Skip to main content

C49.A5 ICD-10-CM Code: Gastrointestinal stromal tumor of rectum

Compare with another codeCheck this code on a claim

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

Coding at a Glance

Tabular directives
10 inclusion terms · 5 Excludes1 · 7 Excludes2
Risk adjustment
CMS-HCC V28: 1 category · CMS-HCC V22 category 10 · RxHCC V08 category 20

Billable · FY2027A valid, specific ICD-10-CM code, reportable for dates of service in FY2027.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too; the Instructions section marks which is which.

Excludes1Never report with this code

+1 more in Instructions

Excludes2Not included here; may be reported together
  • Kaposi's sarcoma of soft tissue (C46.1)
  • malignant neoplasm of heart (C38.0)
  • malignant neoplasm of peripheral nerves and autonomic nervous system (C47.-)
  • malignant neoplasm of peritoneum (C48.2)

+3 more in Instructions

IncludesWhat this code covers
  • malignant neoplasm of blood vessel
  • malignant neoplasm of bursa
  • malignant neoplasm of cartilage
  • malignant neoplasm of fascia

+6 more in Instructions

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v44, Appendix B.

  • MS-DRG 374 — DIGESTIVE MALIGNANCY WITH MCC (MDC 06)
  • MS-DRG 375 — DIGESTIVE MALIGNANCY WITH CC (MDC 06)
  • MS-DRG 376 — DIGESTIVE MALIGNANCY WITHOUT CC/MCC (MDC 06)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Risk Adjustment (CMS-HCC)

Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.

  • HCC 23 — Prostate, Breast, and Other Cancers and Tumors

Other models: CMS-HCC V22 HCC 10 · RxHCC V08 HCC 20

Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for C49.A5 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on C49.A5 itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • malignant neoplasm of blood vessel
  • malignant neoplasm of bursa
  • malignant neoplasm of cartilage
  • malignant neoplasm of fascia
  • malignant neoplasm of fat
  • malignant neoplasm of ligament, except uterine
  • malignant neoplasm of lymphatic vessel
  • malignant neoplasm of muscle
  • malignant neoplasm of synovia
  • malignant neoplasm of tendon (sheath)

Source: inherited from C49

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from C49

Excludes2 — Not Included Here

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

Source: inherited from C49

Coder workflow for C49.A5

MedCoder structured workflow — derived from this code’s own official record

Before you code C49.A5

  1. Confirm the documented site and behavior (this code’s block classifies malignant neoplasms), whether the site is primary or secondary, and whether the malignancy is current or a personal history: a previously excised malignancy with no further treatment and no evidence of disease is history, not current disease. Verify the site against the Table of Neoplasms. Neoplasm chapter guidelines (Guidelines I.C.2.a, I.C.2.d, I.C.2.m).

    See the Table of Neoplasms entries · Guide: Active cancer vs history of cancer →

  2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with C49.A5. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support a condition named in C49.A5’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewC32.3, C30.0, C50

Consider C49.A5. Then confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Anatomical site
At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.
Behavior and current-versus-history status
Malignant, in situ, benign or uncertain; primary or secondary; current disease or personal history (Guidelines I.C.2.m).

Official instructions as workflow

  • Excludes1 — check before selecting C49.A5(5 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with C49.A5: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareC32.3, C30.0, C50

    See the official tabular notes · Guidelines I.A.12.a

  • Excludes2 — not part of C49.A5(7 notes)

    Coding workflow: The conditions named in this note are not included in C49.A5. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareC46.1, C38.0, C47, C48.2, C48.0, C57.3

    See the official tabular notes · Guidelines I.A.12.b

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Both the condition C49.A5 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewC32.3, C30.0, C50

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse C49.A5 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of C49.A5 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • C40— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of articular moves the case to C40; the two are not reported together unless documented as unrelated.

    Full comparison: C49.A5 vs C40 →

  • C41— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of articular moves the case to C41; the two are not reported together unless documented as unrelated.

    Full comparison: C49.A5 vs C41 →

  • C32.3— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of larynx moves the case to C32.3; the two are not reported together unless documented as unrelated.

    Full comparison: C49.A5 vs C32.3 →

  • C30.0— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of nose moves the case to C30.0; the two are not reported together unless documented as unrelated.

    Full comparison: C49.A5 vs C30.0 →

  • C50— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of malignant neoplasm of connective tissue of breast moves the case to C50; the two are not reported together unless documented as unrelated.

    Full comparison: C49.A5 vs C50 →

  • C49.A0— Specificity relationship (Review)

    Overlapping diagnoses in the same category.

    Overlapping codes in the same category — the documentation decides which is the more specific fit.

    What moves you there: A record that documents no more than “Gastrointestinal stromal tumor, unspecified site” takes C49.A0; specificity in the record moves it back here.

    Full comparison: C49.A5 vs C49.A0 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Gastrointestinal stromal tumor of rectum is a billable ICD-10-CM diagnosis code (C49.A5).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

  • CC as a secondary diagnosis (FY2027). Can raise the stay's MS-DRG severity tier.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name C49.A5 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 3 Excludes1 notes: C40 — Malignant neoplasm of bone and articular cartilage of limbs (via C49.-), C40-C41 — Malignant neoplasms of bone and articular cartilage (C40-C41) (via C49.-), C41 — Malignant neoplasm of bone and articular cartilage of other and unspecified sites (via C49.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 13 Excludes2 notes: C15 — Malignant neoplasm of esophagus (via C49.A.-), C15-C26 — Malignant neoplasms of digestive organs (C15-C26) (via C49.A.-), C16 — Malignant neoplasm of stomach (via C49.A.-), C17 — Malignant neoplasm of small intestine (via C49.A.-), C18 — Malignant neoplasm of colon (via C49.A.-), C19 — Malignant neoplasm of rectosigmoid junction (via C49.A.-), C20 — Malignant neoplasm of rectum (via C49.A.-), C21 — Malignant neoplasm of anus and anal canal (via C49.A.-), C22 — Malignant neoplasm of liver and intrahepatic bile ducts (via C49.A.-), C23 — Malignant neoplasm of gallbladder (via C49.A.-), C24 — Malignant neoplasm of other and unspecified parts of biliary tract (via C49.A.-), C25 — Malignant neoplasm of pancreas (via C49.A.-), C26 — Malignant neoplasm of other and ill-defined digestive organs (via C49.A.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 1 Code First instruction: M63 — Disorders of muscle in diseases classified elsewhere (via C49.-).

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 2 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 3 MS-DRGs: DRG 374 (MDC 06), DRG 375 (MDC 06), DRG 376 (MDC 06).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):NEO015 — Gastrointestinal cancers - colorectal (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

Z51.0 — Encounter for antineoplastic radiation therapy

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Prostate, Breast, and Other Cancers and Tumors) for risk-adjusted payment.

C43.72 — Malignant melanoma of left lower limb, including hip, C43.8 — Malignant melanoma of overlapping sites of skin, C43.9 — Malignant melanoma of skin, unspecified, C47.4 — Malignant neoplasm of peripheral nerves of abdomen, C49.4 — Malignant neoplasm of connective and soft tissue of abdomen, C49.A0 — Gastrointestinal stromal tumor, unspecified site, C49.A1 — Gastrointestinal stromal tumor of esophagus, C49.A2 — Gastrointestinal stromal tumor of stomach, C49.A3 — Gastrointestinal stromal tumor of small intestine, C49.A4 — Gastrointestinal stromal tumor of large intestine, C49.A9 — Gastrointestinal stromal tumor of other sites, C50.011 — Malignant neoplasm of nipple and areola, right female breast, C50.012 — Malignant neoplasm of nipple and areola, left female breast, C50.019 — Malignant neoplasm of nipple and areola, unspecified female breast, C50.021 — Malignant neoplasm of nipple and areola, right male breast, C50.022 — Malignant neoplasm of nipple and areola, left male breast, C50.029 — Malignant neoplasm of nipple and areola, unspecified male breast, C50.111 — Malignant neoplasm of central portion of right female breast, C50.112 — Malignant neoplasm of central portion of left female breast, C50.119 — Malignant neoplasm of central portion of unspecified female breast, +213 more

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic, Cancer Metastatic to Bone, Other and Unspecified Metastatic Cancer; Acute Leukemia Except Myeloid, Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers, Lung and Other Severe Cancers, Lymphoma and Other Cancers, Bladder, Colorectal, and Other Cancers

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Gastrointestinal cancers - colorectal).

C18.0 — Malignant neoplasm of cecum, C18.1 — Malignant neoplasm of appendix, C18.2 — Malignant neoplasm of ascending colon, C18.3 — Malignant neoplasm of hepatic flexure, C18.4 — Malignant neoplasm of transverse colon, C18.5 — Malignant neoplasm of splenic flexure, C18.6 — Malignant neoplasm of descending colon, C18.7 — Malignant neoplasm of sigmoid colon, C18.8 — Malignant neoplasm of overlapping sites of colon, C18.9 — Malignant neoplasm of colon, unspecified, C19 — Malignant neoplasm of rectosigmoid junction, C20 — Malignant neoplasm of rectum, C26.0 — Malignant neoplasm of intestinal tract, part unspecified, C49.A4 — Gastrointestinal stromal tumor of large intestine, D01.0 — Carcinoma in situ of colon, D01.1 — Carcinoma in situ of rectosigmoid junction, D01.2 — Carcinoma in situ of rectum, D01.40 — Carcinoma in situ of unspecified part of intestine

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Tumor”; these codes share that main term but sit in a different category of the Tabular List.

A52.17 — General paresis (syphilitic, brain), C18.1 — Malignant neoplasm of appendix (mucocarcinoid, unspecified site), C22.4 — Other sarcomas of liver (mesodermal, mixed, liver), C22.7 — Other specified carcinomas of liver (embryonal, liver), C24.0 — Malignant neoplasm of extrahepatic bile duct (Klatskin's), C25.4 — Malignant neoplasm of endocrine pancreas (G cell, malignant, pancreas), C30.0 — Malignant neoplasm of nasal cavity (neurogenic olfactory), C41.0 — Malignant neoplasm of bones of skull and face (odontogenic, malignant, upper jaw), C41.1 — Malignant neoplasm of mandible (odontogenic, malignant), C54.9 — Malignant neoplasm of corpus uteri, unspecified (Müllerian, mixed, unspecified site), C56 — Malignant neoplasm of ovary (Brenner, malignant), C56.9 — Malignant neoplasm of unspecified ovary (yolk sac, unspecified site, female), C62.90 — Malignant neoplasm of unspecified testis, unspecified whether descended or undescended (yolk sac, unspecified site, male), C64 — Malignant neoplasm of kidney, except renal pelvis (Wilms'), C71.9 — Malignant neoplasm of brain, unspecified (neuroectodermal, primitive, unspecified site), C73 — Malignant neoplasm of thyroid gland (Hurthle cell, malignant), C74.0 — Malignant neoplasm of cortex of adrenal gland (adrenal, cortical, malignant), C75.4 — Malignant neoplasm of carotid body (carotid body, malignant), C75.5 — Malignant neoplasm of aortic body and other paraganglia (aortic body, malignant), C79.6 — Secondary malignant neoplasm of ovary (Krukenberg's), +90 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Gamma-glutamyl Transferase (GGT) Test, Iron Panel

Contextual Map

Every relationship of C49.A5 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run C49.A5 with these 12 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Referenced by Excludes2 notes (13)

Referenced by Code First instructions

Clinical classification (CCSR)

Risk adjustment (CMS-HCC)

  • HCC 23 — Prostate, Breast, and Other Cancers and Tumors [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

  • CC — Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (CC).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2027
  • DRG 374 — DIGESTIVE MALIGNANCY WITH MCC[MS-DRG]: “DIGESTIVE MALIGNANCY WITH MCC (MDC 06)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
  • DRG 375 — DIGESTIVE MALIGNANCY WITH CC[MS-DRG]: “DIGESTIVE MALIGNANCY WITH CC (MDC 06)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
  • DRG 376 — DIGESTIVE MALIGNANCY WITHOUT CC/MCC[MS-DRG]: “DIGESTIVE MALIGNANCY WITHOUT CC/MCC (MDC 06)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027

MDC crossing

  • MDC 06 — Diseases and Disorders of the Digestive System[MDC crossing]: “Diseases and Disorders of the Digestive System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 5,748 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Index entries

  • Tumor, stromal, gastrointestinal, malignant, rectum[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Tumor, stromal, gastrointestinal, rectum[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027

Nearest codes (23)

Change history

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Indexed Clinical Terms (2)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44 Release, file and checksum · Publisher’s page
Risk adjustment Official source data
2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "C49.A5 — Gastrointestinal stromal tumor of rectum." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/c49.a5-gastrointestinal-stromal-tumor-of-rectum

Change history

  • FY2017 — October 1, 2016
    Added to the code set
    Gastrointestinal stromal tumor of rectum
    FY2017 changes

Nearest Codes in This Family

Official ICD-10-CM classifications closest to C49.A5 in its code family, with their registry titles.

View all codes in the C49 family