2026 ICD-10-CM Diagnosis Code D37.5Neoplasm of uncertain behavior of rectum
ICD-10-CM Codes›C00–D49›D37-D48›D37
- Billable — Valid for Submission
- Not Chronic
D37.5 is a billable ICD-10-CM diagnosis code for neoplasm of uncertain behavior of rectum. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 374 through 376. Coders also document this condition as neoplasm of uncertain behavior of colon. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Neoplasms of unspecified nature or uncertain behavior.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Neoplasm of uncertain behavior of colon
- Neoplasm of uncertain behavior of rectosigmoid junction
- Neoplasm of uncertain behavior of rectum
- Neoplasm of uncertain behavior of sigmoid colon
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Neoplasm of uncertain behavior of rectosigmoid junction
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Table of NeoplasmsClinical
Anatomical sites in the Table of Neoplasms that reference this code family.
| Site | Malig. Primary | Malig. Secondary | Ca in situ | Benign | Uncertain | Unspec. |
|---|---|---|---|---|---|---|
| colon [See Also: Neoplasm, intestine, large] › with rectum | C19 | C78.5 | D01.1 | D12.7 | D37.5 | D49.0 |
| intestine, intestinal › large › colon › and rectum | C19 | C78.5 | D01.1 | D12.7 | D37.5 | D49.0 |
| junction › pelvirectal | C19 | C78.5 | D01.1 | D12.7 | D37.5 | D49.0 |
| junction › rectosigmoid | C19 | C78.5 | D01.1 | D12.7 | D37.5 | D49.0 |
| pelvirectal junction | C19 | C78.5 | D01.1 | D12.7 | D37.5 | D49.0 |
| rectosigmoid (junction) | C19 | C78.5 | D01.1 | D12.7 | D37.5 | D49.0 |
| rectum (ampulla) | C20 | C78.5 | D01.2 | D12.8 | D37.5 | D49.0 |
| rectum (ampulla) › and colon | C19 | C78.5 | D01.1 | D12.7 | D37.5 | D49.0 |
Patient EducationClinical
Rectal Disorders
The rectum is the lower part of your large intestine where your body stores stool. Problems with the rectum are common. They include hemorrhoids, abscesses, incontinence and cancer.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert D37.5 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About D37.5Overview
Is D37.5 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report neoplasm of uncertain behavior of rectum on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does D37.5 group to?
When neoplasm of uncertain behavior of rectum is the principal diagnosis on an inpatient stay, it groups to MS-DRG 374, 375, 376, with relative weights from 0.9243 to 2.1387 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of D37.5?
Under the General Equivalence Mappings, neoplasm of uncertain behavior of rectum converts to ICD-9-CM 235.2 (unc behav neo intestine). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
