Telomere shortening, TP53 mutations and deletions in chronic lymphocytic leukemia result in increased chromosomal instability and breakpoint clustering in heterochromatic regions.

Complex karyotypes are associated with a poor prognosis in chronic lymphocytic leukemia (CLL). Using mFISH, iFISH, and T/C-FISH, we thoroughly characterized 59 CLL patients regarding parameters known to be involved in chromosomal instability: status of the genes ATM and TP53 and telomere length. Interestingly, a deletion of the ATM locus in 11q, independent of the cytogenetic context, was associated with significantly diminished risk (p<0.05) of carrying a mutation in TP53. In patients with loss or mutation of TP53, chromosomal breakage occurred more frequently (p<0.01) in (near-) heterochromatic regions. Median telomere length in patients with complex karyotypes was significantly shorter than that of healthy controls and shorter than in all other cytogenetic cohorts. Furthermore, the median telomere length of patients carrying a TP53 mutation was significantly shorter than without mutation. We conclude that telomere shortening in combination with loss of TP53 induces increased chromosomal instability with preferential involvement of (near-) heterochromatic regions.

Randomised phase II trial of trofosfamide vs. doxorubicin in elderly patients with untreated metastatic soft-tissue sarcoma.

Doxorubicin represents the standard first-line treatment for metastatic soft-tissue sarcoma. We assessed the efficacy and safety of trofosfamide in elderly patients. In this controlled phase II trial, we randomly (1:2) assigned 120 previously untreated patients with soft-tissue sarcoma, older than 60 years, with an Eastern Cooperative Oncology Group score of 0-2, to receive either doxorubicin for 6 cycles (arm A) or oral trofosfamide (arm B). The primary end-point was a 6-month progression-free rate (PFR) in the experimental arm (clinical trial information: NCT00204568). Between August 2004 and October 2012, forty and 80 patients were randomly assigned to arm A and arm B, respectively, in 16 centres. The median age was 70 years (range, 60-89). The primary study end-point (6-month PFR) was exceeded, with 27.6% in arm B (95% confidence interval [CI], 18.0-39.1) and 35.9% in arm A: (95% CI, 21.2-52.8). Survival data in terms of progression-free survival were 4.3 months (95% CI, 2.2-6.3) and 2.8 months (95% CI, 1.7-3.6) and in terms of overall survival were 9.8 months (95% CI, 6.7-11.6) and 12.3 months (95% CI, 9.6-16.2), respectively. The number of serious adverse event (SAE) was 59% in arm A and 30.3% in arm B (p = 0.005). Trofosfamide caused more often dyspnoea and low-grade fatigue, whereas with doxorubicin, more often leukocytopenia, neutropenia and mucositis were seen. Discontinuation rates for reasons other than disease progression were 15.4% (arm A) vs. 7.9% (arm B). In an elderly population of patients, oral trofosfamide achieved the estimated primary end-point 6-month PFR and was associated with a favourable toxicity profile compared with doxorubicin.