International Game Technology ( IGT) shares tumbled Thursday after the slot machine maker's first-quarter profit showed up a bit light despite record revenue. Income from continuing operations rose 5% to $122.4 million, or 33 cents a share, vs. $116.7 million, or 32 cents a share, in the prior-year quarter. Revenue hit a record $641.2 million, as the company posted record machine sales of 55,300. Analysts expected the company to earn $126.7 million, or 33 cents a share, on revenue of $612.7 million. The year-ago quarter included income from discontinued operations related to the sale of IGT's OnLine Entertainment Systems. "We saw strong operating cash flows during the quarter at IGT," the company said. "Our results demonstrate that despite a slowdown in domestic machine demand, we continue to execute on our strategy to grow the profitability of our international business and our efforts to expand the contribution from non-machine product sales." Shares fell $2.55, or 7.6%, to $31.