HEMATOLOGY AND ONCOLOGY: Edited by Stephen Hunger
Cancer is the most common cause of death from illness in children. The incidence rate for cancer among children and adolescents in the United States increased at a rate of 0.6% annual percentage change during the period of 1975–2006, particularly for acute lymphoblastic leukemia (ALL) and central nervous system (CNS) tumors . Importantly, mortality rates for all pediatric cancers decreased by more than 50% during the same period, although the improvements did not occur equally between all tumors . Reports from the past year show that the 5-year survival rate for children and adolescents enrolled in Children's Oncology Group ALL clinical trials, which enroll about 70% of predicted United States ALL cases that occur among persons 0–19.99 years old, increased from 83.7% for those enrolled in 1990–1994 to 90.3% for those enrolled in 2000–2005 and 92.3% for 2006–2009 [2,3]. In parallel, there has been an explosion of knowledge concerning the genetic landscape of childhood cancers over the past several years that should ultimately lead to new therapies that are both more effective and less toxic. Major advances have also occurred in knowledge and treatment of the nonmalignant hematological disorders of childhood. Against this backdrop, this issue of Current Opinion in Pediatrics presents detailed reviews of new developments and the current state of knowledge and clinical practice in four important areas.
Carlos Rodriguez-Galindo and colleagues provide a detailed and authoritative review of global challenges in pediatric oncology. Most children who develop cancer do not live in North America and Western Europe, where impressive survival improvements have occurred over the past 50 years. An estimated 90% live elsewhere, most in countries with limited resources where treatment of cancers that are highly curable in high resource countries presents a variety of challenges. As summarized by Dr Rodriguez-Galindo, major advances in treatment of childhood cancer have been made in many such countries over the past 10–20 years, often facilitated by ‘twinning’ relationships with centers in high resource countries.
Saro Armenian and Leslie Robison present a detailed discussion of the many issues that affect more than 363 000 survivors of childhood cancer, a number that increases steadily every year. This group includes almost 100 000 persons who have survived more than 30 years after diagnosis of childhood cancer. These survivors are active in many different areas. Pediatricians and internists care for them in their practices, and will encounter them in everyday life, often not knowing of their past history or the challenges that they face. Most childhood cancer survivors lead active and productive lives. At my hospital, childhood cancer survivors are employed in a variety of different roles including hospital administration, as nurses on the pediatric oncology unit, and as faculty members and fellows in our program. However, many face health problems that are unique and are important for physicians to know about as they care for these patients, and also a critical area for research both on the natural history of these problems and on interventions designed to decrease the incidence of various toxicities and/or ameliorate symptoms.
Brian Branchford, Paul Monahan, and Jorge DiPaola discuss new developments in the treatment of pediatric hemophilia and clotting disorders. There have been tremendous advances in this area over the past few decades that followed a devastating time during which most US patients with severe hemophilia were infected with HIV due to transfusion of clotting factor concentrates contaminated with that virus. Thankfully, this period is now a distant memory and most current trainees will never see a child with hemophilia infected with HIV. New methods in recombinant DNA technology have revolutionized treatment with virus free recombinant clotting factor concentrates. Treatment for many patients has moved from on demand treatment of bleeds after they happen to prophylactic use of clotting factor concentrates to prevent bleeding from occurring. This change has had enormous impact on the quality of life for persons with hemophilia. This review discusses the large variety of new clotting factor concentrates now available for use or well along the development pipeline, and the current status and promise of corrective gene therapy for hemophilia and other hemostatic disorders.
Jennifer Bruny and Timothy Crombleholme provide a fascinating review of management issues for solid tumors that occur in infants. Because of the remarkable improvements that have occurred in fetal imaging, primarily sonography but also including MRI, many tumors can be diagnosed, or suspected, during fetal life. This has created the possibility of fetal surgery to remove tumors or correct defects that may be otherwise lethal to the fetus or lead to major complications in the immediate perinatal period. No longer are neonatologists faced with the unexpected delivery of a child with a large sacrococcygeal teratoma. Many of these tumors are diagnosed on routine prenatal ultrasounds, leading to careful management of the pregnancy by a team of experienced perinatologists and pediatric surgeons with controlled delivery and planned surgery shortly after birth, and sometimes now even prenatal intervention.
I hope that these reviews provide you with a sense of the exciting changes that are occurring in treatment of children with cancer and nonmalignant blood disorders. Tremendous improvements have taken place in the 25 years since I joined this field and I anticipate that the next 25 years will see many more exciting developments that will lead to improved outcomes for children worldwide.
Conflicts of interest
Stephen Hunger is the Ergen Family Chair in Pediatric Cancer. There are no conflicts of interest.
1. Smith MA, Seibel NL, Altekruse SF, et al. Outcomes for children and adolescents with cancer: challenges for the twenty-first century. J Clin Oncol 2012; 28:2625–2634.
2. Hunger SP, Lu X, Devidas M, et al. Improved survival for children and adolescents with acute lymphoblastic leukemia between 1990 and 2005: a report from the children's oncology group. J Clin Oncol 2012; 30:1663–1669.
3. Hunger SP, Loh ML, Whitlock JA, et al
. Children's Oncology Group's 2013 Blueprint for Research: Acute Lymphoblastic Leukemia. Pediatr Blood Cancer (in press).