The top after-market NYSE gainers Monday were Express, Radioshack Corp, Ruckus Wireless, ITT Educational and Flowers Foods, Inc. The top after-market NYSE losers were STMicroelectronics, Under Armour, Office Depot, Nordic American Tankers and hhgregg.

Gainers

Express, Inc. (NYSE:EXPR) shares climbed 13.51 percent to $15.96 in post-market trading. The company raised its fiscal 2012 earnings outlook to a range of $136 million to $138 million or $1.56 to $1.59 per share from its prior estimation of $128 million to $133 million or $1.47 to $1.53 per share.

Radioshack Corp. ((NYSE:RSH) shares surged 5.19 percent to $2.43 in post-market trading. The company announced Monday the end of its relationship with Target, where it helps operate Target Mobile in 1,500 Target stores, effective Apr. 8, 2013.

Ruckus Wireless, Inc. (NYSE:RKUS) shares gained 2.26 percent to $22.20 in post-market trading. The stock has a 52-week low of $12.25, a 52-week high of $23.80 and $1.60 billion in market capitalization.

ITT Educational Services, Inc. (NYSE:ESI) shares rose 2.23 percent to $14.70 in post-market trading. The stock has a 52-week low of $14.13, a 52-week high of $77.00 and $335.41 million in market capitalization.

Flowers Foods, Inc. (NYSE:FLO) shares gained 1.80 percent to $27.71 in post-market trading after climbing more than 9 percent in regular trading.

Losers

STMicroelectronics N.V. (NYSE:STM) shares slumped 4.82 percent to $7.50 in post-market trading. The stock has a 52-week low of $4.51, a 52-week high of $8.60 and $7.0 billion in market capitalization.

Under Armour, Inc. (NYSE:UA) shares plunged 2.28 percent to $47.24 in post-market trading. The stock has a 52-week low of $35.88, a 52-week high of $60.96 and $5.06 billion in market capitalization.

Office Depot, Inc. (NYSE:ODP) shares fell 1.51 percent to $3.74 in post-market trading. The stock has a 52-week low of $1.51, a 52-week high of $3.84 and $1.08 billion in market capitalization.

Nordic American Tankers Ltd. ((NYSE:NAT) shares declined 1.33 percent to $8.93 in post-market trading.

hhgregg, Inc. (NYSE:HGG) shares declined 1.18 percent to $7.35 in post-market trading. The company lowered its fiscal 2013 earnings guidance to a range of $0.70 to $0.80 per share from its prior estimation of $0.90 to $1.05 per share. Currently, hhgregg expects full year net sales increase from flat to 1 percent, down from the previous guidance of net sales increase of 3.0 to 6.0 percent.