2026 ICD-10-CM Diagnosis Code C91.A1Mature B-cell leukemia Burkitt-type, in remission

ICD-10-CM Codes›C00–D49›C81-C96›C91

ICD-10-CM C91.A1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C91.A1 is a billable ICD-10-CM diagnosis code for mature B-cell leukemia Burkitt-type, in remission. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 820 through 825, 840 through 842. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Leukemia in remission.

Code Identity

ICD-10-CM Code
C91.A1
Billable Status
Yes — Valid for Submission
Code Describes
Mature B-cell leukemia Burkitt-type, in remission
Short Description
Mature B-cell leukemia Burkitt-type, in remission
Same as the full description in the CMS dataset.
Parent Code
C91.A
Mature B-cell leukemia Burkitt-type

Code Classification

ChapterC00–D49Neoplasms
SectionC81-C96Malignant neoplasms of lymphoid, hematopoietic and related tissue
CategoryC91Lymphoid leukemia
This CodeC91.A1Mature B-cell leukemia Burkitt-type, in remission

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO075
Leukemia in remission
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Lymphoma

Lymphoma is a cancer of a part of the immune system called the lymph system. There are many types of lymphoma. One type is Hodgkin disease. The rest are called non-Hodgkin lymphomas.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert C91.A1 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
204.81 Oth lym leuk w rmsion
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About C91.A1Overview

Is C91.A1 (Mature B-cell leukemia Burkitt-type) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report mature B-cell leukemia Burkitt-type, in remission on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C91.A1 group to?

When mature B-cell leukemia Burkitt-type, in remission is the principal diagnosis on an inpatient stay, it groups to MS-DRG 820, 821, 822, 823, 824, 825, 840, 841, 842, with relative weights from 1.0104 to 5.8648 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of C91.A1?

Under the General Equivalence Mappings, mature B-cell leukemia Burkitt-type, in remission converts to ICD-9-CM 204.81 (oth lym leuk w rmsion). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.