C39.9: Malignant neoplasm of lower respiratory tract, part unspecified

C39.9, malignant neoplasm of lower respiratory tract, part unspecified, is listed as a covered diagnosis in 5 Medicare billing and coding articles that apply to 51 HCPCS Level II codes, including Q0512 (Pharmacy supply fee for oral anti-cancer, oral anti-emetic…), Q0511 (Pharmacy supply fee for oral anti-cancer, oral anti-emetic…), G0238 (Therapeutic procedures to improve respiratory function…). The articles come from 2 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 C39.9 as a covered diagnosis

CodeDescriptionMedicare coverageDMEPOS fee 2026 (state range)Articles listing it
Q0512Pharmacy supply fee for oral anti-cancer, oral anti-emetic or immunosuppressive drug(s); for a subsequent prescription in a 30-day periodSpecial coverage instructions apply—2
Q0511Pharmacy supply fee for oral anti-cancer, oral anti-emetic or immunosuppressive drug(s); for the first prescription in a 30-day periodSpecial coverage instructions apply—2
G0238Therapeutic procedures to improve respiratory function, other than described by g0237, one on one, face to face, per 15 minutes (includes monitoring)Carrier judgment—1
G0237Therapeutic procedures to increase strength or endurance of respiratory muscles, face to face, one on one, each 15 minutes (includes monitoring)Carrier judgment—1
G0239Therapeutic procedures to improve respiratory function or increase strength or endurance of respiratory muscles, two or more individuals (includes monitoring)Carrier judgment—1
J8999Prescription drug, oral, chemotherapeutic, nosSpecial coverage instructions apply—1
J8530Cyclophosphamide; oral, 25 mgSpecial coverage instructions apply—1
J8597Antiemetic drug, oral, not otherwise specifiedSpecial coverage instructions apply—1
J8610Methotrexate; oral, 2.5 mgSpecial coverage instructions apply—1
J8498Antiemetic drug, rectal/suppository, not otherwise specifiedSpecial coverage instructions apply—1
J0881Injection, darbepoetin alfa, 1 microgram (non-esrd use)Special coverage instructions apply—1
J0885Injection, epoetin alfa, (for non-esrd use), 1000 unitsSpecial coverage instructions apply—1
Q5106Injection, epoetin alfa-epbx, biosimilar, (retacrit) (for non-esrd use), 1000 unitsSpecial coverage instructions apply—1
J0882Injection, darbepoetin alfa, 1 microgram (for esrd on dialysis)Special coverage instructions apply—1
Q5105Injection, epoetin alfa-epbx, biosimilar, (retacrit) (for esrd on dialysis), 100 unitsSpecial coverage instructions apply—1
J0890Injection, peginesatide, 0.1 mg (for esrd on dialysis)Carrier judgment—1
Q4081Injection, epoetin alfa, 100 units (for esrd on dialysis)Special coverage instructions apply—1
Q5110Injection, filgrastim-aafi, biosimilar, (nivestym), 1 microgramSpecial coverage instructions apply—1
Q5125Injection, filgrastim-ayow, biosimilar, (releuko), 1 microgramCarrier judgment—1
Q5101Injection, filgrastim-sndz, biosimilar, (zarxio), 1 microgramSpecial coverage instructions apply—1
J1442Injection, filgrastim (g-csf), excludes biosimilars, 1 microgramSpecial coverage instructions apply—1
J1449Injection, eflapegrastim-xnst, 0.1 mgCarrier judgment—1
J1447Injection, tbo-filgrastim, 1 microgramSpecial coverage instructions apply—1
Q5108Injection, pegfilgrastim-jmdb (fulphila), biosimilar, 0.5 mgCarrier judgment—1
Q5111Injection, pegfilgrastim-cbqv (udenyca), biosimilar, 0.5 mgCarrier judgment—1

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

Medicare policy articles listing C39.9

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 C39 diagnoses (Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs)

Frequently asked questions

Does Medicare cover C39.9 (Malignant neoplasm of lower respiratory tract, part…)?

Medicare covers items and services, not diagnoses. 5 Medicare billing and coding articles list C39.9 as a covered diagnosis for 51 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 C39.9?

The Level II codes from the policies most specific to this diagnosis are Q0512 (Pharmacy supply fee for oral anti-cancer, oral anti-emetic…, 2 articles); Q0511 (Pharmacy supply fee for oral anti-cancer, oral anti-emetic…, 2 articles); G0238 (Therapeutic procedures to improve respiratory function…, 1 article); G0237 (Therapeutic procedures to increase strength or endurance…, 1 article); G0239 (Therapeutic procedures to improve respiratory function or…, 1 article). Code choice depends on the item supplied; check each code's descriptor.

Which Medicare policy articles list C39.9?

A56717 (Billing and Coding: Respiratory Therapy (Respiratory Care)); A52479 (Oral Anticancer Drugs - Policy Article); A56462 (Billing and Coding: Erythropoiesis Stimulating Agents (ESA)), and 2 more articles.

What is ICD-10-CM code C39.9?

C39.9 is the ICD-10-CM code for malignant neoplasm of lower respiratory tract, part unspecified, in category C39 (Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs), chapter 2: Neoplasms.

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 2: Neoplasms · All diagnoses · HCPCS lookup