Yes, LANCETS is a Scrabble word!

Letter values in Scrabble US: L 1, A 1, N 1, C 3, E 1, T 1, S 1.

Is it a valid word?

LANCETS is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

an acutely pointed Gothic arch, like a lance
a surgical knife with a pointed double-edged blade; used for punctures and small incisions

Also: lancet arch.