CPT code 88341: Immunostain, each additional single antibody2026 Medicare rate & RVUs in Massachusetts
Report 88341 for each additional distinct single-antibody immunostain on a specimen after its initial single-antibody stain is reported with 88342.
Medicare pays $98.42–$109.55 for 88341 in the office in Massachusetts, from Rest of Massachusetts to Metropolitan Boston, MA. Which amount applies depends on the service address.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
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On this page 9 sections
What 88341 covers
This service covers another single-antibody immunohistochemistry or immunocytochemistry stain on a specimen after its first single-antibody stain. A laboratory applies a distinct antibody, such as a keratin or CD marker, to tissue sections or cytology material. A pathologist interprets the staining to help classify a carcinoma, lymphoma, or other lesion. Hospital pathology departments and independent laboratories perform the staining; the specimen may also have a separately reported surgical pathology examination.
Report one unit for each distinct additional single-antibody stain per specimen, not for each slide or tissue block. Report the initial single-antibody stain on each separately identified specimen with 88342; document the specimen, antibodies tested, and results. Control slides do not generate additional units. As an add-on, 88341 must accompany a primary procedure and is paid within that procedure’s global period. Modifier 26 identifies the pathologist’s interpretation, and modifier TC identifies the laboratory’s staining, reagents, and staff work when components are billed separately. Billing without either modifier identifies the global service.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
Where 88341 pays more and less in Massachusetts
| Payment locality | Office | Facility |
|---|---|---|
| Metropolitan Boston, MA | $109.55 | Unavailable |
| Rest of Massachusetts | $98.42 | Unavailable |
How the 88341 rate is calculated
Each of 88341’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 88341
RVUs × geographic indexes × conversion factor
Work0.55
0.55 RVUs× 1.000 GPCI
Practice expense2.26
2.26 RVUs× 1.000 GPCI
Malpractice0.01
0.01 RVUs× 1.000 GPCI
Adjusted RVUs
2.8200
Conversion factor
$33.4009
Medicare rate
$94.19
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 88341
The CMS indicators that decide how 88341 is paid alongside other services.
CMS payment indicators · 88341
Immunostain, each additional single antibody
| Rule | CMS value | What it means |
|---|---|---|
| Global period | ZZZ | Add-on code: falls within the primary procedure’s global period. |
| Multiple procedures | 0 | No multiple-procedure reduction. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 0 | Not paid without supporting documentation. |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 1 | Diagnostic test with separate professional (26) and technical (TC) components. |
What modifiers do to the payment
Modifier 26 · payment effect
With and without the modifier
88341 without 26 · national office
$94.19
Immunostain, each additional single antibody
88341-26 · Professional component
$26.72
Pays only the interpretation and report.
88341 compared with similar codes
Compare codes · National
5 codes, side by side
How to choose
- 88342Antibody stainFirst single antibody per specimen
- 88342 reports the initial single-antibody stain on a specimen. 88341 reports each additional distinct single-antibody stain on that specimen and is an add-on code.
- 88344ImmunostainMultiplex antibody procedure
- 88344 reports a multiplex procedure producing distinguishable results from multiple antibodies. Report 88341 for an additional separate single-antibody stain.
- 88360Tumor IHC scoringManual quantitative, per antibody
- 88360 reports manual morphometric analysis of a tumor immunostain. Do not also report 88341 for that antibody on the same specimen.
- 88350ImmunofluorescenceEach additional antibody stain
- 88350 reports an additional immunofluorescence antibody stain, such as in direct immunofluorescence of renal or skin tissue. 88341 reports an additional immunohistochemistry or immunocytochemistry single-antibody stain.
88341 billing questions
How do I split units between 88342 and 88341 when several specimens are stained?
Report 88342 for the initial single-antibody stain on each separately identified specimen. Report one unit of 88341 for each distinct additional single-antibody stain on that specimen, not for another slide or block stained with the same antibody.
Can 88341 be billed without a primary procedure?
No. It is an add-on code; report it with 88342 for the initial single-antibody stain on the same specimen.
When is a stain reported with 88344 rather than 88341?
Use 88344 for a multiplex stain procedure that produces distinguishable results from multiple antibodies. Use 88341 for an additional, separate single-antibody stain on the specimen.
Can 88341 be reported for the same antibody quantified with 88360 or 88361?
No. Do not also report a qualitative immunostain code for the same antibody on the same specimen when its morphometric analysis is reported with 88360 or 88361.
Which modifier identifies the pathologist’s interpretation when another entity stains the slides?
Report the separately billed interpretation with modifier 26; modifier TC identifies the separately billed technical work. When one entity bills both components, report the global service without either modifier.
Do control slides count as additional units?
No. Positive and negative control slides do not generate additional units of 88341.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
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