C7A.012 Malignant carcinoid tumor of the ileum

ICD-10-CM Code C7A.012: Malignant carcinoid tumor of the ileum

ICD-10-CM code C7A.012 identifies a malignant carcinoid tumor located in the ileum. This active diagnosis concept is a narrower term under small intestine carcinoid tumors. Clinical literature establishes that small intestinal carcinoid tumors are slow-growing neoplastic processes that may present incidentally or with carcinoid syndrome if metastasis occurs. 1 2

Plain-language overview

Code C7A.012 identifies a specific type of malignant neoplasm known as a carcinoid tumor that is located in the ileum, which is a section of the small intestine. 1

What this code represents

The diagnosis concept C7A.012 is an active terminology record classified as a neoplastic process, representing a narrower condition under the parent category of malignant carcinoid tumors of the small intestine. 1

Clinical context

Clinical literature indicates that the majority of small intestinal carcinoid tumors occur in the terminal ileum within one meter of the ileocecal valve and are frequently asymptomatic, slow-growing lesions. 2

If a primary small bowel carcinoid tumor reaches two centimeters, the risk of liver metastasis increases substantially, which may lead to carcinoid syndrome characterized by episodic flushing, watery diarrhea, and wheezing. 2

Coding details

Code C7A.012 provides specific anatomical documentation for an ileal carcinoid, distinguishing it from C7A.019, which denotes a malignant carcinoid tumor of the small intestine when the portion is unspecified. 5

Documentation considerations

Clinical literature divides small bowel carcinoid tumors into two groups, separating tumors of the duodenum and upper jejunum from tumors of the distal jejunum and ileum. 2

Coverage and utilization context

A payer policy indicates that the Chromogranin A tumor marker, billed under procedure code 86316, may be utilized to assist in the diagnosis and management of specific carcinoid tumors rather than being universally investigational. 4

What the sources add

While the terminology record defines the code hierarchy and neoplastic classification, the clinical reference provides operational context regarding the slow growth, metastatic risk, and anatomical prevalence of small bowel carcinoid tumors. 1 2

A phecode mapping resource groups multiple malignant carcinoid tumor diagnoses together, listing small intestine carcinoids alongside similar neoplasms of the colon, rectum, appendix, bronchus, and lung. 3

Sources

1. ICD-10-CM C7A.012 terminology record — National Cancer Institute Enterprise Vocabulary Services; accessed 2026-07-27.
2. Current Advance in Small Bowel Tumors — pmc.ncbi.nlm.nih.gov; accessed 2026-07-27.
3. Phecode 195.1 · ExPRSweb — csg.sph.umich.edu; accessed 2026-07-27.
4. Tumor Markers for Diagnosis and Management of Cancer — bluecrossma.org; accessed 2026-07-27.
5. How to Report Neuroendocrine Tumors using ICD-10 Codes — outsourcestrategies.com; accessed 2026-07-27.