C18.0
BillableMalignant neoplasm of cecum
HCC Category Mapping
V28HCC 22 — Colorectal, Bladder, and Other Cancers
0.000V24HCC 11 — Colorectal, Bladder, and Other Cancers
0.306ESRDHCC 11 — Colorectal, Bladder, and Other Cancers
0.000What This Code Means
Cancer that starts in the cecum, which is the pouch-like beginning of the large intestine where the small intestine connects.
Coding Tips
- •Cecal cancers often present late; document stage and histological type for complete coding
- •Distinguish from ascending colon cancer; the cecum is the first part of the colon
Clinical Significance
Malignant neoplasm of the cecum is one of the most common colorectal cancer locations, as the cecum is where the small intestine connects to the large intestine. Cecal cancers are classified as right-sided colon cancers, which have distinct molecular features and clinical behavior compared to left-sided cancers. These tumors often present with iron deficiency anemia and occult blood loss rather than overt obstruction, leading to later-stage diagnosis.
Documentation Requirements
- ✓Documentation confirming cecum as the primary tumor location
- ✓Histological type and grade (adenocarcinoma is most common)
- ✓Stage of disease including depth of invasion and lymph node status
- ✓Microsatellite instability or mismatch repair status if tested
- ✓Colonoscopy or surgical confirmation of location
Commonly Confused Codes
C18.2 — Ascending colon: the cecum is the initial pouch; the ascending colon begins above the ileocecal valve and runs superiorlyC17.2 — Ileum: the terminal ileum connects to the cecum; ensure the primary tumor is in the cecum, not the ileumC18.1 — Appendix: the appendix arises from the cecum; appendiceal tumors have a separate codeC18.9 — Colon, unspecified: use C18.0 when cecum is documented