M1166 HCPCS code: Pathology report for tissue specimens produced from wide local excisions or re-excisions
M1166 is the HCPCS Level II code for pathology report for tissue specimens produced from wide local excisions or re-excisions. Its Medicare coverage code is C (Carrier judgment): Coverage is decided by the Medicare contractor (MAC) case by case.
Code details
| Field | Value |
|---|---|
| Section | M codes — Medical services and quality measures |
| Coverage code | C — Carrier judgment |
| Pricing indicator | 00 — Not separately priced by Medicare |
| BETOS category | Z2 |
| Added | 2023-01-01 |
| Last action effective | 2023-01-01 |
What changed for M1166
- 2023-01-01: M1166 added to HCPCS Level II
- Next scheduled CMS quarterly update (HCPCS and DMEPOS fee schedule): 2027-01-01
Frequently asked questions
What is HCPCS code M1166?
M1166 is the HCPCS Level II code for pathology report for tissue specimens produced from wide local excisions or re-excisions. Short descriptor: "Path rpt tis spec wle/reexc".
Does Medicare cover M1166?
Coverage code C — Carrier judgment. Coverage is decided by the Medicare contractor (MAC) case by case.
Related M11 codes
- M1106 — The start of an episode of care documented in the medical record
- M1107 — Documentation stating patient has a diagnosis of a degenerative neurological condition such as als, ms, or parkinson's diagnosed at any time before or during the episode of care
- M1108 — Ongoing care not clinically indicated because the patient needed a home program only, referral to another provider or facility, or consultation only, as documented in the medical record
- M1109 — Ongoing care not medically possible because the patient was discharged early due to specific medical events, documented in the medical record, such as the patient became hospitalized or scheduled for surgery
- M1110 — Ongoing care not possible because the patient self-discharged early (e.g., financial or insurance reasons, transportation problems, or reason unknown)
- M1111 — The start of an episode of care documented in the medical record
- M1112 — Documentation stating patient has a diagnosis of a degenerative neurological condition such as als, ms, or parkinson's diagnosed at any time before or during the episode of care
- M1113 — Ongoing care not clinically indicated because the patient needed a home program only, referral to another provider or facility, or consultation only, as documented in the medical record
- M1114 — Ongoing care not medically possible because the patient was discharged early due to specific medical events, documented in the medical record, such as the patient became hospitalized or scheduled for surgery
- M1115 — Ongoing care not possible because the patient self-discharged early (e.g., financial or insurance reasons, transportation problems, or reason unknown)
- M1116 — The start of an episode of care documented in the medical record
- M1117 — Documentation stating patient has a diagnosis of a degenerative neurological condition such as als, ms, or parkinson's diagnosed at any time before or during the episode of care
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Next steps
- Run a reimbursement report for a device billed under M1166
- Watch M1166 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for M1166
Sources: CMS HCPCS Level II release October 2025; CMS DMEPOS fee schedule; CMS NCCI MUE tables; CMS Medicare utilization (physician and DME supplier files); CMS Medicare Coverage Database articles. Fees are Medicare allowables, not commercial rates. Not billing or legal advice.