Pediatric Cancers Differ from Adult Cancers, and Need Different Treatment Plans, Say CHOP Experts

Physician-scientists from Children’s Hospital of Philadelphia (CHOP) contributed crucial data and expertise to the first pan-cancer analysis of children’s cancer, published today in the journal Nature. Pan-cancer analyses identify similarities and differences among the biological changes across diverse types of cancer, with the aim of discovering insights for improved care.

In this new study, the researchers found important differences in how cancers develop in children compared to how they develop in adults. For instance, they identified 142 genes that drive pediatric cancers, but only 45 percent of those genes match genes found in adult pan-cancer studies. This implies that precise treatments need to be better customized for children.

Stephen P. Hunger, MD Co-authors from CHOP lead the two largest datasets in the study, which analyzed DNA samples from nearly 1,700 patients from multiple centers across five groups of pediatric cancers: acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), neuroblastoma, Wilm’s tumor and osteosarcoma. The study team, led by Dr. Jinghui Zhang of St. Jude Children’s Research Hospital, searched for mutations and other variations in DNA sequences. All the patients were in clinical trials sponsored by the Children’s Oncology Group, and the datasets came from the TARGET project of the National Cancer Institute.

Stephen P. Hunger, MD, CHOP’s Chief of Oncology, leads the TARGET team for acute lymphoblastic leukemia, (ALL).  He explained, “As pediatric centers have developed precision medicine strategies, many have relied on diagnostic panels developed to detect mutations common in adult cancers. In contrast, CHOP has developed diagnostic panels specific to mutations common in pediatric cancers — many of which occur only rarely in adult cancers.”

John M. Maris, MD CHOP’s John M. Maris, MD, who leads the neuroblastoma TARGET team, echoed the importance of the study, validating the need to focus on the unique attributes of pediatric cancers. “This collaborative project proves the concept that childhood cancers are not ‘small adult tumors.’ They show unique genetic changes. Thus, precision diagnostic and therapeutic strategies for childhood cancers will be very different than those being developed for common adult malignancies.”

Xiaotu Ma et al, “Pan-cancer genome and transcriptome analyses of 1,699 paediatric leukaemias and solid tumours,” Nature, published online Feb. 28, 2018, to appear in print March 15, 2018.

Read an article about the study posted on Nature.