Nike polo shirt stretch material runs small measure vintage European size

Nike women's golf polo shirt. Stretchy material -can't find material tag - feels soft and stretchy Tag size L -I bought this golf shirt years ago in France and their tag size L runs so much smaller than USA shirts Please measure!!! armpit to armpit about 17 - I would say it fits an average American size S to M women with a small bust middle of back to hem about 22.5.