ICD10BillableValid for clinical use

ICD-10 Code Z51.11: Encounter for antineoplastic chemotherapy

Z51.11 is a billable ICD-10 diagnosis code used to classify Encounter for antineoplastic chemotherapy in medical records and claims. You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records. 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 Factors influencing health status and contact with health services (Z00-Z99).

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 Factors influencing health status and contact with health services (Z00-Z99).

When is it used?

  • May be used when a clinician documents encounter for antineoplastic chemotherapy 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
21Factors influencing health status and contact with health services (Z00-Z99)
block
Z40-Z53Encounters for other specific health care
category
Z51Encounter for other aftercare and medical care
category
Z51.1Encounter for antineoplastic chemotherapy and immunotherapy
currentZ51.1

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

General Physician

Coverage-related procedures and services

CPT 87507high
INFECTIOUS AGENT DETECTION BY NUCLEIC ACID (DNA OR RNA); GASTROINTESTINAL PATHOGEN (EG, CLOSTRIDIUM DIFFICILE, E. COLI, SALMONELLA, SHIGELLA, NOROVIRUS, GIARDIA), INCLUDES MULTIPLEX REVERSE TRANSCRIPTION, WHEN PERFORMED, AND MULTIPLEX AMPLIFIED PROBE TECHNIQUE, MULTIPLE TYPES OR SUBTYPES, 12-25 TARGETS
Source: CMS coverage guidance
CPT 87506high
INFECTIOUS AGENT DETECTION BY NUCLEIC ACID (DNA OR RNA); GASTROINTESTINAL PATHOGEN (EG, CLOSTRIDIUM DIFFICILE, E. COLI, SALMONELLA, SHIGELLA, NOROVIRUS, GIARDIA), INCLUDES MULTIPLEX REVERSE TRANSCRIPTION, WHEN PERFORMED, AND MULTIPLEX AMPLIFIED PROBE TECHNIQUE, MULTIPLE TYPES OR SUBTYPES, 6-11 TARGETS
Source: CMS coverage guidance
CPT 87801high
INFECTIOUS AGENT DETECTION BY NUCLEIC ACID (DNA OR RNA), MULTIPLE ORGANISMS; AMPLIFIED PROBE(S) TECHNIQUE
Source: CMS coverage guidance
CPT 87633high
INFECTIOUS AGENT DETECTION BY NUCLEIC ACID (DNA OR RNA); RESPIRATORY VIRUS (EG, ADENOVIRUS, INFLUENZA VIRUS, CORONAVIRUS, METAPNEUMOVIRUS, PARAINFLUENZA VIRUS, RESPIRATORY SYNCYTIAL VIRUS, RHINOVIRUS), INCLUDES MULTIPLEX REVERSE TRANSCRIPTION, WHEN PERFORMED, AND MULTIPLEX AMPLIFIED PROBE TECHNIQUE, MULTIPLE TYPES OR SUBTYPES, 12-25 TARGETS
Source: CMS coverage guidance
CPT 87632high
INFECTIOUS AGENT DETECTION BY NUCLEIC ACID (DNA OR RNA); RESPIRATORY VIRUS (EG, ADENOVIRUS, INFLUENZA VIRUS, CORONAVIRUS, METAPNEUMOVIRUS, PARAINFLUENZA VIRUS, RESPIRATORY SYNCYTIAL VIRUS, RHINOVIRUS), INCLUDES MULTIPLEX REVERSE TRANSCRIPTION, WHEN PERFORMED, AND MULTIPLEX AMPLIFIED PROBE TECHNIQUE, MULTIPLE TYPES OR SUBTYPES, 6-11 TARGETS
Source: CMS coverage guidance
CPT 0564Uhigh
INFECTIOUS DISEASE (BACTERIAL AND/OR VIRAL RESPIRATORY TRACT INFECTION), PATHOGEN-SPECIFIC NUCLEIC ACID (DNA OR RNA), 10 VIRAL TARGETS AND 4 BACTERIAL TARGETS, QUALITATIVE RT-PCR, UPPER RESPIRATORY SPECIMEN, EACH PATHOGEN REPORTED AS POSITIVE OR NEGATIVE
Source: CMS coverage guidance

Coding guidelines

Common synonyms

Encounter for antineoplastic chemotherapy

Frequently asked questions

Code details

CodeZ51.11
SystemICD10
Display nameEncounter for antineoplastic chemotherapy
ChapterFactors influencing health status and contact with health services (Z00-Z99)
BlockEncounters for other specific health care

Flags

BillableYes
Valid clinical useYes

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

Index terms

Matched terms
Chemotherapy(session) (for)Chemotherapy(session) (for)Encounter(with health service) (for)Maintenance(encounter for)

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.

ICD-10 Code Z51.11 for Encounter for antineoplastic chemotherapy | HealthAssure