Differentiating Chronic Lymphocytic Leukemia from Small Lymphocytic Lymphoma: A Manitoba Cancer Registry Perspective

Monoclonal B-cell lymphocytosis (MBL) does not have a World Health Organization (WHO) International Classification of Diseases for Oncology (ICD-O) morphology code as it is not currently recognized as a reportable disease. Although MBL is premalignant, patients diagnosed with MBL need to be monitored as they eventually progress to chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Working together, the Manitoba CLL Disease Site Group (DSG) and the Manitoba Cancer Registry developed a way to record and track these patients to ensure they receive the proper follow-up care.