Summary & Overview

HCPCS M1195: Surgical Pathology Report Missing MMR/MSI Impression or Recommendation

HCPCS Level II code M1195 captures surgical pathology reports that omit an impression or conclusion, or omit recommendations regarding testing for mismatch repair (MMR) by immunohistochemistry or microsatellite instability (MSI) by DNA-based testing, with no reason documented. This code highlights gaps in reporting completeness for tumor testing that can affect downstream clinical decision-making and quality measurement.

Key national payers in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of what the code represents, the clinical context for reporting MMR/MSI testing status in surgical pathology, and why clear documentation matters for quality programs and claims processing. The publication provides benchmarking context where available, summaries of payer coverage themes, and identification of reporting and coding considerations related to pathology documentation standards.

The content addresses how the code is used in pathology workflows and common service settings, summarizes payer presence, and outlines where data is not available. This national-level overview is intended for revenue cycle, pathology, and compliance professionals seeking clarity on the clinical and billing meaning of HCPCS Level II code M1195.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicareM1195HCPCS Level IIsurgical pathologyMMR testingMSI testingpathology reportingbilling and codingclinical documentationoncology diagnostics

Billing Code Overview

HCPCS Level II code M1195 describes surgical pathology reports that do not contain an impression or conclusion, or a recommendation for testing of MMR by immunohistochemistry, MSI by DNA-based testing status, or both, with no reason provided. The service type is surgical pathology reporting and documentation of tumor testing status. The typical site of service is pathology laboratory or hospital outpatient/inpatient pathology service where surgical specimens are examined and reports are issued.

Data not available in the input.

Clinical & Coding Specifications

Clinical Context

A surgical pathology report is generated after resection or biopsy of a tumor specimen from sites such as the colon, endometrium, ovary, or other organs. In this scenario a patient undergoes surgical excision of a suspected malignancy (for example, a segmental colectomy for a suspicious colonic mass). The specimen is submitted to the pathology laboratory for grossing, histologic processing, and microscopic interpretation. The pathologist issues a surgical pathology report describing tissue type, tumor grade, margins, lymphovascular invasion, and ancillary testing performed. The report, however, does not contain an explicit impression or conclusion addressing mismatch repair (MMR) status by immunohistochemistry or microsatellite instability (MSI) status by DNA-based testing, and no reason for omission is documented. Billing for this situation is captured by M1195.

Typical workflow steps:

Surgeon obtains specimen and directs submission to pathology.
Pathology performs gross examination, tissue fixation, embedding, sectioning, and staining (H&E).
Pathologist reviews slides and documents morphologic findings in a descriptive report.
Ancillary testing (IHC for MMR proteins or MSI DNA testing) may be considered but is not reported or concluded in the final report; no justification for omission is provided.
The laboratory bills M1195 when the surgical pathology report lacks an impression/conclusion or recommendation regarding MMR by IHC or MSI by DNA testing status and no reason is given.

Typical site of service: hospital-based pathology laboratory or independent clinical pathology/laboratory facility associated with inpatient or outpatient surgical services.

Coding Specifications

Modifier	Description	When to Use
`22`	Increased procedural services	Use when the pathology work required is substantially greater than typical and documentation supports increased complexity.
`23`	Unusual anesthesia	Rarely applicable for pathology billing; included in list but not typically used with `M1195`.
`52`	Reduced services	Use when a portion of the expected pathology service was not completed and is documented (partial service).
`53`	Discontinued procedure	Use if processing or interpretation was started but discontinued for documented clinical reasons.
`54`	Surgical care only	Not applicable to pathology professional billing; reserved for split surgical packages.
`55`	Postoperative management only	Not applicable to pathology billing.
`56`	Preoperative management only	Not applicable to pathology billing.
`62`	Two surgeons	Not applicable to pathology; included for completeness.
`AS`	Ambulatory surgery center facility	Use when the service is furnished in an ambulatory surgery center and reporting facility modifier is required by payer.
`CO`	Out-of-pocket costs under workers' compensation	Use when payer requires identification of services related to workers' compensation claims.
`CQ`	Service furnished by a PT in a team-based model	Not applicable to pathology; retained from provided list.
`FX`	Split/shared service — nonphysician practitioner	Use when a split/shared service applies and payor requires identification of the nonphysician practitioner component.
`FY`	Split/shared service — physician	Use when a split/shared service applies and payor requires identification of the physician component.
`QK`	Medical direction of two or more CRNAs	Not applicable to pathology; listed from input.
`QX`	CRNA service with medical direction by physician	Not applicable to pathology; listed from input.
`QY`	Medical direction of one CRNA by physician	Not applicable to pathology; listed from input.

Taxonomy Code	Specialty	Notes
207RH0000X	Anatomic and Clinical Pathology	Pathologists who interpret surgical specimens and issue reports including recommendations for ancillary testing.
2080P0006X	Hematopathology	Hematopathologists may be involved for hematologic malignancies requiring MMR/MSI considerations in specific contexts.
2084P0800X	Medical Laboratory Immunology	Laboratory specialists overseeing IHC testing for MMR proteins.
207L00000X	Clinical Laboratory	Clinical laboratory directors responsible for DNA-based MSI testing and molecular workflows.
2085R0201X	Molecular Genetic Pathology	Specialists performing and interpreting DNA-based MSI and molecular assays.

ICD-10 Code	Description	Clinical Relevance
`C18.9`	Malignant neoplasm of colon, unspecified	Colon cancers commonly require assessment of MMR/MSI status for prognosis and potential Lynch syndrome screening.
`C54.1`	Malignant neoplasm of endometrium	Endometrial carcinomas are frequently evaluated for MMR deficiency as part of tumor profiling and hereditary cancer evaluation.
`C56.9`	Malignant neoplasm of ovary, unspecified	Ovarian tumors may prompt MMR/MSI testing in differential hereditary syndromes and therapeutic considerations.
`D07.9`	Carcinoma in situ of breast, unspecified	In select tumor types, ancillary testing may be relevant; included as a site where pathology reports sometimes omit recommended molecular testing.
`R87.619`	Abnormal cytology of unspecified site of female genital tract	Abnormal findings can lead to surgical sampling where MMR/MSI assessment may later be relevant.

CPT Code	Description	Relationship to This Procedure
`88305`	Level IV surgical pathology, gross and microscopic examination	Common primary code for examination and reporting of surgical specimens; typically billed for histologic interpretation preceding or accompanying the `M1195` reporting context.
`88342`	Immunohistochemistry, each antibody stain	Used when MMR protein IHC is performed (e.g., MLH1, MSH2, MSH6, PMS2); if IHC is performed but not concluded in the report, this code documents the technical and interpretive work.
`81479`	Unlisted molecular pathology procedure	Used for DNA-based MSI testing when no specific CPT exists or when MSI testing is billed as an unlisted molecular assay.
`81445`	Tumor associated antigen testing (e.g., microsatellite instability) — note: payer-specific applicability	Used by some laboratories or payers for MSI testing when a specific reporting code is available; indicates DNA-based testing relevant to MMR/MSI status.
`88313`	Consultation and report of surgical pathology specimen by an outside pathologist	Used when an external pathology consult is requested for tumor interpretation including ancillary test recommendations; may occur when initial report lacks MMR/MSI impression.

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