** Shares of restaurant chain Wingstop WING.O rise 9.1% to $251.33

** Co posts 15.7% increase in Q1 system-wide sales of $1.3 billion, exceeding analysts' average estimate of $1.20 billion, according to data compiled by LSEG

** Co reports Q1 adj. net income of $28.32 million versus analysts' estimate of $24.33 million

** Including session's moves, WING stock down 12.2% YTD

(Reporting by Padmanabhan Ananthan)

((Padmanabhan.Ananthan@thomsonreuters.com))