What is ICD-10 code C91.32?

C91.32 is the ICD-10-CM diagnosis code for Prolymphocytic leukemia of B-cell type, in relapse. A rare blood cancer (prolymphocytic leukemia) affecting B-cells that has returned after a period of remission. It belongs to the ICD-10-CM chapter for neoplasms (c00-d49). C91.32 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. C91.32 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. C91.32 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. C91.32 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

What is the V28 vs V24 difference for C91.32?

CMS phased in the V28 risk adjustment model over payment years 2024 (33%), 2025 (67%), and 2026 (100%), replacing V24. V28 consolidates HCC categories, removes some lower-acuity conditions, and recalibrates RAF weights across the entire model. For C91.32, V28 maps to Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers at RAF 1.798 while V24 mapped to Lymphoma and Other Cancers at RAF 0.675. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting C91.32?

The fifth character '2' indicates relapse - document that cancer has recurred after previous remission Distinguish between initial diagnosis and relapse status in medical record review Because C91.32 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score.

2026 ICD-10-CM C91.32: Prolymphocytic leukemia

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupC91.32Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Neoplasms (C00-D49) / Malignant neoplasms of lymphoid, hematopoietic and related tissue (C81-C96)

C91.32

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Prolymphocytic leukemia of B-cell type, in relapse

A rare blood cancer (prolymphocytic leukemia) affecting B-cells that has returned after a period of remission.

Buddy Insight

Prolymphocytic leukemia of B-cell type in relapse indicates recurrence of this rare aggressive leukemia after a prior period of remission.

CMS-HCC V28

Mapped

HCC 19

Myelodysplastic Syndromes, Mu...

RAF 1.798

CMS-HCC V24

Mapped

HCC 10

Lymphoma and Other Cancers

RAF 0.675

ACA/HHS

Mapped

HCC 10

HHS-HCC 10

Varies by metal level

ESRD/PACE

Mapped

HCC 10

Lymphoma and Other Cancers

RAF 0.111

RXHCC

Mapped

HCC 19

Lymphoma and Other Cancers

RAF 1.949

Code Book Path

Official

C91Lymphoid leukemia

C91.3Prolymphocytic leukemia of B-cell type

C91.32Prolymphocytic leukemia of B-cell type, in relapse

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for C91.32 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for C91.32 in this effective period.

Related Child Codes

Official

C91.30Prolymphocytic leukemia of B-cell type not having achieved remission

C91.31Prolymphocytic leukemia of B-cell type, in remission

Includes

Official

ICD-10-CM does not list Includes notes for C91.32 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for C91.32 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for C91.32 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for C91.32 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for C91.32 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Documentation must confirm prior remission followed by disease recurrence with evidence of prolymphocytic cells in blood or bone marrow.

The interval between remission and relapse, prior treatment regimens, and current disease burden should be documented.

Updated molecular and cytogenetic testing at relapse may reveal new clonal evolution relevant to treatment decisions.

MEAT Support

HCC Buddy guidance

Documentation must confirm prior remission followed by disease recurrence with evidence of prolymphocytic cells in blood or bone marrow.

The interval between remission and relapse, prior treatment regimens, and current disease burden should be documented.

Updated molecular and cytogenetic testing at relapse may reveal new clonal evolution relevant to treatment decisions.

Audit Caution

HCC Buddy guidance

Relapse requires documentation of prior remission followed by recurrence -

do not use for refractory disease that never responded to treatment. The distinction between relapse and primary refractory B-PLL impacts treatment decisions and should be accurately reflected in coding. Ensure the pathology at relapse still shows prolymphocytic morphology rather than transformation to another entity.

Common Mistakes

HCC Buddy guidance

C91.30 (B-PLL not in remission) is for active disease without prior remission.

C91.31 (B-PLL in remission) is used when disease is controlled.

C91.12 (B-CLL in relapse) should not be used for relapsed B-PLL.

C91.Z2 (other lymphoid leukemia in relapse) is less specific and should not be used when B-PLL is confirmed.

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is C91.32 an HCC code?

Yes. C91.32 (Prolymphocytic leukemia of B-cell type, in relapse) maps to Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers under the CMS-HCC V28 risk adjustment model (and Lymphoma and Other Cancers under V24), with a community non-dual aged RAF of 1.798. It is billable for payment year 2026.

Coder answer: C91.32 is billable and maps to V28 HCC 19, Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers. Open it in the Code Book for the tabular path, RAF, and MEAT checklist.

Code: C91.32
Description: Prolymphocytic leukemia of B-cell type, in relapse
HCC (V28): HCC 19 — Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers
RAF: 1.798
Billable: Yes
Payment year: 2026

HCC Category Mapping

V28HCC 19, Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers

1.798

V24HCC 10, Lymphoma and Other Cancers

0.675

ESRDHCC 10, Lymphoma and Other Cancers

0.111

RxHCCHCC 19, Lymphoma and Other Cancers

1.949

Each model's RAF is its CMS base weight for that model's standard population, so weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

Work C91.32 in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for C91.32

For C91.32 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed C91.32 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

Get the V28 RAF + MEAT cheat sheet

One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.

Free PDF. No card. Unsubscribe anytime.

What This Code Means

C91.32 is the ICD-10-CM diagnosis code for prolymphocytic leukemia of b-cell type, in relapse. A rare blood cancer (prolymphocytic leukemia) affecting B-cells that has returned after a period of remission. C91.32 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of lymphoid, hematopoietic and related tissue (c81-c96).

Under the CMS-HCC V28 risk adjustment model, C91.32 maps to Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers (HCC 19) with a community, non-dual, aged base RAF weight of 1.798. Under the older CMS-HCC V24 model, C91.32 maps to Lymphoma and Other Cancers (HCC 10) with a community, non-dual, aged base RAF weight of 0.675. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.

The fifth character '2' indicates relapse - document that cancer has recurred after previous remission. Because C91.32 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for C91.32 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•The fifth character '2' indicates relapse - document that cancer has recurred after previous remission
•Distinguish between initial diagnosis and relapse status in medical record review

Clinical Significance

Prolymphocytic leukemia of B-cell type in relapse indicates recurrence of this rare aggressive leukemia after a prior period of remission. Relapsed B-PLL carries a particularly poor prognosis and often requires salvage chemotherapy, targeted agents, or consideration for allogeneic stem cell transplantation. The disease frequently becomes more treatment-resistant with each subsequent relapse.

Documentation Requirements

✓Documentation must confirm prior remission followed by disease recurrence with evidence of prolymphocytic cells in blood or bone marrow.
✓The interval between remission and relapse, prior treatment regimens, and current disease burden should be documented.
✓Updated molecular and cytogenetic testing at relapse may reveal new clonal evolution relevant to treatment decisions.

Commonly Confused Codes

•C91.30 (B-PLL not in remission) is for active disease without prior remission.
•C91.31 (B-PLL in remission) is used when disease is controlled.
•C91.12 (B-CLL in relapse) should not be used for relapsed B-PLL.
•C91.Z2 (other lymphoid leukemia in relapse) is less specific and should not be used when B-PLL is confirmed.