Many children in Honduras receiving the most advanced treatment for ALL, the most common type of childhood cancer, still die because their families must abandon therapy or because the children succumb to infections.
ALL cure rates in some countries with limited resources are less than 35 percent, while the cure rates in developed countries have reached 80 percent.
"This 'survival gap' shows the difference between what is medically possible and what can be practically achieved in a country like Honduras," said Scott Howard, M.D., director of clinical trials in the St. Jude International Outreach Program, and co-author of the study. "The goal of the St. Jude International Outreach Program is to close such survival gaps."
More than 70 percent of the world's children live in countries with limited resources.
The investigators found that the major reason that families abandon children's treatment was the prolonged travel times faced by families in distant parts of Honduras. These families sometimes must travel more than five hours for weekly chemotherapy treatment in the capital city, Tegucigalpa.
"Families face not only the costs of the bus ticket, but also the time spent away from home and work--a major obstacle to those with limited income," said Monika Metzger, M.D., also of St. Jude. Metzger is the lead author of The Lancet report.
Cultural factors also play an important role in discouraging some parents from keeping their children in therapy.
"Some parents may think that initial improvement means their child is cured," Metzger said. "Others are skeptical that cure is even possible, so they abandon further treatment."
Friends and family members may also dissuade parents from continuing conventional therapy, instead suggesting alternative treatments. However, the study found that after the first year, parents better understood the disease and its treatment and were less likely to abandon the therapy. This gradual acceptance of treatment also reflected the families' greater hope for a cure and their increased trust in the medical staff.
"This demonstrates the importance of early intervention to avoid misunderstandings," Metzger said.
According to Raul C. Ribeiro, M.D., director of the St. Jude International Outreach Program, improving survival rates in countries with limited resources requires a two-pronged approach.
"Our findings clearly show that it's not enough to just share new medical treatments with countries like Honduras," Ribeiro said. "This shows that we must translate these treatments into cultural and economic settings that are different from those in the U.S." Infection was another barrier to survival, according to the study.
The high rate of infection was attributed--at least in part--to overcrowding in inpatient and outpatient areas, the small number of hand-washing stations and the absence of soap and paper towels.
The report's authors analyzed the causes of treatment failure for 168 patients admitted to Hospital Escuela over the course of two years. Only 38 percent of children survived disease-free two years after diagnosis, compared to about 90 percent of St. Jude patients with ALL at the same stage of treatment.
The study found that the outcome of children with ALL in poor countries could be improved by interventions that reduce the rate of abandonment, such as funding for transportation, satellite clinics for administration of chemotherapy, treatment of infections, educational programs for families and nurses, and parent support groups. Many of these measures have already been implemented in Honduras. A follow-up study will be performed to assess their effectiveness.
"Discovering the reasons that Honduran children with ALL are not successfully cured is only the beginning," Metzger said. "We will not be satisfied until children in all parts of the world enjoy the same high cure rates that children treated at St. Jude experience." Other authors of the report include Michael L. Hancock, Zhe Zhang, Ching-Hon Pui and Judy Wilimas (St. Jude); and Ligia C. Fu, Armando Pena and Rene Stefan (Hospital Escuela).
This work was supported in part by a Cancer Center Support (CORE) grant from the National Cancer Institute, a Center of Excellence grant from the State of Tennessee and ALSAC.
St. Jude Children's Research Hospital
St. Jude Children's Research Hospital is internationally recognized for its pioneering work in finding cures and saving children with cancer and other catastrophic diseases. Founded by late entertainer Danny Thomas and based in Memphis, Tennessee, St. Jude freely shares its discoveries with scientific and medical communities around the world. No family ever pays for treatments not covered by insurance, and families without insurance are never asked to pay. St. Jude is financially supported by ALSAC, its fundraising organization. For more information, please visit www.stjude.org.
Journal
The Lancet