In this episode the audience will enjoy a great discussion of the growing potential of methylome and copy number profiling, a technique well established for the classification of brain tumors, in bone and soft tissue tumors diagnosis.

Nuclear overexpression of FOS and FOSB have emerged as a reliable surrogate markers to detect rearrangements of the transcription factors FOS and FOSB in osteoid osteoma and osteoblastoma. Limitations in specificity and sensitivity remains with some osteosarcoma showing nuclear FOS expression and a small number of osteoblastomas lacking rearrangements. Aggressive appearing osteoblastomas and osteoblastoma-like osteosarcoma can be difficult to distinguish.

The guest, Dr. Daniel Baumhoer, discusses the potential use of methylation and copy number profiling in this setting. Osteoblastomas were found to be uniformly characterized by flat copy number profiles that can add certainty to their diagnosis.