2024 ICD-10-CM Diagnosis Code Z51.0

Encounter for antineoplastic radiation therapy

ICD-10-CM Code:
Z51.0
ICD-10 Code for:
Encounter for antineoplastic radiation therapy
Is Billable?
Yes - Valid for Submission
Code Navigator:

Code Classification

  • Factors influencing health status and contact with health services
    (Z00–Z99)
    • Encounters for other specific health care
      (Z40-Z53)
      • Encounter for other aftercare and medical care
        (Z51)

Z51.0 is a billable diagnosis code used to specify a medical diagnosis of encounter for antineoplastic radiation therapy. 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 code is exempt from present on admission (POA) reporting for inpatient admissions to general acute care hospitals.

Approximate Synonyms

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

  • Chemotherapy AND/OR radiation therapy prior to lymphadenectomy
  • Radiotherapy started

Clinical Classification

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Present on Admission (POA)

Z51.0 is exempt from POA reporting - The Present on Admission (POA) indicator is used for diagnosis codes included in claims involving inpatient admissions to general acute care hospitals. POA indicators must be reported to CMS on each claim to facilitate the grouping of diagnoses codes into the proper Diagnostic Related Groups (DRG). CMS publishes a listing of specific diagnosis codes that are exempt from the POA reporting requirement. Review other POA exempt codes here.

CMS POA Indicator Options and Definitions

POA IndicatorReason for CodeCMS will pay the CC/MCC DRG?
YDiagnosis was present at time of inpatient admission.YES
NDiagnosis was not present at time of inpatient admission.NO
UDocumentation insufficient to determine if the condition was present at the time of inpatient admission.NO
WClinically undetermined - unable to clinically determine whether the condition was present at the time of inpatient admission.YES
1Unreported/Not used - Exempt from POA reporting. NO

Convert Z51.0 to ICD-9-CM

  • ICD-9-CM Code: V58.0 - Radiotherapy encounter

Patient Education


Radiation Therapy

Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from spreading. About half of all cancer patients receive it. The radiation may be external, from special machines, or internal, from radioactive substances that a doctor places inside your body. The type of radiation therapy you receive depends on many factors, including:

  • The type of cancer
  • The size of the cancer
  • The cancer's location in the body
  • How close the cancer is to normal tissues that are sensitive to radiation
  • How far into the body the radiation needs to travel
  • Your general health and medical history
  • Whether you will have other types of cancer treatment
  • Other factors, such as your age and other medical conditions

Radiation therapy can damage normal cells as well as cancer cells. Treatment must be carefully planned to minimize side effects. Common side effects include skin changes and fatigue. Other side effects depend on the part of your body being treated.

Sometimes radiation is used with other treatments, like surgery or chemotherapy.

NIH: National Cancer Institute


[Learn More in MedlinePlus]

Radiation Therapy to Treat Cancer

Radiation therapy is a type of cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumors. Learn about the types of radiation, why side effects happen, which ones you might have, and more.
[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.