Shown is one possible approach to treating patients that is based on known clinical and laboratory factors as well as genetic alterations identified by Kataoka et al. Specifically, patients with chronic type, unfavorable disease who harbor 1 or more of the 3 genetic alterations would receive intensive therapy for aggressive disease whereas those who do not harbor any of those alterations may not require intensive therapy. Future analyses and prospective trials are needed to address whether this type of approach can refine patient selection and maximize therapeutic benefit. AZT, zidovudine; FISH, fluorescent in situ hybridization. The microscopic images were kindly provided by Peter Maslak, Memorial Sloan Kettering Cancer Center. Professional illustration by Patrick Lane, ScEYEnce Studios.