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D01.1 ICD-10-CM Code: Carcinoma in situ of rectosigmoid junction

Compare with another code for D01.1Check 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
4 inclusion terms · 1 Excludes1

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, and is marked with where it comes from.

Excludes1from D01Not reported with this code unless documented as unrelated
  • melanoma in situ (D03.-)
Includesfrom D00-D09What D00-D09 covers
  • Bowen's disease
  • erythroplasia
  • grade III intraepithelial neoplasia
  • Queyrat's erythroplasia

Where it sits Source: CMS/NCHS

Under:Chapter 2: NeoplasmsD00-D09 In situ neoplasmsD01 Carcinoma in situ of other and unspecified digestive organs

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.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for D01.1 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 D01.1 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.

  • Bowen's disease
  • erythroplasia
  • grade III intraepithelial neoplasia
  • Queyrat's erythroplasia

Source: inherited from D00-D09

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 D01

Coder workflow for D01.1

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

Before you code D01.1

  1. Confirm the documented site and behavior (this code’s block classifies in situ 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 D01.1. 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 D01.1’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.

    ReviewD03

Consider D01.1. 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 D01.1(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with D01.1: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareD03

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

Coding decision scenarios

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

Documentation: Both the condition D01.1 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).

ReviewD03

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 D01.1 with…

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

The codes most likely to be picked instead of D01.1 — 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.

  • D03— 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 melanoma in situ moves the case to D03; the two are not reported together unless documented as unrelated.

    Full comparison: D01.1 vs D03 →

  • D01.4— 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 “Carcinoma in situ of other and unspecified parts of intestine” takes D01.4; specificity in the record moves it back here.

    Full comparison: D01.1 vs D01.4 →

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

Carcinoma in situ of rectosigmoid junction is a billable ICD-10-CM diagnosis code (D01.1).

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

  • No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

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 D01.1 or its code family, from the CMS ICD-10-CM tabular instructional notes, the CMS Table of Neoplasms and the CMS Table of Neoplasms (site match derived from the code title). Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Excludes1 note: D01.0 — Carcinoma in situ of colon.

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

Referenced by 5 Same-site neoplasm codes: C19 — Malignant neoplasm of rectosigmoid junctionCompare D01.1 vs C19 →, C78.5 — Secondary malignant neoplasm of large intestine and rectumCompare D01.1 vs C78.5 →, D12.7 — Benign neoplasm of rectosigmoid junctionCompare D01.1 vs D12.7 →, D37.5 — Neoplasm of uncertain behavior of rectumCompare D01.1 vs D37.5 →, D49.0 — Neoplasm of unspecified behavior of digestive systemCompare D01.1 vs D49.0 →.

These codes represent related neoplasm behaviors affecting the same anatomic site.

Referenced by 12 Screening & history codes: Z12.11 — Encounter for screening for malignant neoplasm of colonCompare D01.1 vs Z12.11 →, Z12.12 — Encounter for screening for malignant neoplasm of rectumCompare D01.1 vs Z12.12 →, Z12.13 — Encounter for screening for malignant neoplasm of small intestineCompare D01.1 vs Z12.13 →, Z85.03 — Personal history of malignant neoplasm of large intestineCompare D01.1 vs Z85.03 →, Z85.030 — Personal history of malignant carcinoid tumor of large intestineCompare D01.1 vs Z85.030 →, Z85.038 — Personal history of other malignant neoplasm of large intestineCompare D01.1 vs Z85.038 →, Z85.04 — Personal history of malignant neoplasm of rectum, rectosigmoid junction, and anusCompare D01.1 vs Z85.04 →, Z85.040 — Personal history of malignant carcinoid tumor of rectumCompare D01.1 vs Z85.040 →, Z85.048 — Personal history of other malignant neoplasm of rectum, rectosigmoid junction, and anusCompare D01.1 vs Z85.048 →, Z85.06 — Personal history of malignant neoplasm of small intestineCompare D01.1 vs Z85.06 →, Z85.060 — Personal history of malignant carcinoid tumor of small intestineCompare D01.1 vs Z85.060 →, Z85.068 — Personal history of other malignant neoplasm of small intestineCompare D01.1 vs Z85.068 →.

These codes represent screening tests and history codes that refer to this active disease condition.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

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 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, C49.A5 — Gastrointestinal stromal tumor of rectum, D01.0 — Carcinoma in situ of colon, D01.2 — Carcinoma in situ of rectum, D01.40 — Carcinoma in situ of unspecified part of intestine

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.

CEA Test, Fecal Occult Blood Test (FOBT), Iron Panel

Contextual Map

Every relationship of D01.1 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 D01.1 with this related code in Claim Check

Hierarchy

Same site

Referenced by Excludes1 notes

Referenced by Same-site neoplasm codes

Referenced by Screening & history codes (12) MedCoder-derived

Clinical classification (CCSR)

MS-DRG Grouper

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

Neoplasm sites

  • Neoplasm, neoplastic, colon, with rectum — Neoplasm, neoplastic, colon, with rectum — Ca in situ [Neoplasm table]: “Neoplasm, neoplastic, colon, with rectum (Ca in situ)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, intestine, intestinal, large, colon, and rectum — Neoplasm, neoplastic, intestine, intestinal, large, colon, and rectum — Ca in situ [Neoplasm table]: “Neoplasm, neoplastic, intestine, intestinal, large, colon, and rectum (Ca in situ)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, junction, pelvirectal — Neoplasm, neoplastic, junction, pelvirectal — Ca in situ [Neoplasm table]: “Neoplasm, neoplastic, junction, pelvirectal (Ca in situ)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, junction, rectosigmoid — Neoplasm, neoplastic, junction, rectosigmoid — Ca in situ [Neoplasm table]: “Neoplasm, neoplastic, junction, rectosigmoid (Ca in situ)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, pelvirectal junction — Neoplasm, neoplastic, pelvirectal junction — Ca in situ [Neoplasm table]: “Neoplasm, neoplastic, pelvirectal junction (Ca in situ)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, rectosigmoid (junction) — Neoplasm, neoplastic, rectosigmoid (junction) — Ca in situ [Neoplasm table]: “Neoplasm, neoplastic, rectosigmoid (junction) (Ca in situ)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, rectum (ampulla), and colon — Neoplasm, neoplastic, rectum (ampulla), and colon — Ca in situ [Neoplasm table]: “Neoplasm, neoplastic, rectum (ampulla), and colon (Ca in situ)”— CMS Table of Neoplasms · icd10cm-fy2027

Nearest codes (10)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

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.

Neoplasm Table Sites (7)

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

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

  • Neoplasm, neoplastic, colon, with rectum — Ca in situ
  • Neoplasm, neoplastic, intestine, intestinal, large, colon, and rectum — Ca in situ
  • Neoplasm, neoplastic, junction, pelvirectal — Ca in situ
  • Neoplasm, neoplastic, junction, rectosigmoid — Ca in situ
  • Neoplasm, neoplastic, pelvirectal junction — Ca in situ
  • Neoplasm, neoplastic, rectosigmoid (junction) — Ca in situ
  • Neoplasm, neoplastic, rectum (ampulla), and colon — Ca in situ

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
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. "D01.1 — Carcinoma in situ of rectosigmoid junction." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/d01.1-carcinoma-in-situ-of-rectosigmoid-junction

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Carcinoma in situ of rectosigmoid junction

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to D01.1 in its code family, with their registry titles.

View all codes in the D01 family