Casas was born and raised in El Paso, Texas.[3] She attended Arizona State University, where she studied voice performance, and later received a bachelor's degree from the University of Texas at El Paso (UTEP) in communications.[2]
In 1986, she was working at KDBC, where she "spearheaded the Texas Breast Cancer Screening Project."[4] Casas starting anchoring on KVIA-TV with Gary Warner in 1993.[1] Casas has publicly and candidly shared medical procedures she underwent, including having a mammogram on television in 1993,[4] and documenting her own experience with thyroid disease in 2010.[5]
On January 7, 2020, Casas left her position at KVIA to work for the UMC Foundation.[6]