Even it has 1 confirmation, some exchanges don't credit it to your account, if they require like 2, 3 or 4 confirmations and with only 1 confirmation they will show that deposit as Pending, or In progress. Some exchanges can show a not confirmed deposit as Pending but not all exchanges have this policy.
Does that really matter in this case since OP confirms that his transaction is pending anyway (I assume from this wallet/block explorer)? Without checking his exchange balance he should be able to tell whether he can "cancel" his transaction or not from that. CMIIW.
Speaking of that, exchanges that I've used so far use some random range such as 1-3 confirmations before my wallet balance is updated, it can be annoying sometimes.