Infantile fibroblastic and myofibroblastic tumors are the second most prevalent type of soft tissue neoplasms in pediatric patients < 1 years old. Although the majority of these tumors are either benign or low-grade, there are certain subtypes with a higher tendency toward malignancy. Congenital infantile fibrosarcoma (CIFS) is one such high-risk group. CIFS patients, who are nearly always less 2 years old, present with morphologically ambiguous tumors that can resemble a range of other infantile neoplasms of varying clinical course, including myofibroma/myofibromatosis, lipofibromatosis and fibrous hamartoma of infancy, primitive myxoid mesenchymal tumor of infancy (PMMTI), and dermatofibrosarcoma protuberans (DFSP).

Gliomas are rare brain tumors that can affect individuals of all ages. While studies are plentiful on pediatric and adult gliomas, infant cases are historically understudied – an unfortunate fact, considering central nervous system tumors are most common (and deadly) in this age group. This research team sought to account for that lack of data by cytogenetically analyzing infant glioma samples collected between 1986 and 2017. The team was able to divide these tumors into three genetic subtypes that were tightly tied to clinical outcome. Additionally, they found that many of the tumors harbored just a single genetic aberration, evidence that infant gliomas are usually single driver tumors.