ICD-10/C26.9

C26.9 ICD 2026 Code: Malignant neoplasm of ill-defined sites within the digestive system

C26.9 is the authoritative medical code for Malignant neoplasm of ill-defined sites within the digestive system. This classification is used in medical billing and clinical recording to specify the clinical criteria for malignant neoplasm of ill-defined sites within the digestive system (ICD-10-CM C26.9), ensuring healthcare documentation aligns with 2026 federal coding standards.

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Official Registry Overview & Definition

Malignant neoplasm of ill-defined sites within the digestive system is a billable ICD-10-CM diagnosis code C26.9. Inclusion terms: Malignant neoplasm of alimentary canal or tract NOS; Malignant neoplasm of gastrointestinal tract NOS. Excludes1 (not coded here): malignant neoplasm of abdominal NOS C76.2; malignant neoplasm of intra-abdominal NOS C76.2; malignant neoplasm of peritoneum and retroperitoneum C48.-; Kaposi's sarcoma of gastrointestinal sites C46.4. Excludes2 (not included here): gastrointestinal stromal tumors C49.A-.

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for C26.9 in the official ICD-10-CM tabular list.

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Malignant neoplasm of alimentary canal or tract NOS
  • Malignant neoplasm of gastrointestinal tract NOS

Excludes1 — Not Coded Here

Conditions that can never be reported with this code; the two are mutually exclusive.

  • malignant neoplasm of abdominal NOS C76.2
  • malignant neoplasm of intra-abdominal NOS C76.2
  • malignant neoplasm of peritoneum and retroperitoneum C48.-
  • Kaposi's sarcoma of gastrointestinal sites C46.4

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

  • gastrointestinal stromal tumors C49.A-

Frequently Asked Questions (FAQ) & Clinical Guidance

What can't be coded together with C26.9?

Per official ICD-10-CM Excludes1 instructions, C26.9 must not be reported together with: malignant neoplasm of abdominal NOS (C76.2); malignant neoplasm of intra-abdominal NOS (C76.2); malignant neoplasm of peritoneum and retroperitoneum (C48.-); Kaposi's sarcoma of gastrointestinal sites (C46.4).

Can C26.9 be reported alongside related conditions?

Per official ICD-10-CM Excludes2 instructions, C26.9 and the following are not considered part of each other and may both be reported when both conditions are present: gastrointestinal stromal tumors (C49.A-).

What conditions are included under C26.9?

Malignant neoplasm of ill-defined sites within the digestive system includes: Malignant neoplasm of alimentary canal or tract NOS; Malignant neoplasm of gastrointestinal tract NOS.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to C26.9 in its code family, with their registry titles.

  • C26 — Malignant neoplasm of other and ill-defined digestive organs
  • C26.0 — Malignant neoplasm of intestinal tract, part unspecified
  • C26.1 — Malignant neoplasm of spleen

Neoplasm Table Sites (5)

Anatomical sites from the official ICD-10-CM Table of Neoplasms that map to this code, with the matching behavior column.

  • Neoplasm, neoplastic, alimentary canal or tract NEC — Malignant, Primary
  • Neoplasm, neoplastic, digestive organs, system, tube, or tract NEC — Malignant, Primary
  • Neoplasm, neoplastic, gastrocolic — Malignant, Primary
  • Neoplasm, neoplastic, gastrointestinal NEC (tract) — Malignant, Primary
  • Neoplasm, neoplastic, peritoneum, peritoneal (cavity), overlapping lesion, with digestive organs — Malignant, Primary