Chronic Lymphocytic Leukemia with Unmutated Immunoglobulin Heavy Chain Variable-Region Gene

**Semantic type:** Neoplastic Process

**Definition:** Chronic lymphocytic leukemia characterized by the absence of somatic hypermutation within the immunoglobulin heavy chain gene variable region of neoplastic clones. Patients have a significantly worse prognosis as compared to those with mutated immunoglobulin heavy chain gene variable region rearrangements.

**Synonyms:** - CLL with Unmutated IGVH - Pregerminal Center Chronic Lymphocytic Leukemia