2024 ICD-10-CM Diagnosis Code C21.1

Malignant neoplasm of anal canal

ICD-10-CM Code:
C21.1
ICD-10 Code for:
Malignant neoplasm of anal canal
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Chronic
Code Navigator:

Code Classification

  • Neoplasms
    (C00–D49)
    • Malignant neoplasms of digestive organs
      (C15-C26)
      • Malignant neoplasm of anus and anal canal
        (C21)

C21.1 is a billable diagnosis code used to specify a medical diagnosis of malignant neoplasm of anal canal. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

The following anatomical sites found in the Table of Neoplasms reference this diagnosis code given the correct histological behavior: Neoplasm, neoplastic anus, anal canal ; Neoplasm, neoplastic anus, anal sphincter ; Neoplasm, neoplastic canal ; Neoplasm, neoplastic canal anal ; Neoplasm, neoplastic hemorrhoidal zone ; Neoplasm, neoplastic sphincter ; Neoplasm, neoplastic sphincter anal ; etc

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Adenocarcinoma of anal canal
  • Adenocarcinoma of anus
  • Anorectal adenocarcinoma
  • Carcinoma of anal canal
  • Malignant melanoma of anus
  • Malignant melanoma of perineum
  • Malignant tumor of anal canal
  • Paget disease of anal canal
  • Perianal Paget's disease
  • Perianal Paget's disease
  • Primary carcinoma of anal canal
  • Primary malignant melanoma of anal canal
  • Primary malignant melanoma of anus
  • Primary malignant neoplasm of anal canal
  • Primary malignant neoplasm of perianal skin
  • Primary Paget disease of anal canal
  • Primary perianal Paget disease
  • Primary squamous cell carcinoma of anal canal
  • Primary squamous cell carcinoma of anus

Clinical Classification

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Inclusion Terms

Inclusion Terms
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.
  • Malignant neoplasm of anal sphincter

Convert C21.1 to ICD-9-CM

  • ICD-9-CM Code: 154.2 - Malig neopl anal canal

Table of Neoplasms

This code is referenced in the table of neoplasms by anatomical site. For each site there are six possible code numbers according to whether the neoplasm in question is malignant, benign, in situ, of uncertain behavior, or of unspecified nature. The description of the neoplasm will often indicate which of the six columns is appropriate.

Where such descriptors are not present, the remainder of the Index should be consulted where guidance is given to the appropriate column for each morphological (histological) variety listed. However, the guidance in the Index can be overridden if one of the descriptors mentioned above is present.

Neoplasm, neoplastic Malignant
Primary
Malignant
Secondary
CaInSitu Benign Uncertain
Behavior
Unspecified
Behavior
»Neoplasm, neoplastic
  »anus, anal
    »canal
C21.1C78.5D01.3D12.9D37.8D49.0
»Neoplasm, neoplastic
  »anus, anal
    »sphincter
C21.1C78.5D01.3D12.9D37.8D49.0
»Neoplasm, neoplastic
  »canal
C21.1C78.5D01.3D12.9D37.8D49.0
»Neoplasm, neoplastic
  »canal
    »anal
C21.1C78.5D01.3D12.9D37.8D49.0
»Neoplasm, neoplastic
  »hemorrhoidal zone
C21.1C78.5D01.3D12.9D37.8D49.0
»Neoplasm, neoplastic
  »sphincter
C21.1C78.5D01.3D12.9D37.8D49.0
»Neoplasm, neoplastic
  »sphincter
    »anal
C21.1C78.5D01.3D12.9D37.8D49.0

Patient Education


Anal Cancer

The anus is where stool leaves your body when you go to the bathroom. It is made up of your outer layers of skin and the end of your large intestine. Anal cancer is a disease in which cancer cells form in the tissues of the anus.

Anal cancer is rare. It is more common in smokers and people over 50. You are also at higher risk if you have HPV, have anal sex, or have many sexual partners.

Symptoms include bleeding, pain, or lumps in the anal area. Anal itching and discharge can also be signs of anal cancer.

Doctors use tests that examine the anus to diagnose anal cancer. They include a physical exam, endoscopy, ultrasound, and biopsy.

Treatments include radiation therapy, chemotherapy, and surgery.

NIH: National Cancer Institute


[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.