Treatment Outcomes in Patients (Pts) with Transformed Chronic Lymphocytic Leukemia (CLL) in One Institution.

CLL is usually an indolent lymphoproliferative disease; however pts are at risk over time (3-5% yr) of transformation to a more aggressive histology, e.g., prolymphocytic leukemia (PLL), or Richter’s transformation (RT). The outcome of these pts is poor with median overall responses of 5–43%, CR 5–43%, and overall survival of 5–8 months regardless of the chemotherapeutic approach.

We report on 15 pts with CLL transformed to PLL or RT treated at our institution over the last 4 years. The median pt age at transformation was 64 (51–79). 9 had PLL, 4 had RT, one had an anaplastic histology, and another with atypical transformation. 7/14 pts were positive for ZAP-70 expression. 10/14 presented with CLL prior to the transformation with a median time of 7 yrs (range 3–27), and had undergone prior therapy with either fludarabine or chlorambucil. Pts were treated with mainly rituximab chemotherapy combinations. One pt who achieved a CR, was consolidated with a matched related donor transplantation and remains disease free for 3 yrs.

Conclusion. CR and ORR were higher than reported in the literature. Also, pts treated with rituximab-based combinations achieved longer overall survivals. Rituximab based-combinations should be considered in treating such pts. Whether they would benefit from consolidation therapy needs further investigation.