Z51.11: Encounter for antineoplastic chemotherapy

Z51.11, encounter for antineoplastic chemotherapy, is listed as a covered diagnosis in 13 Medicare billing and coding articles that apply to 90 HCPCS Level II codes, including J1559 (Injection, immune globulin (hizentra), 100 mg), J1555 (Injection, immune globulin (cuvitru), 100 mg), J1575 (Injection, immune globulin/hyaluronidase, (hyqvia), 100 mg…). The articles come from 7 Medicare contractors. A listed diagnosis supports medical necessity only; coverage still depends on the LCD's criteria and on documentation in the medical record.

HCPCS Level II codes with Z51.11 as a covered diagnosis

CodeDescriptionMedicare coverageDMEPOS fee 2026 (state range)Articles listing it
J1559Injection, immune globulin (hizentra), 100 mgCarrier judgment—2
J1555Injection, immune globulin (cuvitru), 100 mgCarrier judgment—2
J1575Injection, immune globulin/hyaluronidase, (hyqvia), 100 mg immuneglobulinCarrier judgment—2
J1558Injection, immune globulin (xembify), 100 mgCarrier judgment—2
J1569Injection, immune globulin, (gammagard liquid/gammagard liquid erc), 500 mgSpecial coverage instructions apply—2
J1561Injection, immune globulin, (gamunex-c/gammaked), non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—2
J1551Injection, immune globulin (cutaquig), 100 mgCarrier judgment—2
J1459Injection, immune globulin (privigen), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—2
J1576Injection, immune globulin (panzyga), intravenous, non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—2
J1557Injection, immune globulin, (gammaplex), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—2
J1556Injection, immune globulin (bivigam), 500 mgCarrier judgment—2
J1568Injection, immune globulin, (octagam), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—2
J1566Injection, immune globulin, intravenous, lyophilized (e.g., powder), not otherwise specified, 500 mgSpecial coverage instructions apply—2
J1554Injection, immune globulin (asceniv), 500 mgCarrier judgment—2
J1572Injection, immune globulin, (flebogamma/flebogamma dif), intravenous, non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—2
J1552Injection, immune globulin (alyglo), 500 mgCarrier judgment—2
J1553Injection, immune globulin (yimmugo), 100 mgCarrier judgment—2
J1577Injection, immune globulin (qivigy), 100 mgCarrier judgment—2
A9500Technetium tc-99m sestamibi, diagnostic, per study doseCarrier judgment—2
A9502Technetium tc-99m tetrofosmin, diagnostic, per study doseCarrier judgment—2
A9505Thallium tl-201 thallous chloride, diagnostic, per millicurieCarrier judgment—2
A9512Technetium tc-99m pertechnetate, diagnostic, per millicurieCarrier judgment—2
A9560Technetium tc-99m labeled red blood cells, diagnostic, per study dose, up to 30 millicuriesCarrier judgment—2
A9538Technetium tc-99m pyrophosphate, diagnostic, per study dose, up to 25 millicuriesCarrier judgment—2
A9501Technetium tc-99m teboroxime, diagnostic, per study doseCarrier judgment—2

65 more codes are listed. See every code with payment by region in Caduvo.

Medicare policy articles listing Z51.11

A diagnosis listed as covered in a billing and coding article supports medical necessity for the article's codes; it does not guarantee payment. Coverage depends on the LCD's criteria, the contractor's jurisdiction and documentation in the medical record.

Other Z51 diagnoses (Encounter for other aftercare and medical care)

Frequently asked questions

Does Medicare cover Z51.11 (Encounter for antineoplastic chemotherapy)?

Medicare covers items and services, not diagnoses. 13 Medicare billing and coding articles list Z51.11 as a covered diagnosis for 90 HCPCS Level II codes: the diagnosis can support medical necessity for those codes, but payment still depends on the LCD's coverage criteria and the medical record.

Which HCPCS codes can be billed with ICD-10 Z51.11?

The Level II codes from the policies most specific to this diagnosis are J1559 (Injection, immune globulin (hizentra), 100 mg, 2 articles); J1555 (Injection, immune globulin (cuvitru), 100 mg, 2 articles); J1575 (Injection, immune globulin/hyaluronidase, (hyqvia), 100 mg…, 2 articles); J1558 (Injection, immune globulin (xembify), 100 mg, 2 articles); J1569 (Injection, immune globulin, (gammagard liquid/gammagard…, 2 articles). Code choice depends on the item supplied; check each code's descriptor.

Which Medicare policy articles list Z51.11?

A56786 (Billing and Coding: Immune Globulin); A57778 (Billing and Coding: Immune Globulin); A56494 (Billing and Coding: Cardiovascular Nuclear Medicine), and 10 more articles.

What is ICD-10-CM code Z51.11?

Z51.11 is the ICD-10-CM code for encounter for antineoplastic chemotherapy, in category Z51 (Encounter for other aftercare and medical care), chapter 22: Factors influencing health status and contact with health services.

Next steps

Sources: CMS Medicare Coverage Database billing and coding articles (covered ICD-10 code lists and HCPCS links); ICD-10-CM FY2026; CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026 (non-rural state fees). Not billing or legal advice.

Chapter 22: Factors influencing health status and contact with health services · All diagnoses · HCPCS lookup