ICD10BillableValid for clinical use
ICD-10 Code C19: Malignant neoplasm of rectosigmoid junction
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Neoplasms (C00-D49).
When is it used?
- May be used when a clinician documents malignant neoplasm of rectosigmoid junction in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code can be used as a clinically usable diagnosis entry in standardized coding workflows.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
Code hierarchy
chapter
2Neoplasms (C00-D49)
block
C00-C96Malignant neoplasms
block
C00-C75Malignant neoplasms, stated or presumed to be primary (of specified sites), and certain specified histologies, except neuroendocrine, and of lymphoid, hematopoietic and related tissue
block
C15-C26Malignant neoplasms of digestive organs
currentC15-C26
Official coding notes
Inclusion terms
- Malignant neoplasm of colon with rectum
- Malignant neoplasm of rectosigmoid (colon)
Excludes1 (do not code together)
- malignant carcinoid tumors of the colon (C7A.02-)
Where you may see this code
You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.
Related specialists
OncologistGeneral Physician
Related codes
C15Malignant neoplasm of esophaguscategoryC16Malignant neoplasm of stomachcategoryC17Malignant neoplasm of small intestinecategoryC18Malignant neoplasm of coloncategoryC20Malignant neoplasm of rectumcodeC21Malignant neoplasm of anus and anal canalcategoryC22Malignant neoplasm of liver and intrahepatic bile ductscategoryC23Malignant neoplasm of gallbladdercodeC24Malignant neoplasm of other and unspecified parts of biliary tractcategoryC25Malignant neoplasm of pancreascategoryC26Malignant neoplasm of other and ill-defined digestive organscategory
Sibling codes
C15Malignant neoplasm of esophagusC16Malignant neoplasm of stomachC17Malignant neoplasm of small intestineC18Malignant neoplasm of colonC20Malignant neoplasm of rectumbillableC21Malignant neoplasm of anus and anal canalC22Malignant neoplasm of liver and intrahepatic bile ductsC23Malignant neoplasm of gallbladderbillableC24Malignant neoplasm of other and unspecified parts of biliary tractC25Malignant neoplasm of pancreasC26Malignant neoplasm of other and ill-defined digestive organs
Coverage-related procedures and services
CPT 81479high
UNLISTED MOLECULAR PATHOLOGY PROCEDURE
Source: CMS coverage guidance
CPT 81445high
SOLID ORGAN NEOPLASM, GENOMIC SEQUENCE ANALYSIS PANEL, 5-50 GENES, INTERROGATION FOR SEQUENCE VARIANTS AND COPY NUMBER VARIANTS OR REARRANGEMENTS, IF PERFORMED; DNA ANALYSIS OR COMBINED DNA AND RNA ANALYSIS
Source: CMS coverage guidance
CPT 44388high
COLONOSCOPY THROUGH STOMA; DIAGNOSTIC, INCLUDING COLLECTION OF SPECIMEN(S) BY BRUSHING OR WASHING, WHEN PERFORMED (SEPARATE PROCEDURE)
Source: CMS coverage guidance
CPT 44401high
COLONOSCOPY THROUGH STOMA; WITH ABLATION OF TUMOR(S), POLYP(S), OR OTHER LESION(S) (INCLUDES PRE-AND POST-DILATION AND GUIDE WIRE PASSAGE, WHEN PERFORMED)
Source: CMS coverage guidance
CPT 44389high
COLONOSCOPY THROUGH STOMA; WITH BIOPSY, SINGLE OR MULTIPLE
Source: CMS coverage guidance
CPT 44391high
COLONOSCOPY THROUGH STOMA; WITH CONTROL OF BLEEDING, ANY METHOD
Source: CMS coverage guidance
Mapped diagnoses and classifications
SNOMED_CT 425178004high
Adenocarcinoma of rectosigmoid junction
Source: SNOMED International ICD-10 map
SNOMED_CT 269544008high
Carcinoma of rectosigmoid junction
Source: SNOMED International ICD-10 map
SNOMED_CT 363414004high
Malignant neoplasm of rectosigmoid junction
Source: SNOMED International ICD-10 map
SNOMED_CT 737058005high
Microsatellite instability-high colorectal cancer
Source: SNOMED International ICD-10 map
SNOMED_CT 96281000119107high
Overlapping malignant neoplasm of colon and rectum
Source: SNOMED International ICD-10 map
SNOMED_CT 184881000119106high
Primary adenocarcinoma of rectosigmoid junction
Source: SNOMED International ICD-10 map
Coding guidelines
Compatibility
Legacy and official ICD code match exactly.
Legacy codes
C19
Common synonyms
Malignant neoplasm of rectosigmoid junction
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.