Cure by Robin Cook

With her young son's potentially fatal neuroblastoma in complete remission, New York City medical examiner Laurie Montgomery returns to work at the Office of Chief Medical Examiner. Worried that she still has what it takes, Laurie finds her first case back to be a dangerous puzzler, involving organized crime and two start-up bio-tech companies caught in a zero-sum game. Satoshi Machita, a former Kyoto University researcher, is set to own a valuable patent controlling pluripotent stem cells destined to spark a trillion-dollar industry of regenerative medicine. When he dies on a crowded New York subway platform, Laurie must decide whether his death was natural or something fiendish. Behind the scenes, there are people who would like to see Laurie as far away from the investigation as possible. Despite threats against her, Laurie presses on, until they extend to the person she loves most in the world: her son, JJ. Suddenly Laurie must face solving the crime and saving her son's life.