Chronic lymphocytic leukemia with paraimmunoblastic transformation - with comparative genomic hybridization and review of the literature.

Richter's transformation (RT) is the development of a high-grade lymphoma in patients with B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). We report an extremely rare case with paraimmunoblastic transformation. A 78-year-old Taiwanese male had Rai stage 1 and Binet stage B CLL/SLL involving skin, peripheral blood (PB), and bone marrow (BM) with paraimmunoblastic transformation in the lymph node. Molecular/genomic studies showed the same clonal origin of tumor tissues at various locations with trisomy 12 and a deletion of chromosome 13q14. Interestingly, there seemed to be no additional chromosomal aberrations in the transformed nodal tissue, suggesting that the micro-environment rather than an additional genetic lesion contributed to the transformation. The patient received chemotherapy and was alive with disease after 33.5 months.