T1 Intensity: An Indication of 1p 19q Deletion in Oligodendroglial Neoplasms

Carolyn Branecky¹, Devyani Bedekar², Kathleen Schmainda³

Tumor genotype is becoming increasingly influential in guiding the treatment of brain tumors. Allelic losses on 1p and 19q have an incidence of 60-90% in oligodendroglioma cases1,2. It has been found that tumors displaying the 1p 19q co-deletion are more responsive both to radiation and chemotherapy and have a longer overall survival3,4. It would be highly beneficial for oncologists to have an indication of deletion status via imaging in cases where biopsy is not preferable. It has been found that 1p 19q deleted oligodendrogliomas tend to have a mixed intensity signal on T1 and that 1p 19q intact oligodendrogliomas and oligoastrocytomas have greater T1 signal homogeneity5,6. In this study we aim to find an imaging characteristic that is more readily apparent and quantifiable in order to allow for easy identification of tumors with 1p 19q deletion status.