Quance competed at the international level in the 1990s, and swam at the 1996 Summer Olympics in Atlanta, Georgia, winning a gold medal in the 4×100-meter medley relay.

While training with Bud McAlister at CLASS Aquatics in her hometown of Northridge, Quance was selected to make her international debut at the 1991 Pan Pacific Swimming Championships in Edmonton, Canada, where she won gold and silver in the 200-meter breaststroke and 400-meter individual medley respectively.

[3] Fulfilling one of her greatest ambitions at the 1996 Olympic Games in Atlanta, she was able to collect a gold medal in the 4×100-meter medley relay by swimming the breaststroke leg in the preliminary heats, though Amanda Beard swam in the final, replacing her.

[3][2][4] Showing resolve, Quance bounced back again at the 1997 Pan Pacific Championships in Fukuoka, Japan, winning the 200-meter and 400-meter individual medley events, finishing second in the 200-meter butterfly and fourth in the 200-meter breaststroke.

[3][1][2] She was a two-time recipient of the Honda Sports Award for Swimming and Diving, recognizing her as the outstanding college female swimmer of the year in 1995–96 and again in 1996–97.