ICD-10 Code C91.30 – Prolymphocytic leukemia of B-cell type not having achieved remission (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C91.30 – Prolymphocytic leukemia of B-cell type not having achieved remission
What it is
C91.30 identifies B-cell prolymphocytic leukemia that has not yet reached remission. Use it when the record clearly states this leukemia subtype and ongoing active disease.
Clinical signs
Clinical features vary; refer to documentation. Typical references describe an aggressive mature B-cell leukemia with circulating abnormal lymphoid cells, lymphocytosis, splenomegaly, and possible anemia or thrombocytopenia.
When to use this code
Use C91.30 when the provider documents B-cell prolymphocytic leukemia and states the patient is not in remission. It fits active disease during evaluation, treatment planning, or follow-up when remission has not been achieved.
Code from the exact wording in the note, pathology report, or oncology assessment. If the type, remission status, or even the diagnosis is unclear, check documentation before assigning the code.
Do not use for
Do not use this code for T-cell prolymphocytic leukemia, other lymphoid leukemias, or a history of leukemia in remission. Check documentation if the record only says “leukemia” without subtype.
Coding tip
Confirm both the B-cell subtype and the “not having achieved remission” status before coding; missing either detail can change the code selection.