Molecular and Clinical Studies of Bone and Soft Tissue Tumors

The goal of this observational study is to learn whether tumors of bone and soft tissue can be sorted into groups by their genes. Today these tumors are named mainly by how they look under a microscope. There are more than 150 names in use. The same tumor can be given different names by different doctors. The study includes people of any age with a bone or soft tissue tumor. All of them had tissue sampled at Karolinska University Hospital in Stockholm, Sweden. The main questions it aims to answer are: Can tests of a tumor's genes sort these tumors into clearer groups than the names used today? How often does a tumor's gene group differ from the name it was given at diagnosis? Can a computer program tell these groups apart from scanned pictures of the tissue? Researchers will compare the groups found by the gene tests with the diagnoses given at the time. They will also look at how each group did over the years that followed. This shows which way of sorting tumors better matches what happened to participants. Participants will not have extra visits, tests, or treatment for this study. The study does not change anyone's care. Researchers will: Use tumor tissue that was already taken as part of regular care Read the DNA and RNA in the tumor, which carry its genetic instructions Read the chemical marks on the tumor's DNA that switch genes on and off Scan the glass slides of the tissue into digital pictures Collect facts about treatment and health from medical records Participants who are newly diagnosed will also be asked for a blood sample. Blood shows which gene changes a person was born with and which ones started in the tumor. If the study finds a gene change that matters for a participant's care, the study team tells the treating doctors through normal hospital routines.