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HCC Buddy
Alphabetic Index and Tabular path
HCC Buddy public API, FY2026 Apr updateSource load source requiredSource year 2026Updated 2026-04-01

Index trail

Malignant neoplasm of base of tongue

See Tabular List: C01

C01, Malignant neoplasm of base of tongue

Selected code, source checked for the selected effective period

Commonly confused codes

official source

Not listed for this effective period.

Code details and official notes

C01

Malignant neoplasm of base of tongue

Open the shareable code page for C01→
billableHCC mapped

Includes

official source
  • Malignant neoplasm of dorsal surface of base of tongue
  • Malignant neoplasm of fixed part of tongue NOS
  • Malignant neoplasm of posterior third of tongue

Excludes 1

official source

No Excludes 1 note is listed in this source payload.

Excludes 2

official source

No Excludes 2 note is listed in this source payload.

Code First

official source

Not listed for this effective period.

Use Additional

official source
  • code to identify:
  • alcohol abuse and dependence (F10.-)
  • history of tobacco dependence (Z87.891)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

Code Also

official source

Not listed for this effective period.

7th character

official source

Not listed for this code in the selected Tabular payload.

Placeholder X

official source

Not listed for this code in the selected Tabular payload.

Laterality

official source

No laterality instruction is listed for this code in the selected Tabular payload.

Effective period

source required
  • FY2026 Apr update
  • Source year 2026
  • Updated 2026-04-01
  • HCC Buddy public API
HCC Buddy
HCC Buddy
Alphabetic Index and Tabular path
HCC Buddy public API, FY2026 Apr updateSource load source requiredSource year 2026Updated 2026-04-01

Index trail

Malignant neoplasm of base of tongue

See Tabular List: C01

C01, Malignant neoplasm of base of tongue

Selected code, source checked for the selected effective period

Commonly confused codes

official source

Not listed for this effective period.

Code details and official notes

C01

Malignant neoplasm of base of tongue

Open the shareable code page for C01→
billableHCC mapped

Includes

official source
  • Malignant neoplasm of dorsal surface of base of tongue
  • Malignant neoplasm of fixed part of tongue NOS
  • Malignant neoplasm of posterior third of tongue

Excludes 1

official source

No Excludes 1 note is listed in this source payload.

Excludes 2

official source

No Excludes 2 note is listed in this source payload.

Code First

official source

Not listed for this effective period.

Use Additional

official source
  • code to identify:
  • alcohol abuse and dependence (F10.-)
  • history of tobacco dependence (Z87.891)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

Code Also

official source

Not listed for this effective period.

7th character

official source

Not listed for this code in the selected Tabular payload.

Placeholder X

official source

Not listed for this code in the selected Tabular payload.

Laterality

official source

No laterality instruction is listed for this code in the selected Tabular payload.

Effective period

source required
  • FY2026 Apr update
  • Source year 2026
  • Updated 2026-04-01
  • HCC Buddy public API
HCC Buddy Insights

HCC Mapping

HCC 21 Lymphoma and Other Cancers (V28)HCC 11 Colorectal, Bladder, and Other Cancers (V24)HCC 22 Cancer, Other Specified Sites (RxHCC)HCC 11 Colorectal, Bladder, and Other Cancers (ESRD/PACE)HCC 11 HHS-HCC 11; HHS-HCC 2026 benefit year (HHS-HCC)

RAF Value

V28: RAF: 0.671V24: RAF: 0.307RxHCC: RAF: 0.124ESRD/PACE: RAF: 0.059HHS-HCC: RAF: Varies by metal level

Model Period

FY2026 Apr update

Source

source required

Audit Caution

Close codes need documentation support before selection. Do not assume relationships.
Reviewed by the HCC Buddy Coding Team

HCC Buddy workflow band

HCC mapping, RAF, MEAT, source trail, and audit caution stay in view.

MEAT supportaudit cautionsource required

V28

HCC 21

Lymphoma and Other Cancers

RAF: 0.671

V24

HCC 11

Colorectal, Bladder, and Other Cancers

RAF: 0.307

RxHCC

RxHCC 22

Cancer, Other Specified Sites

RAF: 0.124

ESRD/PACE

HCC 11

Colorectal, Bladder, and Other Cancers

RAF: 0.059

HHS-HCC

HCC 11

HHS-HCC 11; HHS-HCC 2026 benefit year

RAF: Varies by metal level

MEAT checklist

Reviewed by the HCC Buddy Coding Team

Monitor, Evaluate, Assess, or Treat must be supported in the provider note.

HCC Buddy guidance, not official ICD-10-CM text.

Audit caution

Reviewed by the HCC Buddy Coding Team

Close codes need documentation support before selection. Do not assume relationships.

HCC Buddy guidance, not official ICD-10-CM text.

Reviewer sign-off

Reviewed by the HCC Buddy Coding Team

MEAT, documentation support, audit cautions, and close-code guidance are reviewed and approved for this effective period.

HCC Buddy enrichment is separate from official source text.

Last updated: April 1, 2026 · Not a substitute for official coding guidelines. No PHI or patient data.
HCC Buddy Code Card
FY 2026 Apr update
C01Billable

Malignant neoplasm of base of tongue

CMS-HCC V28

HCC 21

RAF 0.671

CMS-HCC V24

HCC 11

RAF 0.307

RxHCC

RxHCC 22

RAF 0.124

Reviewed by the HCC Buddy Coding TeamFY2026 Apr update

Code

C01

V28 HCC

HCC 21

RAF

0.671

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