CPT code 88366: FISH interpretation, interpretation and report2026 Medicare rate & RVUs in Baltimore area, MD
Reports the diagnostic interpretation of in situ hybridization findings, such as fluorescent probe results in tumor tissue, for a specific clinical question.
In Baltimore area, MD, Medicare pays $282.48 for 88366 in the office.
Check a contract rate as a % of Medicare · 88366 nationwide
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 11 sections
What 88366 covers
A pathologist evaluates in situ hybridization findings, including fluorescent in situ hybridization (FISH) signals in tissue or cytology specimens, and prepares a diagnostic interpretation and report. Oncology specimens may be assessed for gene or chromosome changes relevant to tumor classification or treatment decisions. The report connects the probe findings with the specimen and clinical question; this service is distinct from performing the probe-staining procedure itself.
Report 88366 for the interpretation and report associated with an in situ hybridization study, supported by documentation identifying the specimen, test findings, and diagnostic conclusion. CMS recognizes professional and technical components: modifier 26 identifies the professional interpretation, modifier TC identifies the technical service, and billing without either modifier represents the global service. The professional component reflects the physician’s interpretation; the technical component covers equipment and staff involved in the test.
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.
How Baltimore area, MD compares for 88366
Across 109 of 109 payment localities, the office rate for 88366 runs from $233.05 in Arkansas to $367.79 in San Benito County, CA. Baltimore area, MD pays $282.48. The RVUs are the same everywhere; the geographic indexes change the dollars.
- Baltimore area, MD · this page$282.48
- Rest of Maryland · Maryland$268.18−$14.30
- Los Angeles, CA · California$307.30+$24.82
- Washington, DC area · District of Columbia$307.31+$24.83
- Miami, FL · Florida$276.41−$6.07
- Chicago, IL · Illinois$268.33−$14.15
- Manhattan, NY · New York$304.77+$22.29
Other areas in Maryland first, then benchmark localities. Bars start at $0.
Every other payment area
| Payment locality | Office | Facility |
|---|---|---|
| AlaskaAlaska | $299.34 | — |
| AlabamaAlabama | $236.69 | — |
| ArkansasArkansas | $233.05 | — |
| ArizonaArizona | $258.08 | — |
| Bakersfield, CACalifornia | $286.90 | — |
| Chico, CACalifornia | $286.72 | — |
| El Centro, CACalifornia | $286.73 | — |
| Fresno, CACalifornia | $286.72 | — |
| Hanford, CACalifornia | $286.72 | — |
| Madera, CACalifornia | $286.72 | — |
| Merced, CACalifornia | $286.72 | — |
| Modesto, CACalifornia | $286.72 | — |
| Napa, CACalifornia | $338.15 | — |
| Oxnard, CACalifornia | $306.50 | — |
| Redding, CACalifornia | $286.72 | — |
| Rest of CaliforniaCalifornia | $286.72 | — |
| Riverside, CACalifornia | $287.19 | — |
| Sacramento, CACalifornia | $302.46 | — |
| Salinas, CACalifornia | $301.36 | — |
| San Diego, CACalifornia | $309.60 | — |
| Marin County, CACalifornia | $359.94 | — |
| San Francisco, CACalifornia | $359.89 | — |
| San Benito County, CACalifornia | $367.79 | — |
| Santa Clara County, CACalifornia | $367.61 | — |
| San Luis Obispo, CACalifornia | $296.33 | — |
| Santa Cruz, CACalifornia | $313.47 | — |
| Santa Maria, CACalifornia | $302.81 | — |
| Santa Rosa, CACalifornia | $316.74 | — |
| Stockton, CACalifornia | $286.72 | — |
| Vallejo, CACalifornia | $338.08 | — |
| Visalia, CACalifornia | $286.72 | — |
| Yuba City, CACalifornia | $286.72 | — |
| ColoradoColorado | $279.70 | — |
| ConnecticutConnecticut | $283.50 | — |
| DelawareDelaware | $262.59 | — |
| Fort Lauderdale, FLFlorida | $269.19 | — |
| Rest of FloridaFlorida | $256.04 | — |
| Atlanta, GAGeorgia | $269.17 | — |
| Rest of GeorgiaGeorgia | $241.33 | — |
| Hawaii, Guam, HIHawaii | $295.25 | — |
| IowaIowa | $245.40 | — |
| IdahoIdaho | $246.62 | — |
| East St. Louis, ILIllinois | $248.68 | — |
| Rest of IllinoisIllinois | $246.52 | — |
| Suburban Chicago, ILIllinois | $272.55 | — |
| IndianaIndiana | $248.20 | — |
| KansasKansas | $243.09 | — |
| KentuckyKentucky | $240.29 | — |
| New Orleans, LALouisiana | $252.20 | — |
| Rest of LouisianaLouisiana | $239.45 | — |
| Metropolitan Boston, MAMassachusetts | $310.06 | — |
| Rest of MassachusettsMassachusetts | $277.42 | — |
| Rest of MaineMaine | $246.82 | — |
| Southern Maine, MEMaine | $262.70 | — |
| Detroit, MIMichigan | $258.30 | — |
| Rest of MichiganMichigan | $245.94 | — |
| MinnesotaMinnesota | $270.74 | — |
| Metropolitan Kansas City, MOMissouri | $251.54 | — |
| Metropolitan St. Louis, MOMissouri | $254.48 | — |
| Rest of MissouriMissouri | $234.33 | — |
| MississippiMississippi | $233.79 | — |
| MontanaMontana | $265.20 | — |
| North CarolinaNorth Carolina | $249.75 | — |
| North DakotaNorth Dakota | $264.41 | — |
| NebraskaNebraska | $247.17 | — |
| New HampshireNew Hampshire | $274.20 | — |
| Northern New JerseyNew Jersey | $303.59 | — |
| Rest of New JerseyNew Jersey | $287.51 | — |
| New MexicoNew Mexico | $246.93 | — |
| NevadaNevada | $265.20 | — |
| NYC suburbs and Long Island, NYNew York | $311.17 | — |
| Poughkeepsie and northern NYC suburbs, NYNew York | $288.53 | — |
| Queens, NYNew York | $309.05 | — |
| Rest of New YorkNew York | $253.63 | — |
| OhioOhio | $245.77 | — |
| OklahomaOklahoma | $241.00 | — |
| Portland, OROregon | $290.31 | — |
| Rest of OregonOregon | $263.91 | — |
| Metropolitan Philadelphia, PAPennsylvania | $275.35 | — |
| Rest of PennsylvaniaPennsylvania | $246.81 | — |
| Puerto RicoPuerto Rico | $267.64 | — |
| Rhode IslandRhode Island | $273.20 | — |
| South CarolinaSouth Carolina | $248.02 | — |
| South DakotaSouth Dakota | $264.32 | — |
| TennesseeTennessee | $244.25 | — |
| Austin, TXTexas | $278.09 | — |
| Beaumont, TXTexas | $245.00 | — |
| Brazoria, TXTexas | $263.22 | — |
| Dallas, TXTexas | $264.48 | — |
| Fort Worth, TXTexas | $262.27 | — |
| Galveston, TXTexas | $263.73 | — |
| Houston, TXTexas | $264.46 | — |
| Rest of TexasTexas | $253.68 | — |
| UtahUtah | $251.66 | — |
| VirginiaVirginia | $261.01 | — |
| Virgin Islands, VIUnited States Virgin Islands | $267.64 | — |
| VermontVermont | $262.31 | — |
| Rest of WashingtonWashington | $277.25 | — |
| King County, WAWashington | $317.70 | — |
| WisconsinWisconsin | $254.89 | — |
| West VirginiaWest Virginia | $236.51 | — |
| WyomingWyoming | $264.86 | — |
88366 rates by state
Office rate range in each state. Select a state to see its payment localities.
Explore a state
Local rates. Clear comparisons.
Hover or focus a tile to see its rate range. Select it to open the state’s fee schedule.
$233.05
$327.26
Color shows the midpoint of each state’s locality range.
View every state and territory as a table
| State / territory | Office rate range | Localities |
|---|---|---|
| AK | $299.34 | 1 |
| AL | $236.69 | 1 |
| AR | $233.05 | 1 |
| AZ | $258.08 | 1 |
| CA | $286.72–$367.79 | 29 |
| CO | $279.70 | 1 |
| CT | $283.50 | 1 |
| DC | $307.31 | 1 |
| DE | $262.59 | 1 |
| FL | $256.04–$276.41 | 3 |
| GA | $241.33–$269.17 | 2 |
| GU | $295.25 | 1 |
| HI | $295.25 | 1 |
| IA | $245.40 | 1 |
| ID | $246.62 | 1 |
| IL | $246.52–$272.55 | 4 |
| IN | $248.20 | 1 |
| KS | $243.09 | 1 |
| KY | $240.29 | 1 |
| LA | $239.45–$252.20 | 2 |
| MA | $277.42–$310.06 | 2 |
| MD | $268.18–$307.31 | 3 |
| ME | $246.82–$262.70 | 2 |
| MI | $245.94–$258.30 | 2 |
| MN | $270.74 | 1 |
| MO | $234.33–$254.48 | 3 |
| MS | $233.79 | 1 |
| MT | $265.20 | 1 |
| NC | $249.75 | 1 |
| ND | $264.41 | 1 |
| NE | $247.17 | 1 |
| NH | $274.20 | 1 |
| NJ | $287.51–$303.59 | 2 |
| NM | $246.93 | 1 |
| NV | $265.20 | 1 |
| NY | $253.63–$311.17 | 5 |
| OH | $245.77 | 1 |
| OK | $241.00 | 1 |
| OR | $263.91–$290.31 | 2 |
| PA | $246.81–$275.35 | 2 |
| PR | $267.64 | 1 |
| RI | $273.20 | 1 |
| SC | $248.02 | 1 |
| SD | $264.32 | 1 |
| TN | $244.25 | 1 |
| TX | $245.00–$278.09 | 8 |
| UT | $251.66 | 1 |
| VA | $261.01–$307.31 | 2 |
| VI | $267.64 | 1 |
| VT | $262.31 | 1 |
| WA | $277.25–$317.70 | 2 |
| WI | $254.89 | 1 |
| WV | $236.51 | 1 |
| WY | $264.86 | 1 |
How the 88366 rate is calculated
Each of 88366’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 · 88366
RVUs × geographic indexes × conversion factor
Work1.21
1.21 RVUs× 1.000 GPCI
Practice expense6.69
6.69 RVUs× 1.000 GPCI
Malpractice0.04
0.04 RVUs× 1.000 GPCI
Adjusted RVUs
7.9400
Conversion factor
$33.4009
Medicare rate
$265.20
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
The exact Baltimore area, MD inputs and CMS source lines
PPRRVU2026_Oct_nonQPP.csv
11,291
- Code
- 88366
- Physician work
- 1.21
- Practice expense
- 6.69
- Malpractice
- 0.04
GPCI2026.csv
60
- Locality
- Baltimore area, MD
- Physician work
- 1.016
- Practice expense
- 1.073
- Malpractice
- 1.237
| Component | RVU | Locality factor | Adjusted |
|---|---|---|---|
| Physician work | 1.21 | × 1.016 | 1.2294 |
| Practice expense | 6.69 | × 1.073 | 7.1784 |
| Malpractice | 0.04 | × 1.237 | 0.0495 |
| Total RVUs | 8.4572 | ||
| Conversion factor | × 33.4009 | ||
Office rate, Baltimore area, MD$282.48
Office: (1.21 × 1.016 + 6.69 × 1.073 + 0.04 × 1.237) × $33.4009 = $282.48
Payment rules and modifiers for 88366
The CMS indicators that decide how 88366 is paid alongside other services.
CMS payment indicators · 88366
FISH interpretation, interpretation and report
| Rule | CMS value | What it means |
|---|---|---|
| Global period | XXX | The global surgery concept doesn’t apply. |
| 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
88366 without 26 · national office
$265.20
FISH interpretation, interpretation and report
88366-26 · Professional component
$57.78
Pays only the interpretation and report.
How 88366 has changed in Baltimore area, MD
88366 · Office / nonfacility
$282.48
Effective 2026-10-01
The base rate is $4.08 higher than on 2025-10-01, moving from $278.40 to $282.48 (1.5%).
It is unchanged from the immediately preceding available release, effective 2026-07-01.
One bar per available release, ordered by effective date. Missing rates remain gaps. These comparisons hold the code, setting and locality identifiers constant; they do not isolate which policy or input caused a change.
What changed, release by release
January 1, 2026
RVU26A
$278.40changed to$282.48
- Conversion factor 32.3465 changed to 33.4009
- Work RVU 1.24 changed to 1.21
- Practice expense RVU 6.75 changed to 6.69
- Malpractice RVU 0.05 changed to 0.04
- Work GPCI 1.020 changed to 1.016
- Practice expense GPCI 1.078 changed to 1.073
- Malpractice GPCI 1.309 changed to 1.237
Held through RVU26B, RVU26C, RVU26D.
January 1, 2025
RVU25A
$290.37changed to$278.40
- Conversion factor 33.2875 changed to 32.3465
- Practice expense RVU 6.87 changed to 6.75
- Malpractice RVU 0.04 changed to 0.05
Held through RVU25B, RVU25C, RVU25D.
March 9, 2024
RVU24AR
$285.63changed to$290.37
- Conversion factor 32.7442 changed to 33.2875
Held through RVU24B, RVU24C, RVU24D.
January 1, 2024
RVU24A
$303.76changed to$285.63
- Conversion factor 33.8872 changed to 32.7442
- Practice expense RVU 7.03 changed to 6.87
- Work GPCI 1.024 changed to 1.020
- Practice expense GPCI 1.087 changed to 1.078
- Malpractice GPCI 1.311 changed to 1.309
January 1, 2023
RVU23A
$314.84changed to$303.76
- Conversion factor 34.6062 changed to 33.8872
- Practice expense RVU 7.09 changed to 7.03
- Work GPCI 1.028 changed to 1.024
- Practice expense GPCI 1.096 changed to 1.087
- Malpractice GPCI 1.313 changed to 1.311
Held through RVU23B, RVU23C, RVU23D.
January 1, 2022
RVU22A
$318.98changed to$314.84
- Conversion factor 34.8931 changed to 34.6062
- Practice expense RVU 7.13 changed to 7.09
Held through RVU22B, RVU22C, RVU22D.
January 1, 2021
RVU21A
$305.46changed to$318.98
- Conversion factor 36.0896 changed to 34.8931
- Practice expense RVU 6.52 changed to 7.13
- Work GPCI 1.026 changed to 1.028
- Practice expense GPCI 1.095 changed to 1.096
- Malpractice GPCI 1.304 changed to 1.313
Held through RVU21B, RVU21C, RVU21D.
January 1, 2020
RVU20A
$290.67changed to$305.46
- Conversion factor 36.0391 changed to 36.0896
- Practice expense RVU 6.16 changed to 6.52
- Work GPCI 1.023 changed to 1.026
- Malpractice GPCI 1.295 changed to 1.304
Held through RVU20B, RVU20C, RVU20D.
January 1, 2019
RVU19A
$290.75changed to$290.67
- Conversion factor 35.9996 changed to 36.0391
- Practice expense RVU 6.17 changed to 6.16
Held through RVU19B, RVU19C, RVU19D.
January 1, 2018
RVU18AR1
$282.13changed to$290.75
- Conversion factor 35.8887 changed to 35.9996
- Practice expense RVU 5.97 changed to 6.17
- Practice expense GPCI 1.096 changed to 1.095
- Malpractice GPCI 1.238 changed to 1.295
Held through RVU18B, RVU18C, RVU18D.
January 1, 2017
RVU17A
$285.52changed to$282.13
- Conversion factor 35.8043 changed to 35.8887
- Practice expense RVU 6.07 changed to 5.97
- Practice expense GPCI 1.097 changed to 1.096
- Malpractice GPCI 1.181 changed to 1.238
Held through RVU17B, RVU17C, RVU17D.
January 1, 2016
RVU16A
$254.17changed to$285.52
- Conversion factor 35.9335 changed to 35.8043
- Practice expense RVU 5.27 changed to 6.07
- Malpractice RVU 0.02 changed to 0.04
Held through RVU16B, RVU16C, RVU16D.
July 1, 2015
RVU15C
$160.73changed to$254.17
- Conversion factor 35.7547 changed to 35.9335
- Practice expense RVU 2.92 changed to 5.27
Held through RVU15D.
January 1, 2015
RVU15A
No ratechanged to$160.73
Held through RVU15B.
January 1, 2013
RVU13AR
Earliest loaded release: No rate
Held through RVU13B, RVU13C, RVU13D, RVU14A, RVU14B, RVU14C, RVU14D.
| Effective from | Office | Facility | CMS release |
|---|---|---|---|
| 2026-10-01 | $282.48 | Not available in this setting | RVU26D |
| 2026-07-01 | $282.48 | Not available in this setting | RVU26C |
| 2026-04-01 | $282.48 | Not available in this setting | RVU26B |
| 2026-01-01 | $282.48 | Not available in this setting | RVU26A |
| 2025-10-01 | $278.40 | Not available in this setting | RVU25D |
| 2025-07-01 | $278.40 | Not available in this setting | RVU25C |
| 2025-04-01 | $278.40 | Not available in this setting | RVU25B |
| 2025-01-01 | $278.40 | Not available in this setting | RVU25A |
| 2024-10-01 | $290.37 | Not available in this setting | RVU24D |
| 2024-07-01 | $290.37 | Not available in this setting | RVU24C |
| 2024-04-01 | $290.37 | Not available in this setting | RVU24B |
| 2024-03-09 | $290.37 | Not available in this setting | RVU24AR |
| 2024-01-01 | $285.63 | Not available in this setting | RVU24A |
| 2023-10-01 | $303.76 | Not available in this setting | RVU23D |
| 2023-07-01 | $303.76 | Not available in this setting | RVU23C |
| 2023-04-01 | $303.76 | Not available in this setting | RVU23B |
| 2023-01-01 | $303.76 | Not available in this setting | RVU23A |
| 2022-10-01 | $314.84 | Not available in this setting | RVU22D |
| 2022-07-01 | $314.84 | Not available in this setting | RVU22C |
| 2022-04-01 | $314.84 | Not available in this setting | RVU22B |
| 2022-01-01 | $314.84 | Not available in this setting | RVU22A |
| 2021-10-01 | $318.98 | Not available in this setting | RVU21D |
| 2021-07-01 | $318.98 | Not available in this setting | RVU21C |
| 2021-04-01 | $318.98 | Not available in this setting | RVU21B |
| 2021-01-01 | $318.98 | Not available in this setting | RVU21A |
| 2020-10-01 | $305.46 | Not available in this setting | RVU20D |
| 2020-07-01 | $305.46 | Not available in this setting | RVU20C |
| 2020-04-01 | $305.46 | Not available in this setting | RVU20B |
| 2020-01-01 | $305.46 | Not available in this setting | RVU20A |
| 2019-10-01 | $290.67 | Not available in this setting | RVU19D |
| 2019-07-01 | $290.67 | Not available in this setting | RVU19C |
| 2019-04-01 | $290.67 | Not available in this setting | RVU19B |
| 2019-01-01 | $290.67 | Not available in this setting | RVU19A |
| 2018-10-01 | $290.75 | Not available in this setting | RVU18D |
| 2018-07-01 | $290.75 | Not available in this setting | RVU18C |
| 2018-04-01 | $290.75 | Not available in this setting | RVU18B |
| 2018-01-01 | $290.75 | Not available in this setting | RVU18AR1 |
| 2017-10-01 | $282.13 | Not available in this setting | RVU17D |
| 2017-07-01 | $282.13 | Not available in this setting | RVU17C |
| 2017-04-01 | $282.13 | Not available in this setting | RVU17B |
| 2017-01-01 | $282.13 | Not available in this setting | RVU17A |
| 2016-10-01 | $285.52 | Not available in this setting | RVU16D |
| 2016-07-01 | $285.52 | Not available in this setting | RVU16C |
| 2016-04-01 | $285.52 | Not available in this setting | RVU16B |
| 2016-01-01 | $285.52 | Not available in this setting | RVU16A |
| 2015-10-01 | $254.17 | Not available in this setting | RVU15D |
| 2015-07-01 | $254.17 | Not available in this setting | RVU15C |
| 2015-04-01 | $160.73 | Not available in this setting | RVU15B |
| 2015-01-01 | $160.73 | Not available in this setting | RVU15A |
| 2014-10-01 | Not in this release | Not in this release | RVU14D |
| 2014-07-01 | Not in this release | Not in this release | RVU14C |
| 2014-04-01 | Not in this release | Not in this release | RVU14B |
| 2014-01-01 | Not in this release | Not in this release | RVU14A |
| 2013-10-01 | Not in this release | Not in this release | RVU13D |
| 2013-07-01 | Not in this release | Not in this release | RVU13C |
| 2013-04-01 | Not in this release | Not in this release | RVU13B |
| 2013-01-01 | Not in this release | Not in this release | RVU13AR |
Where the Baltimore area, MD rate applies
Baltimore area, MD is a Medicare payment area, not a city. Our Census mapping connects it to 100 cities and communities in Maryland. Some span more than one payment area; confirm with the service ZIP.
- Baltimore
- Aberdeen
- Aberdeen Proving Ground
- Abingdon
- Annapolis
- Annapolis Neck
- Arbutus
- Arden on the Severn
88366 billing questions
How does 88366 differ from the probe-staining codes?
88366 represents interpretation and reporting of in situ hybridization findings. Codes such as 88364 and 88367 describe probe-staining procedures, including whether the procedure is automated.
Can the professional and technical portions be billed separately?
Yes. Modifier 26 identifies the professional interpretation and modifier TC identifies the technical service. Without either modifier, the claim represents the global service.
What documentation supports 88366?
The record should identify the specimen and in situ hybridization findings and include the diagnostic interpretation and report. The report should make clear the clinical conclusion drawn from the probe results.
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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