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ICD-10-CM 2027 diagnosis code

C26.0Malignant neoplasm of intestinal tract, part unspecified

✓ Billable / specific

C26.0 is a valid, billable ICD-10-CM code for malignant neoplasm of intestinal tract, part unspecified. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About C26.0

C26.0 is the ICD-10-CM diagnosis code for malignant neoplasm of intestinal tract, part unspecified. It belongs to category C26 (malignant neoplasm of other and ill-defined digestive organs), block C15-C26 (malignant neoplasms of digestive organs) and chapter 2 (neoplasms). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within C26, choose C26.0 (intestinal tract, part unspecified) only when documentation doesn't support a more specific option: spleen (C26.1) and ill-defined sites within the digestive system (C26.9).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 374 (Digestive Malignancy with MCC, relative weight 2.1109), DRG 375 (Digestive Malignancy with CC, relative weight 1.1838) and DRG 376 (Digestive Malignancy without CC/MCC, relative weight 0.8929), in MDC 06 (Diseases and Disorders of the Digestive System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 159.0 (malignant neoplasm of intestinal tract, part unspecified).

Coding notes

Applicable toConditions and synonyms classified to this code
  • Malignant neoplasm of intestine NOS

Notes that apply from higher levels

Instructions written at a parent level also apply to C26.0.

› From C26 Malignant neoplasm of other and ill-defined digestive organs
Excludes1
  • malignant neoplasm of peritoneum and retroperitoneum (C48.-)

Broader instructions also apply from C15-C26 Malignant neoplasms of digestive organs and Chapter 2: Neoplasms.

Table of Drugs & Neoplasms entries

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

ICD-9-CM equivalent

Converter →
  • 159.0Malignant neoplasm of intestinal tract, part unspecifiedexact

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about C26.0

Is C26.0 billable?

Yes. C26.0 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can C26.0 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict C26.0 as a principal diagnosis.

Is C26.0 a CC or MCC?

No. C26.0 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does C26.0 group to?

C26.0 is used in the MS-DRG v44.0 logic for MS-DRG 374 (Digestive Malignancy with MCC), MS-DRG 375 (Digestive Malignancy with CC) and MS-DRG 376 (Digestive Malignancy without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for C26.0?

The CMS General Equivalence Mappings map C26.0 to ICD-9-CM 159.0.