Kellas began his distinguished career with B.A. and B.S. degrees from West Virginia University, where he was a member of the Phi Beta Pi fraternity. He served as Medical Director of the Wheeling Hospital from 1959-1982 and as Director of the Family Practice Residency Program from 1977-1987. He was elected as a member of honor into the prestigious George A. Piersol Anatomical Society of the University of Pennsylvania.