Targeted therapy for chronic myeloid leukemia (CML) has been shown to be successful in extending patients’ life expectancy by controlling the reproduction of cancerous cells with an oncogene not found in healthy cells, a cancer expert said yesterday on World CML Day.
Hsu Szu-chun (徐思淳), director of the hematology and oncology division at National Taiwan University Hospital, said that the patient who has received targeted therapy for the longest time in Taiwan — 13 years — has nearly no oncogenes in his blood cells. Oncogenes are genes that can potentially cause cancer. The one associated with CML is called the Philadelphia chromosome.
Some women taking targeted medication have to pair it with long-term contraceptives to prevent birth defects. However, a small portion are able to conceive after suspending their therapy temporarily with their doctor’s approval and then resume treatment after delivery, he said.
A woman with two children surnamed Wu (吳) was 29 when she was diagnosed with CML and told she had less than a year to live.
Since undergoing targeted therapy, Wu said she feels she has been given “an extra 12 years of life,” which allowed her to attend her elder son’s kindergarten and junior-high school graduations. She is now looking forward to seeing him graduate from senior-high school in a year.
Targeted drug treatment has changed the lives of many CML patients, Hsu said, adding that 100 to 200 new cases are diagnosed each year in Taiwan.
Most patients diagnosed in the disease’s acute phase die within a year, but targeted therapy can help keep CML in the initial phase for five to 10 years, or longer, Hsu said.
He said that some Asian female patients have reported what they find to be a positive side effect of the treatment: preventing tanning.
The therapy has replaced stem cell transplants using bone marrow or umbilical cord blood and rewritten the treatment guidelines for CML, Hsu said.
Between 30 percent and 40 percent of patients undergoing the therapy have a hard time coping with side effects such as abdominal pain and fluid buildup, or experienced oncogene mutation that rendered the drugs ineffective, he said. This is why the National Health Insurance Administration decided to cover second-generation targeted drugs for future patients and those undergoing treatment, Hsu added.
He said that second-generation drugs can get the disease under control faster and may improve patients’ quality of life, as well as extending their life expectancy.