AbstractObjectivesT-cell prolymphocytic leukemia (T-PLL) is a rare mature T-cell leukemia usually characterized by inv(14)(q11.2q32)/t(14;14)(q11.2;q32). In this study, we aimed to investigate the clinicopathologic features and molecular profile of T-PLL associated with t(X;14)(q28;q11.2).MethodsThe study group included 10 women and 5 men with a median age of 64 years. All 15 patients had a diagnosis of T-PLL with t(X;14)(q28;q11.2).ResultsAll 15 patients had lymphocytosis at initial diagnosis. Morphologically, the leukemic cells had features of prolymphocytes in 11 patients, small cell variant in 3, and cerebriform variant in 1. All 15 patients had hypercellular bone marrow with an interstitial infiltrate in 12 (80%) cases. By flow cytometry, the leukemic cells were surface CD3+/CD5+/CD7+/CD26+/CD52+/TCR α/β+ in 15 (100%) cases, CD2+ in 14 (93%) cases, CD4+/CD8+ in 8 (53%) cases, CD4+/CD8– in 6 (40%) cases, and CD4–/CD8 + in 1 (7%) case. At the cytogenetic level, complex karyotypes with t(X;14)(q28;q11.2) were seen in all 15 patients assessed. Mutational analysis showed mutations of JAK3 in 5 of 6 and STAT5B p.N642H in 2 of 6 patients. Patients received variable treatments, including 12 with alemtuzumab. After a median follow-up of 17.2 months, 8 of 15 (53%) patients died.ConclusionsT-PLL with t(X;14)(q28;q11.2) frequently shows a complex karyotype and mutations involving JAK/STAT pathway, and it is an aggressive disease with a poor outcome.
Mutagen Sensitivity Has High Heritability: Evidence from a Twin Study
Abstract Despite numerous studies showing that mutagen sensitivity is a cancer predisposition factor, the heritability of mutagen sensitivity has not been clearly established. In this report, we used a classic twin study design to examine the role of genetic and environmental factors on the mutagen sensitivity phenotype. Mutagen sensitivity was measured in peripheral blood lymphocytes from 460 individuals [148 pairs of monozygotic (MZ) twins, 57 pairs of dizygotic (DZ) twins, and 50 siblings]. The intraclass correlation coefficients were all significantly higher in MZ twins than in dizygotes (DZ pairs and MZ-sibling pairs combined) for sensitivity to four different mutagen challenges. Applying biometric genetic modeling, we calculated a genetic heritability of 40.7%, 48.0%, 62.5%, and 58.8% for bleomycin, benzo[a]pyrene diol epoxide, γ-radiation, and 4-nitroquinoline-1-oxide sensitivity, respectively. This study provides the strongest and most direct evidence that mutagen sensitivity is highly heritable, thereby validating the use of mutagen sensitivity as a cancer susceptibility factor. (Cancer Res 2006; 66(12): 5993-6)