ICD-10 Code C91.60 – Prolymphocytic leukemia of T-cell type not having achieved remission (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C91.60 – Prolymphocytic leukemia of T-cell type not having achieved remission
What it is
C91.60 identifies T-cell prolymphocytic leukemia that has not yet reached remission. Use it for this specific hematologic malignancy when the record states the disease is active or persistent.
Clinical signs
Clinical features vary; refer to documentation. Common references describe an aggressive mature T-cell leukemia with abnormal lymphocytosis, enlarged spleen, and possible lymph node or skin involvement.
When to use this code
Use C91.60 when the clinician documents T-cell prolymphocytic leukemia and states remission has not been achieved. It also fits ongoing active disease during evaluation, follow-up, or treatment planning when remission is not documented. If the chart does not clearly specify T-cell type or remission status, check documentation.
Do not use for
Do not use this code for B-cell prolymphocytic leukemia, other lymphoid leukemias, or cases documented as in remission. If the type or disease status is unclear, check documentation.
Coding tip
Code only when both T-cell type and “not having achieved remission” are explicitly supported in the record.