Survivors of the most common type of childhood leukemia may need careful cancer screening for decades after leukemia treatment.
That finding comes from a study of 2,169 children who achieved complete remission from acute lymphoblastic leukemia, which is one of the most curable childhood cancers, write the researchers.
They included Nobuko Hijiya, MD, of the oncology department at St. Jude Children’s Research Hospital in Memphis, Tenn.
The children were all treated at St. Jude Children's Research Hospital between 1962 and 1998.
They were followed for two to 41 years (average follow-up: nearly 19 years). During the follow-up period, 123 patients developed another cancer that was not leukemia.
On average, more than 23 years passed between the patients' diagnosis with childhood acute lymphoblastic leukemia and the diagnosis of their second cancer.
Most of the second cancers were "low-grade" tumors, write Hijiya and colleagues in The Journal of the American Medical Association.
Increased Cancer Risk
In one analysis, the researchers deliberately skipped two of the most common low-grade tumors. Even after that adjustment, cancer risk rose for 30 years after remission from childhood acute lymphoblastic leukemia.
Cancer becomes more common with age. But the cancer risk for the childhood leukemia survivors was more than 13 times higher than for the general public, even when the researchers only looked at high-grade tumors.
"The risk of high-grade tumors ... significantly exceeds the risk in the general population, underscoring the need for continued careful follow-up of acute lymphoblastic leukemia survivors," write Hijiya and colleagues.
Their study doesn't show why acute lymphoblastic leukemia in childhood may carry a long-lasting cancer risk.