ICD-10 Code C91.91 – Lymphoid leukemia, unspecified, in remission (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C91.91 – Lymphoid leukemia, unspecified, in remission
What it is
This code identifies a history of lymphoid leukemia that is currently in remission, but the specific subtype is not documented. Use it when the record confirms remission and does not name a more precise lymphoid leukemia.
Clinical signs
Clinical features vary; refer to documentation. In remission, the chart usually shows no active leukemia findings, and the diagnosis is based on the provider’s statement rather than current symptoms alone.
When to use this code
Use this code when the provider documents unspecified lymphoid leukemia as being in remission, such as during follow-up, surveillance, or survivorship visits. It also fits when the exact lymphoid leukemia type is not stated in the note. If the record identifies a specific subtype, code that diagnosis instead.
Do not use for
Do not use this code for active leukemia, relapse, or treatment complications. Do not assign it when the subtype is documented and a more specific code is available.
Coding tip
Confirm both “lymphoid leukemia” and “in remission” in the provider documentation before assigning C91.91.