Manuela Bergmann

TP53 Mutation and Survival in Chronic Lymphocytic Leukemia

PURPOSE The precise prognostic impact of TP53 mutation and its incorporation into treatment algorithms in chronic lymphocytic leukemia (CLL) is unclear. We set out to define the impact of TP53 mutations in CLL. PATIENTS AND METHODS We assessed TP53 mutations by denaturing high-performance liquid chromatography (exons 2 to 11) in a randomized prospective trial (n = 375) with a follow-up of 52.8 months (German CLL Study Group CLL4 trial; fludarabine [F] v F + cyclophosphamide [FC]). RESULTS We found TP53 mutations in 8.5% of patients (28 of 328 patients). None of the patients with TP53 mutation showed a complete response. In patients with TP53 mutation, compared with patients without TP53 mutation, median progression-free survival (PFS; 23.3 v 62.2 months, respectively) and overall survival (OS; 29.2 v 84.6 months, respectively) were significantly decreased (both P < .001). TP53 mutations in the absence of 17p deletions were found in 4.5% of patients. PFS and OS for patients with 17p deletion and patients with TP53 mutation in the absence of 17p deletion were similar. Multivariate analysis identified TP53 mutation as the strongest prognostic marker regarding PFS (hazard ratio [HR] = 3.8; P < .001) and OS (HR = 7.2; P < .001). Other independent predictors of OS were IGHV mutation status (HR = 1.9), 11q deletion (HR = 1.9), 17p deletion (HR = 2.3), and FC treatment arm (HR = 0.6). CONCLUSION CLL with TP53 mutation carries a poor prognosis regardless of the presence of 17p deletion when treated with F-based chemotherapy. Thus, TP53 mutation analysis should be incorporated into the evaluation of patients with CLL before treatment initiation. Patients with TP53 mutation should be considered for alternative treatment approaches.

Gene mutations and treatment outcome in chronic lymphocytic leukemia: results from the CLL8 trial

Mutations in TP53, NOTCH1, and SF3B1 were analyzed in the CLL8 study evaluating first-line therapy with fludarabine and cyclophosphamide (FC) or FC with rituximab (FCR) among patients with untreated chronic lymphocytic leukemia (CLL). TP53, NOTCH1, and SF3B1 were mutated in 11.5%, 10.0%, and 18.4% of patients, respectively. NOTCH1(mut) and SF3B1(mut) virtually showed mutual exclusivity (0.6% concurrence), but TP53(mut) was frequently found in NOTCH1(mut) (16.1%) and in SF3B1(mut) (14.0%) patients. There were few significant associations with clinical and laboratory characteristics, but genetic markers had a strong influence on response and survival. In multivariable analyses, an independent prognostic impact was found for FCR, thymidine kinase (TK) ≥10 U/L, unmutated IGHV, 11q deletion, 17p deletion, TP53(mut), and SF3B1(mut) on progression-free survival; and for FCR, age ≥65 years, Eastern Cooperative Oncology Group performance status ≥1, β2-microglobulin ≥3.5 mg/L, TK ≥10 U/L, unmutated IGHV, 17p deletion, and TP53(mut) on overall survival. Notably, predictive marker analysis identified an interaction of NOTCH1 mutational status and treatment in that rituximab failed to improve response and survival in patients with NOTCH1(mut). In conclusion, TP53 and SF3B1 mutations appear among the strongest prognostic markers in CLL patients receiving current-standard first-line therapy. NOTCH1(mut) was identified as a predictive marker for decreased benefit from the addition of rituximab to FC. This study is registered at www.clinicaltrials.gov as #NCT00281918.

Development of a comprehensive prognostic index for patients with chronic lymphocytic leukemia

In addition to clinical staging, a number of biomarkers predicting overall survival (OS) have been identified in chronic lymphocytic leukemia (CLL). The multiplicity of markers, limited information on their independent prognostic value, and a lack of understanding of how to interpret discordant markers are major barriers to use in routine clinical practice. We therefore performed an analysis of 23 prognostic markers based on prospectively collected data from 1948 CLL patients participating in phase 3 trials of the German CLL Study Group to develop a comprehensive prognostic index. A multivariable Cox regression model identified 8 independent predictors of OS: sex, age, ECOG status, del(17p), del(11q), IGHV mutation status, serum β2-microglobulin, and serum thymidine kinase. Using a weighted grading system, a prognostic index was derived that separated 4 risk categories with 5-year OS ranging from 18.7% to 95.2% and having a C-statistic of 0.75. The index stratified OS within all analyzed subgroups, including all Rai/Binet stages. The validity of the index was externally confirmed in a series of 676 newly diagnosed CLL patients from Mayo Clinic. Using this multistep process including external validation, we developed a comprehensive prognostic index with high discriminatory power and prognostic significance on the individual patient level. The studies were registered as follows: CLL1 trial (NCT00262782, http://clinicaltrials.gov), CLL4 trial (ISRCTN 75653261, http://www.controlled-trials.com), and CLL8 trial (NCT00281918, http://clinicaltrials.gov).

Interactions between comorbidity and treatment of chronic lymphocytic leukemia: results of German Chronic Lymphocytic Leukemia Study Group trials.

This study investigated the impact of comorbidity in 555 patients with chronic lymphocytic leukemia enrolled in two trials of the German Chronic Lymphocytic Leukemia Study Group on first-line treatment with fludarabine plus cyclophosphamide, fludarabine, or chlorambucil. Patients with two or more comorbidities and patients with less than two comorbidities differed in overall survival (71.7 versus 90.2 months; P<0.001) and progression-free survival (21.0 versus 31.5 months; P<0.01). After adjustment for other prognostic factors and treatment, comorbidity maintained its independent prognostic value in a multivariate Cox regression analysis. Chronic lymphocytic leukemia was the major cause of death in patients with two or more comorbidities. Disease control in patients with two or more comorbidities was better with fludarabine plus cyclophosphamide than with fludarabine treatment, but not with fludarabine compared to chlorambucil treatment. These results give insight into interactions between comorbidity and therapy of chronic lymphocytic leukemia and suggest that durable control of the hematologic disease is most critical to improve overall outcome of patients with increased comorbidity. The registration numbers of the trials reported are NCT00276848 and NCT00262795.

Poor efficacy and tolerability of R-CHOP in relapsed/refractory chronic lymphocytic leukemia and Richter transformation

This phase II trial evaluated efficacy and tolerability of R‐CHOP for up to 8 courses in Richter transformation (RT) and up to 6 courses in CLL plus autoimmune cytopenia (AIC) or high‐risk (HR) features. HR was defined as fludarabine‐refractoriness or early relapse (<36 months) after fludarabine‐based treatment; 26 patients were included as HR, 19 patients had AIC, and 15 patients had RT. In the HR cohort, overall response rate was 54%, progression‐free and overall survival were 9 and 21 months. In AIC patients overall response rate was 74%, progression‐free and overall‐survival were 10 and 41 months, respectively, and median increase in hemoglobin was 3.4 g/L. RT patients responded in 67%, progression‐free was 10 and overall survival 21 months. The most common adverse events were hematologic toxicities in 92%. Severe infections occurred in 28%. Treatment was discontinued early in 45% of all patients mainly as a result of toxicity. This trial shows that R‐CHOP has no role in treating complicated CLL. R‐CHOP is associated with significant toxicities and fairly low efficacy compared with almost every other CLL‐regimen. In RT, it might still be used as an induction therapy before allogeneic stem cell transplantation. Am. J. Hematol. 89:E239–E243, 2014.

Limited clinical relevance of imaging techniques in the follow-up of patients with advanced chronic lymphocytic leukemia: results of a meta-analysis

The clinical value of imaging is well established for the follow-up of many lymphoid malignancies but not for chronic lymphocytic leukemia (CLL). A meta-analysis was performed with the dataset of 3 German CLL Study Group phase 3 trials (CLL4, CLL5, and CLL8) that included 1372 patients receiving first-line therapy for CLL. Response as well as progression during follow-up was reassessed according to the National Cancer Institute Working Group1996 criteria. A total of 481 events were counted as progressive disease during treatment or follow-up. Of these, 372 progressions (77%) were detected by clinical symptoms or blood counts. Computed tomography (CT) scans or ultrasound were relevant in 44 and 29 cases (9% and 6%), respectively. The decision for relapse treatment was determined by CT scan or ultrasound results in only 2 of 176 patients (1%). CT scan results had an impact on the prognosis of patients in complete remission only after the administration of conventional chemotherapy but not after chemoimmunotherapy. In conclusion, physical examination and blood count remain the methods of choice for staging and clinical follow-up of patients with CLL as recommended by the International Workshop on Chronic Lymphocytic Leukemia 2008 guidelines. These trials are registered at http://www.isrctn.org as ISRCTN 75653261 and ISRCTN 36294212 and at http://www.clinicaltrials.gov as NCT00281918.

Progranulin Is a Novel Independent Predictor of Disease Progression and Overall Survival in Chronic Lymphocytic Leukemia

Progranulin (Pgrn) is a 88 kDa secreted protein with pleiotropic functions including regulation of cell cycle progression, cell motility, wound repair and tumorigenesis. Using microarray based gene expression profiling we have recently demonstrated that the gene for Pgrn, granulin (GRN), is significantly higher expressed in aggressive CD38+ZAP-70+ as compared to indolent CD38−ZAP-70− chronic lymphocytic leukemia (CLL) cases. Here, we measured Pgrn plasma concentrations by enzyme-linked immunosorbent assay (ELISA) in the Essen CLL cohort of 131 patients and examined Pgrn for association with established prognostic markers and clinical outcome. We found that high Pgrn plasma levels were strongly associated with adverse risk factors including unmutated IGHV status, expression of CD38 and ZAP-70, poor risk cytogenetics (11q-, 17p-) as detected by flourescence in situ hybridization (FISH) and high Binet stage. Pgrn as well as the aforementioned risk factors were prognostic for time to first treatment and overall survival in this series. Importantly, these results could be confirmed in the independent multicentric CLL1 cohort of untreated Binet stage A patients (n = 163). Here, multivariate analysis of time to first treatment revealed that high risk Pgrn (HR = 2.06, 95%-CI = 1.13–3.76, p = 0.018), unmutated IGHV status (HR = 5.63, 95%-CI = 3.05–10.38, p<0.001), high risk as defined by the study protocol (HR = 2.06, 95%-CI = 1.09–3.89, p = 0.026) but not poor risk cytogenetics were independent prognostic markers. In summary our results suggest that Pgrn is a novel, robust and independent prognostic marker in CLL that can be easily measured by ELISA.

Progressive multifocal leukoencephalopathy after treatment with rituximab, fludarabine and cyclophosphamide in a patient with chronic lymphocytic leukemia

With the introduction of potent immunosuppressive agents, progressive multifocal leukoencephalopathy (PML) as a lethal complication of immune suppression has gained more and more attention during recent years [1]. PML is a mostly fatal, demyelinating disease of the brain caused by the John Cunningham (JC) virus. In diff erent populations the prevalence of this virus is up to 68% in the elderly. It persists in kidney cells and has been detected in the urine of healthy individuals in up to 19% [2]. Reduced immunity caused by HIV/AIDS, cancer, immunosuppressive agents or stem cell transplant can induce reactivation of the JC virus and infection of oligodendrocytes, typically leading to demyelinating brain lesions. As the disease progresses, multiple neurologic symptoms develop and may alter over time, sometimes mimicking the clinical picture of multiple sclerosis or strokes. Patients suff ering from chronic lymphocytic leukemia (CLL), one of the most common indolent lymphomas in the Western world, seem to be more prone to PML (incidence of PML in non-hematologic malignancies: 0.07%; incidence in CLL: 0.5%). While CLL is inherently associated with an immune defect, treatment of CLL with immunosuppressive drugs such as fl udarabine and/or rituximab further increases

Chronische lymphatische Leukämie

Chronic lymphocytic leukemia (CLL) is the most common form of leukemia in the Western world. Median age at diagnosis is around 70 years. To confirm the diagnosis more than 5000 B-lymphocytes/µl need to be present. The expression of the typical surface markers CD5, CD19, CD20 and CD23 has to be confirmed by flow cytometry. A bone marrow biopsy is not mandatory for the diagnosis. Before start of treatment the assessment of 17 p deletion and/or TP53-mutational status is recommended. Treatment indications include stage Binet C or signs of an active disease as rapidly progressive lymphadenopathy or organomegaly together with physical limitation, B symptoms that cannot be tolerated, rapidly deteriorating blood values, or rapidly increasing leukocyte counts (Lymphocyte doubling time less than 6 months). The patients physical condition has major impact on the treatment decision. Currently immunochemotherapy with fludarabine, cyclophosphamide and the CD20-antibody rituximab (FCR) is the standard of care in previously untreated and physically fit patients. An alternative regimen is the combination of bendamustine and rituximab (BR) or ofatumumab. Physically compromised patients can be treated with the oral drug chlorambucil in combination with an anti-CD20 antibody. Due to high morbidity and mortality, allogeneic stem cell transplantation is limited to a small group of patients and should be discussed in a high-risk situation, such as 17 p deletion and/or TP53-mutation, lack of response to standard therapy or early relapse. Recently several new chemo-free treatment options have been introduced within clinical trials. Among them are monoclonal antibodies, most of them targeting the CD20 molecule: besides the licensed drugs rituximab and ofatumumab, obinutuzumab, in combination with chemotherapy, has recently shown high clinical efficacy in front-line treatment of elderly patients with CLL. Novel agents have been designed to block aberrant signaling from the B-cell receptor. Ibrutinib acts by inhibiting the Brutons tyrosine kinase (BTK) while idelalisib represents a first-in-class specific inhibitor of the phosphoinositol-3 kinase (PI3K) delta isoform. Another class of drugs with potential impact for chemo-free treatment strategies in CLL is the BH3-mimetic inhibitor of the Bcl-2 family of pro-survival proteins, ABT-199. Given all these novel agents and targets, chemo-free or at least chemo-reduced concepts may become reality in the near future for our patients suffering from CLL.