Report of two novel chromosomal translocations in chronic lymphocytic leukemia

Report of novel chromosomal abnormalities in a series of 130 chronic lymphocytic leukemia patients studied by classic cytogenetic analysis

One-hundred-and-thirty typical, unselected CLL cases were studied by conventional cytogenetic analysis. Seventy-three patients (56.2%) had normal karyotype ('normal sub-group'), while 57/130 patients (43.8%) had abnormal karyotype. Twenty-two of 57 patients (38.6%) carried more than one abnormality. Six novel chromosomal abnormalities were detected in five patients: (i) t(3;13)(q14;q34); (ii) t(Y;11)(q12;q23), del(13)(q12q14); (iii) dic(3;11)(p21;q23); (iv) t(3;5)(q29;q23); (v) t(3;22) (p21;q13); and (vi) t(1;13)(p12;q12). Three of five patients carrying novel translocations had progressive disease. The true biological and clinical significance of novel chromosomal abnormalities remains to be determined.

Clinical, immunophenotypic, and molecular profiling of trisomy 12 in chronic lymphocytic leukemia and comparison with other karyotypic subgroups defined by cytogenetic analysis

In a cohort of 130 unselected chronic lymphocytic leukemia (CLL) patients, 73 cases had normal karyotypes, 57 cases had abnormal karyotypes, and 22/57 cases carried more than one abnormality. Trisomy 12 (+12) was the most common abnormality (26/130 cases; 20%), and 17/26 cases had isolated +12. Del(13q)/t13q/-13 was detected in 19/130 cases (14.6%), and 5/19 cases had isolated del(13)(q12q14). Deletion (11)(q23) and del(17p)/-17 were detected in 5/130 cases, respectively. CD38 expression was significantly more frequent in the +12/11q/17p versus the normal/del(13q) subgroups. A significant association was detected between +12 and FMC7 positivity. IGHV-unmutated cases were significantly more frequent in the +12/11q/17p subgroups. Patients with normal karyotype/del(13q) had a longer median time to progression versus the patients in the +12/11q/17p subgroups. According to multivariate analysis, only IGHV mutation status remained a statistically significant variable for progression-free survival (PFS). Furthermore, IGHV mutation status and clinical stage at diagnosis were the only significant prognostic factors for overall survival. Among Binet-A patients, significant parameters for shorter PFS were +12 or 11q/17p aberrations, CD38 expression, and IGHV unmutated status. In multivariate analysis, only CD38 expression and IGHV-unmutated status retained statistical significance for PFS. In conclusion, trisomy 12 in CLL is characterized by considerable heterogeneity and seems to be associated with disease progression.