Predictors of survival in patients with transformed chronic lymphocytic leukemia (TC)

7098 Background: Patients with CLL that develop Richter’s syndrome (RS) have a very poor prognosis. Similarly, pts with CLL that have clinical and histological features (increased large cells/prolymphocytes in CLL tissue biopsy) of increased aggressiveness (defined as accelerated phase CLL, AP) have a poor prognosis. In order to identify prognostic factors in pts with AP and RS, collectively referred to as TC, we reviewed our center experience. Methods: Pts with TC and complete evaluation including biopsy and concomitant FDG/PET were included. Pts with de novo TC were excluded as their prognosis is substantially superior versus previously treated pts. Pts with N+ or M+ concurrent solid tumors were also excluded. Since FDG/PET-derived SUV reflects tumor proliferative rate, we used SUVmax≥10 to indicate high-risk disease (Falchi, Blood. 2012;120: abstr # 927). We identified factors associated with outcome and performed a multivariable model for OS. Results: One hundred eighty-three consecutive pts with TC (99 with AP and 84 with RS) were evaluated at MDACC between 2002 and 2012. Demographic and clinical characteristics were similar between pts with AP and pts with RS. 30% and 77% of pts with AP and RS, respectively had an SUVmax≥10. Approximately half of the pts were treated with intensive chemoimmunotherapy after the TC diagnosis. CR rates were 21% and 16% and overall response rates were 37% and 26% for pts with AP and RS, respectively. At the time of this analysis 144/183 pts have died, for a median OS of 9.6 months (7.9-14.7). Age ≥65, B symptoms, LDH, β2-microglobulin, del17p, SUVmax≥10, extensive disease by FDG/PET (SUVmax≥5 on both sides of the diaphragm), PS≥2 bulky disease and high Ki67 correlated with shorter OS. In multivariable analysis SUV uptake (max≥10), PS higher than 1 and bulky nodal disease (>5 cm) retained independent significance. Conclusions: Based on our experience, an SUVmax of 10 or higher, PS higher than 1 and bulky nodal disease (>5 cm) are the most important factors predicting outcome in pts with TC. A prognostic model for survival is being developed for pts with TC.