Small Lymphocytic Lymphoma with Unmutated Immunoglobulin Heavy Chain Variable-Region Gene

**Semantic type:** Neoplastic Process

**Definition:** Small lymphocytic lymphoma 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:** - Pregerminal Center Small Lymphocytic Lymphoma - SLL with Unmutated IGVH