Outcomes of first-line treatment for chronic lymphocytic leukemia with 17p deletion

Abstract

Although uncommon in treatment-naive patients with chronic lymphocytic leukemia, deletion 17p is a high-risk disease characteristic. We analyzed and reported outcomes for 63 patients with deletion 17p chronic lymphocytic leukemia who received first-line therapy at our institution; at time of first treatment, 81% had unmutated immunoglobulin heavy chain variable gene and 58% had complex karyotype. Forty-nine patients (76%) received first-line fludarabine, cyclophosphamide, rituximab-based therapy, 6 (11%) received rituximab-based and 8 (13%) received lenalidomide-based treatment. Overall, the complete plus nodular partial remission rate was 33%; on multivariable model, higher complete plus nodular partial remission rate was observed in patients with less than 50% cells positive for deletion 17p, and a higher probability of achieving at least a partial remission was observed with fludarabine, cyclophosphamide, rituximab-based treatment. After a median follow up of 33 months (range 1-89 months), the estimated median progression-free survival was 14 months (95% confidence interval 10-18) and estimated median overall survival was 63 months (95% confidence interval 43-83). In multivariable analysis, factors independently associated with longer progression-free survival were response to treatment and absence of complex karyotype. Achievement of complete plus nodular partial remission rate and mutated immunoglobulin heavy chain variable gene were independently associated with longer overall survival in multivariable model. Complex karyotype was associated with increased risk for Richter's transformation. New first-line strategies and agents must aim at both improving response and maintaining remission in patients with deletion 17p, particularly in the presence of complex karyotype.

Figure 1.

Factor associated with longer PFS. (A) Median PFS was longer for patients with non-complex cytogenetic (20 vs. 13 months; P=0.02); there were 26 events among 29 patients with complex cytogenetic; there were 13 events among 25 patients with non-complex karyotype. (B) Median PFS was longer for patients achieving a PR (16 vs. 3 months; P=0.05); there were 13 events among 18 patients achieving a PR; there were 21 events among 24 patients not responding to therapy. (C) Median PFS was longer for patients achieving CR/nPR (37 vs. 8 months; P<0.001); there were 9 events among 21 patients achieving CR/nPR; there were 34 events among 42 patients not achieving CR/nPR.

Figure 2.

Factor associated with longer OS. (A) Median OS was longer for patients with mutated IGHV (not reached vs. 52 months; P=0.05); there were 2 deaths among 11 patients with mutated IGHV; there were 24 deaths among 47 patients with unmutated IGHV. (B) Median OS was longer for patients achieving CR/nPR (not reached vs. 32 months; P=0.001); there were 4 deaths among 21 patients achieving a CR/nPR with initial therapy; there were 24 deaths among 42 patients not achieving a CR/nPR with initial therapy.