peritoneum
HCC Category Mapping
V28HCC 19 — Lymphoma and Other Cancers
0.105V24HCC 9 — Lung and Other Severe Cancers
0.973ESRDHCC 9 — Lung and Other Severe Cancers
0.000RxHCCHCC 22 — Cancer, Other Specified Sites
0.000What This Code Means
A rare cancer that develops in the membrane lining the abdominal cavity (peritoneum), typically associated with asbestos exposure.
Coding Tips
- •Peritoneal mesothelioma often presents later than pleural mesothelioma; document stage and extent of disease when available
- •Distinguish from other abdominal malignancies by confirming mesothelial origin in pathology documentation
Clinical Significance
Mesothelioma of the peritoneum is a rare but aggressive cancer of the abdominal lining, also associated with asbestos exposure although the association is weaker than with pleural mesothelioma. Peritoneal mesothelioma has a slightly better prognosis than pleural mesothelioma, especially when treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.
Documentation Requirements
- ✓Histologic confirmation of peritoneal mesothelioma (epithelioid subtype has better prognosis)
- ✓Asbestos exposure history if present
- ✓Extent of peritoneal involvement (peritoneal cancer index scoring)
- ✓Whether eligible for cytoreductive surgery with hyperthermic intraperitoneal chemotherapy
- ✓Distinction from pseudomyxoma peritonei or peritoneal carcinomatosis from other primaries
- ✓Treatment plan and disease status
Excludes 1 — Do NOT code together
- other malignant neoplasm of soft tissue of peritoneum (C48.-)
Commonly Confused Codes
C45.0 — Mesothelioma of pleura; different serosal surface (chest vs. abdomen)C48.1 — Malignant neoplasm of specified parts of peritoneum; for non-mesothelioma peritoneal cancersC78.6 — Secondary malignant neoplasm of retroperitoneum and peritoneum; for peritoneal carcinomatosis from ovarian, colon, or gastric cancerC45.2 — Mesothelioma of pericardium; different serosal surface