Which of the following is NOT a characteristic of sarcomas?

Sarcomas are a diverse group of cancers that primarily arise from connective tissues, which includes bone, cartilage, muscle, fat, and vascular tissues. This classification is important because it distinguishes sarcomas from carcinomas, which originate from epithelial tissues.

Among the characteristics of sarcomas, they are indeed more common in certain pediatric populations, particularly in specific types known as pediatric sarcomas, such as Ewing sarcoma and rhabdomyosarcoma. This pediatric prevalence is significant in understanding the epidemiology of the disease.

The involvement of soft tissues is another key aspect, as sarcomas can occur in any connective tissue, including muscles and adipose (fat) tissue. This characteristic highlights the versatility and diverse presentations of sarcomas within the body.

However, sarcomas are not typically found in the brain. Brain tumors are primarily classified as gliomas or meningiomas rather than sarcomas, which are more commonly located in soft tissue or bone. Thus, stating that sarcomas are typically found in the brain contradicts the fundamental characteristics of these tumors, making it the correct choice for the question regarding what is NOT a characteristic of sarcomas.