Chronic lymphocytic leukaemia is the most prevalent leukaemia in Western countries. It is an incurable disease characterized by a highly variable clinical course. Chronic lymphocytic leukaemia is an ideal model for studying clonal heterogeneity and dynamics during cancer progression, response to therapy and/or relapse because the disease usually develops over several years. Here we report an analysis by deep sequencing of sequential samples taken at different times from the affected organs of two patients with 12- and 7-year disease courses, respectively. One of the patients followed a linear pattern of clonal evolution, acquiring and selecting new mutations in response to salvage therapy and/or allogeneic transplantation, while the other suffered loss of cellular tumoral clones during progression and histological transformation.

The prognostic impact of biallelic ATM abnormalities (ATM mutation and concurrent 11q deletion) remains unknown. We studied ATM, BIRC3, SF3B1, and NOTCH1 genes in 118 treatment-naïve CLL patients at diagnosis. Patients with biallelic ATM alteration had a similar time to first treatment (TTFT) and shorter overall survival (OS) compared with patients with isolated 11q deletion and shorter TTFT and OS when compared to patients with wild-type ATM. Furthermore, biallelic ATM alteration (HR: 6.4; p ≤ 0.007) was significantly associated with an increased risk of death similar to p53 deletion (HR: 6.1; p ≤ 0.004), superior to 11q deletion alone (HR: 2.8; p ≤ 0.022) and independent of other significant parameters such as age, advanced clinical stage, and complex karyotype. Our results suggest the identification of ATM mutations in CLL patients with 11q deletion at diagnosis is clinically relevant and predicts disease progression, poor response to the treatment, and reduced OS independent of other molecular prognostic factors.

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Chronic Lymphocytic Lymphoma (CLL) is a heterogeneous disease in which many important factors for its prognosis have been identified. The normal functioning of p53 is one of the most critical barriers against cancer; therefore, if it has a deletion and/or mutation, it is a robust biomarker for the therapeutic response in CLL. The possibility was raised that some germline single - nucleotide polymorphisms of TP53 in healthy populations may also affect p53 function. One of the most studied polymorphisms of the TP53 gene is codon 72 in exon 4, a CGC to CCC transition (R72P), due to its potential effect on cancer risk. As with many types of cancer, its association with a worse prognosis in CLL is unclear. We analyzed the relationship of the genotypes of the TP53 codon 72 polymorphism in a large cohort of patients with CLL, to demonstrate the association of codon 72 with the evolution of the disease. Using the IDIPHIM patient database, 558 patients with a diagnosis of CLL were included, with clinical data, immunophenotype studies, FISH, IgHV, and karyotype, at the time of diagnosis and during follow-up. The TP53 codon 72 Arg/Arg, Arg/Pro, and Pro/Pro genotypes were analyzed using RT-PCR and Sanger sequencing techniques. After analyzing the sample of patients, 321 patients with the Arg/Arg genotype, 202 with the Arg/Pro genotype, and 35 with the Pro/Pro genotype were found. In the comparative analysis of the three groups, the patients with the Pro/Pro genotype had a higher number of patients in advanced stages B and C. The latter had a significant association with Binet staging (p = 0.002) compared to the other groups. Likewise, patients with the Pro/Pro genotype had a higher incidence of Richter transformation, whose association was significant (p = 0.013). Also, the patients who were within the Pro/Pro genotype group showed a significant association (p = 0.030) with the Time to the first treatment (TFT), also observing that the group of patients with the Arg/Pro genotype had a more considerable time until your first treatment. 19.7% (110/558) had a second neoplasm, having a significantly higher association with the homozygous groups (Arg/Arg and Pro/Pro) than with the Arg/Pro group, which on the contrary, had fewer second neoplasms (p = 0.016) (see Table 1). Regarding the type of tumors, we found 14.5% of the bladder, 14.5% of the skin, 14.5% of the colon, 13.6% of the prostate, and 12.7% of the lung. No associations were found between Codon 72 and CD38+, ZAP70+, complex karyotype, IgHV, NOTCH-1, del 11q, 12+, p53, del 13q, TP53 mutation. Still, when forming a group between the p53 deletion and TP53 mutation, if significant differences were found (p = 0.023), Pro / Pro group had the highest percentage. The overall survival was 156.32 months (139.92 - 172.72), showing that patients with the Arg/Pro genotype live 40 months more significantly than the other groups (p = 0.028) (see Figure 1). Finally, in the multivariate analysis, age, complex karyotype, 11q deletion, p53 deletion, unmutated IgHV, and Pro/Pro genotype at codon 72 were identified as independent variables associated with an increased risk of death (see Table 2). In conclusion, the Pro/Pro genotype of TP53 Codon 72 has a potential role in the progression and the higher mortality of patients with CLL. Conversely, the Arg / Pro genotype was associated with a lower incidence of second malignancies and higher overall survival. Disclosures No relevant conflicts of interest to declare.

Background:The international prognostic index for chronic lymphocytic leukemia (CLL-IPI) has been recently established as a powerful tool for risk stratification of CLL patients with regard to both overall survival (OS) and time to first treatment (TTFT). Aims: The aim of this study was to examine the applicability of CLL-IPI to Serbian CLL patients. Methods: Our cohort consisted of 82 unselected CLL patients diagnosed and managed within the Clinic of Hematology, Clinical Center of Serbia, Belgrade, Serbia during the previous 15 years. The data regarding initial clinical and laboratory features were collected retrospectively from patient medical records. The analyses of cytogenetics (done by fluorescent in situ hybridization (FISH)), mutational status of immunoglobulin heavy variable (IGHV) genes and TP53 gene were performed from samples collected prospectively in the period between diagnosis and the first treatment. The data regarding age, stage (Rai and Binet), b2-microglobulin (b2m), IGHV mutational status and FISH were available for all 82 patients, while TP53 status was known for 38 patients (46%). All the patients were assigned with CLL-IPI and stratified according to The international CLL-IPI working group. TTFT and OS analyses were performed using Kaplan-Meier and Cox regression methods. Results:The median age at diagnosis was 59 (range 38-81). Male to female ratio was 2.4. Fifty percent of patients were diagnosed with Binet A stage, 32% with Binet B, and 18% with Binet C. Median levels of serum b2m and lactate dehydrogenase (LDH) at diagnosis were 3.12 mg/L (range 0.2-11.5 mg/L) and 374 IU/L (range 80-930 IU/L), respectively. Regarding IGHV genes, 38 patients (41.5%) were mutated, while the rest were unmutated cases. Normal karyotype, del(13q), trisomy(12), del(11q), and del(17p) were detected by FISH in 32.9%, 43.9%, 7.3%, 13.4%, and 2.4%, respectively. TP53 was mutated in 4/38 patients. According to the CLL-IPI, 18 patients (22%) were assigned with low risk, 33 (40.2%) intermediate risk, 28 (34.1%) high risk, and 3 (3.7%) with very high risk. After a median of 55 months (range 0-169 months) patients were treated as follows: 51 (81%) with fludarabine-based therapy (71% FC and 29% FCR), 7 (8.5%) with chlorambucil, and 5 (6.1%) with cyclophosphamide, vincristine, and prednisone (COP). Patients experienced significantly different median TTFT across risk groups: for low-risk patients, median TTFT was not reached, for intermediate risk was 47 months, for high risk 31 months, and for very high risk 1 month (Log-rank test across groups p < 0.001) (Figure 1A). Cox regression analysis confirmed that the risk of treatment commencement increased significantly with every extra score point (HR 1.542; 95%CI 1.337-1.777; p < 0.001). Median OS in our cohort was 9 years (108 months) (range 4-191 months). Median OS was not reached in the low-risk group, while in intermediate, high, and very high-risk groups were 94 months, 78 months, and 17 months, respectively (Log-rank test across groups p < 0.001) (Figure 1B). Cox reg...