CPT Code 10036: Soft tissue localization, add-on billing guide

Key Takeaways

CPT Code 10036 describes percutaneous placement of a soft tissue localization device for each additional lesion beyond the first.

It is an add-on code: 10036 cannot be billed alone and must always be paired with primary code CPT 10035.

Imaging guidance is bundled into 10036’s descriptor, so billing a separate guidance code (e.g., 76942) alongside it risks claim denial.

Pabau’s claims management software tracks add-on code pairings and documents lesion counts to reduce billing errors and audit exposure.

Most soft tissue localization billing errors happen at exactly the moment coders assume a procedure was straightforward. When a radiologist places devices across multiple lesions in a single session, the add-on code logic is where claims quietly unravel.

CPT Code 10036 handles those additional lesions, but its rules around pairing, imaging guidance bundling, and documentation are strict enough that a single mistake can trigger a denial or, worse, an audit flag.

This reference covers everything billing professionals and coders need: the official descriptor, the primary/add-on pairing with CPT 10035, applicable modifiers, Medicare and commercial reimbursement rates, ICD-10 diagnosis pairings, and the billing errors that generate the most denials. Verify current Medicare rates directly through the CMS Physician Fee Schedule, as MPFS figures update annually.

CPT Code 10036: Definition and official descriptor

CPT Code 10036 is classified under the Surgery section of the AMA CPT code set, specifically within Introduction and Removal Procedures on the Skin — the same subsection that covers many of the skin-directed procedures practices running dermatology EMR software bill day to day. The official descriptor reads:

Placement of soft tissue localization device(s) (e.g., clip, metallic pellet, wire/needle, radioactive seeds), percutaneous, including imaging guidance; each additional lesion (List separately in addition to code for primary procedure)

Three elements of this descriptor carry direct billing implications. First, the parenthetical device list is illustrative, not exhaustive. Clips, metallic pellets, wire/needle hookwires, and radioactive seeds are all covered.

Second, “percutaneous” signals the approach: the device is placed through the skin under image guidance, not via open incision. Third, “each additional lesion” confirms this is a per-lesion add-on, reportable multiple times within a single encounter when supported by documentation.

CPT 10035 vs 10036: Primary and add-on code pairing

Understanding the 10035/10036 relationship is the single most important billing concept for this code pair. CPT 10035 is the base code, covering placement of a soft tissue localization device for the first lesion, including imaging guidance. CPT Code 10036 picks up every additional lesion beyond that first one.

A patient presenting with three lesions requiring device placement would generate one unit of 10035 and two units of 10036 on the same claim. The AAPC CPT code reference confirms this per-lesion stacking structure. Documentation must identify each lesion individually, not simply state “multiple lesions” as a collective entry.

The AMA CPT Assistant (June 2016) provides authoritative guidance on both codes and confirms the “list separately” instruction as an absolute requirement: 10036 submitted without 10035 on the same claim will be denied by virtually every payer.

Procedure description and clinical context for soft tissue localization device placement

Soft tissue localization is a pre-surgical or diagnostic procedure that marks a non-palpable target within tissue so a surgeon can locate and excise it precisely. CPT 10035 and 10036 were created specifically for localization outside the breast, most often in the axilla or groin.

The AMA’s own clinical example for these codes is a patient with axillary lymph node metastases from breast cancer, whose positive node is marked before neoadjuvant chemotherapy so the surgical team can still find it once treatment shrinks or clears the visible tumor.

When the device goes into the breast itself, a different code family applies instead. Use 19281-19288 for placement without biopsy, or 19081-19086 when it’s combined with a biopsy. Reporting 10035/10036 for a breast lesion, or a breast-specific code for an axillary or groin lesion, is a common source of denials and post-payment audit findings.

Practices running plastic surgery EMR workflows handle these cases across radiology, surgery, and billing departments in the same episode of care, which is exactly why incomplete documentation at the localization stage creates downstream claim complications. Coders working with CPT Code 10036 should understand the device types the code covers, because the descriptor’s parenthetical list determines which procedures qualify.

• Clip or metallic clip: A small metal marker deployed at the biopsy site. Commonly used after needle biopsy to mark the lesion location for future surgical reference.
• Metallic pellet: A tiny metal bead placed to mark a non-palpable lesion, similar to a clip but in pellet form.
• Wire/needle (hookwire): A thin wire with a barbed or hooked tip inserted through the skin and anchored near the target lesion. When it marks a lymph node outside the breast, 10035/10036 apply; the same hookwire technique placed inside the breast falls under 19281-19288 instead.
• Radioactive seeds: Radioactive seed localization (RSL) uses a small radioactive pellet placed days before surgery. The surgeon uses a gamma probe to locate it intraoperatively. Note that radioactive seed use is subject to NRC and applicable state radiation safety regulations beyond CPT billing rules.

Imaging guidance, whether ultrasound, fluoroscopy, or mammographic, is already included in the descriptor for both 10035 and 10036. Billing a separate imaging guidance code (such as 76942 for ultrasound guidance or 77002 for fluoroscopic guidance) alongside either code creates a bundling conflict and will typically result in the additional guidance code being denied.

Applicable modifiers for CPT Code 10036

Modifier selection for CPT Code 10036 follows standard add-on code conventions with a few specific considerations. Because 10036 is an add-on code, modifier 51 (multiple procedures) is not applicable. The AMA designates add-on codes as modifier 51 exempt.

Confirm modifier requirements with the applicable payer’s fee schedule or LCD before appending modifiers not validated by internal billing policy. Some Medicare Administrative Contractors (MACs) have specific modifier expectations for bilateral or repeat localization procedures.

Reimbursement and fee schedule for CPT Code 10036

Reimbursement for CPT Code 10036 varies by payer, geographic locality, and place of service. Medicare rates are set through the Medicare Physician Fee Schedule (MPFS) and updated each January 1. Always verify current figures using the CMS Physician Fee Schedule rather than relying on prior-year data.

For a quick, unofficial cross-check of work RVU values, the FastRVU RVU lookup tool can be handy. It’s a free, independently run calculator with no official CMS or AMA endorsement, though its underlying data is CMS-derived. Treat the CMS MPFS lookup above as the only authoritative source for confirming payment rates.

Medicare reimbursement

Medicare reimburses 10036 as an add-on code at a reduced rate relative to the primary procedure 10035, consistent with MPFS add-on code policy. Rates differ between facility and non-facility settings.

Because MPFS dollar amounts change annually and vary by geographic practice cost index (GPCI) locality, this article does not publish specific dollar figures. Pull current rates for your locality directly from the CMS MPFS lookup, selecting the current year and your provider’s MAC jurisdiction.

Facility vs non-facility rates

Place of service determines which rate schedule applies. When the procedure is performed in a facility setting (hospital outpatient department, ambulatory surgery center), the physician component is reimbursed at the facility rate, which is lower than the non-facility rate. The facility itself bills separately for overhead and equipment costs.

In a non-facility setting (office or freestanding imaging center not classified as a facility), the physician bears the practice expense and receives the higher non-facility rate to offset those costs. Selecting the wrong place of service code on the claim form is one of the most common reasons 10036 claims are returned for correction.

Commercial payer rates vary by contract and are not publicly mandated. Rates from commercial insurers typically fall within a range above or below the Medicare rate depending on the negotiated fee schedule. Contact each payer directly or consult your contract for specific commercial reimbursement amounts.

Billing guidelines for CPT Code 10036

Accurate billing for CPT Code 10036 depends on understanding its add-on code constraints. The HIPAA-compliant claims documentation requirements that govern electronic submission apply here just as with any other CPT code, but the add-on rules create additional layers of specificity.

• Always pair with 10035: Report 10036 only when 10035 also appears on the same claim for the same date of service. A standalone 10036 will be denied without exception.
• Document each lesion separately: The operative or procedure report must identify each lesion by location, size, and device type placed. Generalizing to “three lesions” without individual descriptions does not support multiple units of 10036.
• Do not unbundle imaging guidance: Both 10035 and 10036 include imaging guidance in their descriptors. Billing 76942 (ultrasound guidance), 77002 (fluoroscopic guidance), or 77021 (MRI guidance) in addition to either code creates an unbundling violation.
• Modifier 51 is exempt: As an add-on code, 10036 does not accept modifier 51. Appending it may cause rejection or require correction.
• Verify LCD coverage before billing: MACs issue Local Coverage Determinations specifying which ICD-10 diagnosis codes support medical necessity for localization procedures. Billing with a non-covered diagnosis code will result in denial regardless of the procedure being clinically appropriate.

Good clinical documentation requirements for add-on codes like 10036 are non-negotiable. The procedure note must be specific enough that an auditor reviewing the claim can verify each additional lesion independently.

Common billing errors and how to avoid them

Most denials for CPT Code 10036 fall into a small number of recurring patterns. Identifying them ahead of submission is far cheaper than correcting a rejected claim.

• Reporting 10036 without 10035: The most common error. Even if the coder knows a primary procedure was performed, the claim must reflect it explicitly. Systems that auto-populate CPT codes from charge capture need to be configured to flag add-on codes submitted without their primary code.
• Billing imaging guidance separately: Coders unfamiliar with the bundled imaging guidance in 10036’s descriptor sometimes add 76942 or 77002 to the claim. This creates a bundling edit that results in the additional code being denied or the claim being returned.
• Incorrect modifier application: Appending modifier 51 to 10036 is incorrect. Some billing systems will accept it without warning, but payers will reject or re-price the claim.
• Vague lesion documentation: Procedure notes that mention “multiple lesions” without identifying each one individually do not support multiple units of 10036. Each unit needs its own documented lesion.
• Using an unsupported ICD-10 code: If the diagnosis code on the claim is not listed in the applicable MAC’s LCD for localization procedures, the claim will deny for medical necessity. Cross-check diagnosis codes against the relevant LCD before submission.

Reviewing how documentation rules apply to a very different code, like ADHD screening CPT code billing, can help teams build consistent internal policies that apply to 10036 as well.

Tired of chasing down add-on code denials?

Pabau's claims management tools help billing teams flag missing primary codes, track lesion-level documentation, and submit cleaner claims the first time.

Book a demo

Supported ICD-10 diagnosis codes for CPT Code 10036

Medical necessity for CPT Code 10036 must be supported by an appropriate ICD-10 diagnosis code. Because the code is reserved for soft tissue sites outside the breast, the diagnoses that support it typically involve metastatic lymph node involvement or a more general finding of localized enlarged lymph nodes such as R59.0.

Always verify the specific diagnosis code pairings against your MAC’s applicable LCD before billing, as covered diagnoses vary by jurisdiction.

The table above reflects commonly paired diagnoses, not a comprehensive coverage list. Pabau’s diagnostic-codes library has dedicated guides for C77.8 and D36.0 if you need the full diagnostic criteria behind either code. Check the applicable MAC LCD for soft tissue localization procedures before finalizing your diagnosis code selection.

Related CPT codes for soft tissue localization procedures

CPT 10036 sits within a broader family of localization and breast procedure codes. Coders working with soft tissue localization billing should be familiar with related codes to avoid misassignment.

Comparing workflows across related code articles, such as coaching CPT codes reference and procedure code fee schedules, can help billing teams build consistent cross-code verification habits.

Coders should also distinguish 10035/10036 from percutaneous biopsy codes in the same numeric range: 10009 and its add-on 10010 cover fine needle aspiration with CT guidance, not device placement for later surgical localization.

The key distinction between 10035/10036 and the 19281-19288 series is anatomical, not just methodological. The 19281-19288 range covers breast-specific device placement using distinct imaging modalities (mammographic, stereotactic, ultrasound, MRI).

Codes 10035/10036 apply to soft tissue localization outside the breast, most often axillary or inguinal lymph nodes, using a percutaneous approach. A breast lesion diagnosed as R92.8, for example, pairs with one of the 19281-19288 codes regardless of imaging modality, not with 10035/10036.

How Pabau supports accurate CPT Code 10036 billing

Add-on code billing failures rarely come from coders not knowing the rules. They come from workflows that have no systematic checkpoint for those rules. When a practice sees high volumes of localization procedures across multiple radiologists, the risk of 10036 being submitted without 10035, or with an unsupported diagnosis code, increases with every manual step in the process.

Practice management software like Pabau gives billing teams the infrastructure to catch these errors before claims leave the practice. Its claims management software flags missing primary codes automatically, and structured patient intake software captures lesion-specific data at the point of care, building the audit trail that supports each unit of 10036 on the claim.

• Add-on code pairing validation: Flag claims where 10036 appears without a corresponding 10035 on the same date of service before submission.
• Lesion-level documentation: Structured procedure notes capture each lesion’s anatomical location, device type, and imaging guidance method individually, supporting multi-unit reporting.
• Diagnosis code verification: Cross-reference submitted ICD-10 codes against LCD coverage criteria to catch medical necessity mismatches before the claim reaches the payer.
• Audit trail for multiple units: When 10036 is reported multiple times for multiple additional lesions, the documentation for each unit is stored and retrievable in the event of a payer audit.

For practices using Pabau as their practice management software, the billing and documentation workflows connect directly, reducing the manual handoff steps where add-on code errors most often originate.

Conclusion

CPT Code 10036 is straightforward when its rules are followed precisely: always pair it with 10035, never bill imaging guidance separately, and document every additional lesion individually. Practices run into trouble when clinical documentation and claim submission aren’t connected, so the add-on code pairing gets lost and the lesion count becomes a single vague note.

Pabau’s structured documentation and claims management tools connect those two ends of the process, so the data captured at point of care flows directly into a clean, supportable claim. To see how Pabau handles add-on code workflows in practice, book a demo.

Continue your research

Billing for image-guided drainage procedures? CPT Code 10030 covers fluid collection drainage documentation and reimbursement.

Need the add-on code for bone debridement? CPT Code 11047 breaks down billing for each additional debrided segment.

Handling axillary hidradenitis excisions? CPT Code 11450 walks through the coding rules for these excision procedures.

Frequently asked questions