CPT code 96405 – Intralesional chemotherapy administration

Key takeaways

CPT Code 96405 covers intralesional chemotherapy injection for up to 7 lesions per session. Each lesion beyond the seventh adds one unit of add-on code 96406.

96405 bills the administration service only. The chemotherapy drug is reported separately under its HCPCS J code on the same claim.

Medicare requires direct supervision for chemotherapy administration in the office (POS 11), where the higher non-facility rate applies.

The 2026 national Medicare payment for 96405 is about $84.50 in the office and $23.71 in a facility setting.

Pabau’s claim validation checks each 96405 claim for missing or invalid details before it leaves the practice. Errors get fixed before a payer sees them.

CPT Code 96405: Official descriptor and procedure overview

CPT Code 96405 is defined by the American Medical Association as: Chemotherapy administration, intralesional; up to and including 7 lesions.

The code covers the complete administration service when a physician or qualified healthcare professional injects a chemotherapy agent directly into a lesion or tumor mass. That includes pre- and post-injection observation and standard supplies.

Intralesional injection differs from subcutaneous or intramuscular routes. The needle enters the lesion itself, not the surrounding tissue, so the drug acts locally on the tumor cells.

Common indications include cutaneous malignancies, Kaposi’s sarcoma lesions, and certain wart-type neoplasms where systemic chemotherapy is not indicated or has failed.

In Pabau’s claims management software, each claim is pre-filled from the patient’s invoice. The treatment note with the lesion count and anatomic sites sits in the same patient record, so the biller codes from what the clinician documented.

The “up to and including 7 lesions” language is the threshold that separates 96405 from its add-on code. A session treating 3 lesions bills 96405 once. A session treating 10 lesions bills 96405 once plus 96406 three times (one unit per lesion beyond 7).

What CPT 96405 covers and what it excludes

The code bundles the professional service of administering the injection. That covers site preparation, the injection itself, and routine monitoring during and immediately after administration. The drug is not bundled.

CPT 96405 vs 96401: Key differences and when to use each

96401 covers non-hormonal antineoplastic chemotherapy given by subcutaneous or intramuscular injection, and 96402 covers the hormonal version. 96405 has no hormonal or non-hormonal split. It applies to any antineoplastic agent injected into the lesion, so the route decides the code, not the drug.

A common error is selecting 96401 when the note documents a tumor injection, because both codes sit in the same chemotherapy administration family. If the physician’s note says the needle entered the lesion, 96405 is correct, however the drug is usually given elsewhere.

Add-on code 96406: Billing beyond 7 lesions

CPT 96406 is the add-on code for each additional lesion injected beyond the 7-lesion threshold covered by 96405. It cannot be reported without 96405 as the parent code, and its units grow with the lesion count, as the chart below shows.

• 96405 first: Report once per session regardless of how many lesions fall within the threshold (1 through 7).
• 96406 for each additional lesion: If 10 lesions are treated, report 96406 x3 (lesions 8, 9, and 10).
• No standalone billing: 96406 alone is a billing error, and payers will deny it without the primary code.
• Lesion count documentation is the prerequisite: Every unit of 96406 requires a corresponding lesion site documented in the record. A note that says “multiple lesions” without counting them will fail audit.

Documentation requirements for CPT Code 96405

Complete documentation for an intralesional chemotherapy claim must include the following elements. Missing any one of them is the most reliable path to a denial.

1. Drug name and dose: The exact chemotherapy agent and the dose in appropriate units, such as mg. Add the lot number where NDC reporting requires it.
2. Lesion count and anatomic sites: The number of lesions injected and their location (e.g., “3 lesions, left forearm dorsal surface”). This count determines whether 96405 alone or 96405 plus units of 96406 is appropriate.
3. Route confirmation: The note must state intralesional administration explicitly. “Injected into lesion” or “intralesional injection” is sufficient. “Injection given” is not.
4. Medical necessity: The diagnosis code (ICD-10-CM) linked to the claim must support intralesional chemotherapy. A brief narrative justifying why this route was selected over systemic therapy strengthens the record for audit purposes.
5. Physician supervision: Document that the supervising physician was present in the office suite, or available through real-time audio-video, during the administration. This matters most for Medicare claims in the office setting.
6. Patient response and monitoring: A brief post-injection assessment note. Adverse reaction monitoring is bundled into 96405, so the record should show it happened.

Practices with a structured clean claim submission workflow complete these elements at the point of care, before the claim is generated.

J codes: Billing the drug alongside CPT 96405

CPT Code 96405 covers the administration service only. The chemotherapy drug itself is billed separately under the applicable HCPCS J code. This is the buy-and-bill model.

The practice purchases the drug, administers it, and bills both the administration code and the drug code on the same claim. In the medical billing process, that means every intralesional chemotherapy visit produces at least two claim lines.

NDC (National Drug Code) reporting is required by Medicare and many commercial payers when billing J codes. The NDC goes on the claim as a qualifier on the drug line, not as a separate line item. Missing NDC information is a common secondary denial reason for J code lines that otherwise look complete.

Medicare coverage and billing guidelines for CPT Code 96405

Medicare covers intralesional chemotherapy administration when the procedure meets medical necessity criteria under the applicable Local Coverage Determination (LCD). Coverage is not automatic. The diagnosis code on the claim must map to an indication covered under the relevant LCD for the administering contractor.

Place of service and reimbursement

The place of service code directly affects how much Medicare pays. In the office (POS 11), Medicare applies the non-facility rate, which is higher because practice expense is not shared with a facility. In an outpatient hospital (POS 22) or ASC, the facility rate applies and the facility bills a separate technical component.

In the office, chemotherapy administration is billed incident to the physician’s service, so it needs direct supervision. The physician does not need to be in the same room but must be immediately available to respond. Since January 1, 2026, that can mean presence in the office suite or real-time audio-video, though never audio-only.

The CY 2026 Physician Fee Schedule final rule made that virtual option permanent for incident-to services. It excludes services with a 010 or 090 global surgery period.

Pabau submits claims through its Claim.MD clearinghouse integration, which validates each claim and checks eligibility before the visit. Claim.MD connects to thousands of US payers, and its real-time eligibility checks cover over 400 of them.

2026 fee schedule: Reimbursement rates and RVU values for CPT 96405

The 2026 Medicare Physician Fee Schedule values for 96405 reflect the administration service only, not the drug. Rates vary by geographic practice cost index (GPCI), so use the CMS Physician Fee Schedule lookup for payment amounts by locality. The table below shows national unadjusted values as a baseline.

At the 2026 conversion factor, those totals work out to about $84.50 in the office and $23.71 in a facility. For locality-adjusted rates, use the FastRVU 2026 lookup tool. Commercial payers usually reimburse a contracted percentage of the Medicare rate, so check contract terms before estimating payment.

Common denial reasons for CPT 96405 and how to prevent them

Intralesional chemotherapy claims carry two lines, an administration code and a separately billed drug, and each must clear payer edits on its own. When a claim comes back, the full list of denial codes explains each remittance remark code.

• Missing lesion count: A frequent denial trigger. The record must state a specific number, not “multiple” or “several.” Prevention: Add a lesion count field to the procedure note template.
• Absent medical necessity documentation: Payers apply LCD criteria. A bare ICD-10 code without a supporting treatment plan narrative fails audits. Prevention: Attach the relevant LCD to the documentation checklist for intralesional administration.
• Wrong place of service code: Billing POS 11 for a procedure performed in a hospital outpatient department triggers an edit. Prevention: Confirm POS at scheduling before the claim is drafted.
• Missing J code or NDC: A claim with 96405 but no drug line is incomplete. Prevention: Use code-pairing rules in your billing system to require a J code when 96405 is selected.
• Unbundling error with E/M: Billing a same-day evaluation and management code without modifier 25 triggers a bundling edit. Prevention: Attach modifier 25 to the E/M when a separately identifiable service is documented.
• 96406 without 96405: The add-on code alone returns an immediate denial. Prevention: Configure your billing system to require 96405 as a prerequisite before 96406 can be selected.

A structured denial management workflow catches these errors before submission rather than after remittance. That saves the cost of reworking claims and resubmitting them within payer timely-filing windows.

How Pabau cuts denials on intralesional chemotherapy claims

The documentation-to-claim chain for intralesional chemotherapy has more failure points than a standard procedure code. Lesion count, anatomic sites, drug and dose, J code, NDC and POS must all match between the clinical note and the claim.

Pabau keeps the treatment note, the invoice and the claim in one patient record. Say a clinician records “3 lesions, dorsal left forearm, bleomycin 15 units.” The biller then opens a claim pre-filled from that visit’s invoice instead of re-keying it. For out-of-network patients, the superbill comes from the same record.

Before submission, Pabau’s claim validation scrubs each claim for missing or invalid details. A claim the payer rejects is flagged Needs action with the reason, so your team fixes it inside the filing window instead of weeks later.

Simplify chemotherapy billing from documentation to payment

Pabau connects clinical notes, drug administration records, and claim generation in one workflow. See how integrated billing reduces intralesional chemotherapy denials.

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Conclusion

CPT Code 96405 rewards the practice that counts. A lesion count written as a number, a stated intralesional route, and a J code on the same claim settle most of what payers check.

Build those three fields into your procedure note template before the next intralesional session. The trade-off is a minute of charting per visit against a denied claim that can take weeks to rework. A revenue cycle review of how your drug lines are coded and posted is the natural next step.

Book a demo to see how Pabau carries the lesion count from the treatment note to a validated 96405 claim.

Continue your research

Need to understand how clearinghouse submissions work for chemotherapy claims? Medical claims clearinghouse guide explains how claims route from practice to payer and where edits catch errors.

Looking for the 837P file format used to submit CPT 96405 electronically? 837 EDI file guide covers the transaction set structure and required fields for professional claims.

Want to understand how electronic remittance advice works after a 96405 claim pays or denies? Electronic remittance advice (ERA) guide explains CARC and RARC codes returned on 835 transactions.

Billing fluorouracil with an intralesional injection? HCPCS code J9190 covers the 500 mg unit math and documentation for the drug line.

Is the injected agent hormonal and given subcutaneously? CPT code 96402 explains when the hormonal route code applies instead.

Frequently asked questions