C7A.020 Malignant carcinoid tumor of the appendix

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applies from C7A Malignant neuroendocrine tumors

Excludes2 (not included here)

• malignant pancreatic islet cell tumors (C25.4)
• Merkel cell carcinoma (C4A.-)

Use additional code

• code to identify any associated endocrine syndrome, such as:
• carcinoid syndrome (E34.00)

Code also

• any associated multiple endocrine neoplasia [MEN] syndromes (E31.2-)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 21 — Lymphoma and Other Cancers
• CMS-HCC V22: HCC 12 — Breast, Prostate, and Other Cancers and Tumors
• RxHCC V08: HCC 22 — Prostate, Breast, Bladder, and Other Cancers and Tumors
• ESRD V24: HCC 12

MS-DRG index

Defines the logic of DRG(s) 374-376 in MDC 06.

Approximate ICD-9-CM (GEMs)

• 209.11 Malignant carcinoid tumor of the appendix

Code annotations containing back-references to C7A.020

Back-references to C7A.02

• Type 1 Excludes: C18 Malignant neoplasm of colon ("malignant carcinoid tumors of the colon (C7A.02-)")
• Type 1 Excludes: C19 Malignant neoplasm of rectosigmoid junction ("malignant carcinoid tumors of the colon (C7A.02-)")
• Type 2 Excludes: C21 Malignant neoplasm of anus and anal canal ("malignant carcinoid tumors of the colon (C7A.02-)")

Back-references to C7A.0

• Type 1 Excludes: C75 Malignant neoplasm of other endocrine glands and related structures ("malignant carcinoid tumors (C7A.0-)")

Back-references to C7A

• Type 1 Excludes: C75 Malignant neoplasm of other endocrine glands and related structures ("malignant neuroendocrine tumors (C7A.-)")
• Code Also: E34.0 Carcinoid syndrome ("primary neuroendocrine tumors (C7A.-)")

Diagnosis Index entries for C7A.020

• Tumor › carcinoid › malignant › appendix

Nearby codes

• C7A.010 Malignant carcinoid tumor of the duodenum
• C7A.011 Malignant carcinoid tumor of the jejunum
• C7A.012 Malignant carcinoid tumor of the ileum
• C7A.019 Malignant carcinoid tumor of the small intestine, unspecified portion
• C7A.02 Malignant carcinoid tumors of the appendix, large intestine, and rectum
• C7A.020 Malignant carcinoid tumor of the appendix (this code)
• C7A.021 Malignant carcinoid tumor of the cecum
• C7A.022 Malignant carcinoid tumor of the ascending colon
• C7A.023 Malignant carcinoid tumor of the transverse colon
• C7A.024 Malignant carcinoid tumor of the descending colon
• C7A.025 Malignant carcinoid tumor of the sigmoid colon