Shares of medical technology company Affymetrix ( AFFX) gained more than 12% Monday after the company said it expects fourth-quarter revenue to exceed analysts' expectations. The company says it should report sales of $100 million, compared with $99.47 million expected by analysts surveyed by Thomson First Call. "During the fourth quarter, we delivered important new products to customers and announced several exciting commercial agreements," said CEO Stephen Fodor. "It was a quarter of solid performance." Shares rose $2.46 to $24.18.