C48.8
BillableMalignant neoplasm of overlapping sites of retroperitoneum and peritoneum
HCC Category Mapping
V28HCC 20 — Lung and Other Severe Cancers
0.000V24HCC 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 malignant (cancerous) tumor that involves multiple overlapping areas of both the retroperitoneum (space behind the abdominal cavity) and the peritoneum (abdominal lining).
Coding Tips
- •Use this code specifically when the cancer involves both retroperitoneal and peritoneal sites; do not use for tumors limited to one area
- •Document the extent of involvement in both anatomical regions to support medical necessity
Clinical Significance
Malignant neoplasm of overlapping sites of retroperitoneum and peritoneum indicates a tumor that involves both retroperitoneal and peritoneal spaces simultaneously. This reflects extensive disease requiring complex surgical planning and typically indicates advanced-stage malignancy with significant treatment implications.
Documentation Requirements
- ✓Pathology confirming malignancy involving both retroperitoneal and peritoneal spaces
- ✓Imaging documenting the overlapping nature of the tumor across both compartments
- ✓Explanation of why a single-site code (C48.0 or C48.1) is insufficient
- ✓Surgical findings describing the extent of cross-compartment involvement
- ✓Treatment plan addressing the multi-compartment disease
Commonly Confused Codes
C48.0 (Retroperitoneum) — use when tumor is confined to the retroperitoneumC48.1 (Specified parts of peritoneum) — use when tumor is confined to the peritoneumC48.2 (Peritoneum, unspecified) — for unknown site within peritoneum, not overlapping compartmentsC78.6 (Secondary malignant neoplasm of retroperitoneum and peritoneum) — metastatic disease, not primary
Code Hierarchy
└C48Malignant neoplasm of retroperitoneum and peritoneum└C48.8Malignant neoplasm of overlapping sites of retroperitoneum and peritoneum
└C48.8Malignant neoplasm of overlapping sites of retroperitoneum and peritoneum