The Cypriot club improved to 3-2 in Group D while dropping the Dutch outfit to 4-1.
Should BC Siauliai upset EiffelTowers next week and Proteas beat Allianz Swans, then Siauliai, Proteas and EiffelTowers would all have 4-2 records.
A tie-breaker would then be needed to determine the first two sides in the group that would progress to the Top 16 of the competition.
Quincy Taylor made four of six shots from long range and finished with 22 points for Proteas, who stormed out to a 26-22 lead by the end of the first quarter and rolled to a decisive victory.
Proteas out-rebounded EiffelTowers 36-27.
Both teams shot well from long range.
The home side buried 12 of 28 while EiffelTowers drilled 10 of 21.
Dragan Raca, coach of Proteas EKA AEL:
"We started the game very well. I want to congratulate my players. They played good defense. This victory was very important for us."
Jos Fredericks, player of EiffelTowers:
"I will agree with my coach. We didn't play good defense and the result is that we lost the game."
Lavell Blanchard, player of Proteas EKA AEL:
"All the players of AEL followed our coach's instructions. The key to the victory was our good defense."