In NEJM this week, researchers from the US and Europe present findings from a study looking at the underlying genetic causes of hair-cell leukemia. The researchers performed massively parallel whole-exome sequencing of leukemic and matched normal cells from the blood of a patient with hair-cell leukemia, and found five missense somatic clonal mutations, including a heterozygous mutation in the BRAF gene that results in the creation of the BRAF V600E protein. The same mutation was found in 47 other hair-cell leukemia patients who were evaluated with Sanger sequencing, but not in 195 patients with other peripheral B-cell lymphomas or leukemias, the authors write. "The BRAF V600E mutation was present in all patients with hair-cell leukemia who were evaluated. This finding may have implications for the pathogenesis, diagnosis, and targeted therapy of hair-cell leukemia," they add.
Also in NEJM this week, FDA researchers write about the risks and benefits of 5α-reductase inhibitors for the prevention of prostate cancer, an issue which continues to generate much debate in the medical and scientific communities. Two recent trials of 5α-reductase inhibitors finasteride and dutasteride have shown an overall relative reduction of 23 percent to 25 percent in prostate cancer diagnoses, however, the reductions were only observed in the incidence of low-grade prostate cancers, the authors write. "The conclusion drawn by the [FDA] advisory committee in December was that finasteride and dutasteride do not have a favorable risk–benefit profile for the proposed use of chemoprevention of prostate cancer in healthy men," they add. "The FDA agrees with this assessment."