Low-income Americans ages 18 to 64 with cancer saved about US$1,250 per year on treatment within seven years of the 2014 rollout of the Affordable Care Act^[1], according to my recent study^[2].

Those patients either personally earned or were in families that made $17,609 or less per year^[3] and therefore were eligible for Medicaid^[4], the government’s primary health insurance program for low-income Americans.

But adults under...