New Cancer Threat Lurks Long After Cure

Secondary cancers now make up the sixth-most-common group of malignancies, in part because more survivors are living longer.

Watching Robin Roberts tear up in front of millions of viewers on “Good Morning America” last month, I cried, too.

With equal measures of courage and fear, Ms. Roberts, an anchor of the show and a breast cancer survivor, explained that the life-saving treatment she received five years ago was responsible for a new diagnosis, this time myelodysplastic syndrome (MDS), a rare blood and bone marrow disease once called preleukemia.