A concert with thousands of fans turned into an intimate moment between Garth Brooks and one woman with cancer.While singing his song "The Dance" Friday night in Minneapolis, the country star noticed a fan with a very touching sign. It read, "Chemo this morning. Garth tonight. Enjoying 'The Dance'."Brooks decided he wanted to keep the sign, so--after serenading the fan--he made a trade.The fan was Teresa Shaw of Iowa, who felt well enough to make the drive for a much-deserved break from treatment for her stage three breast cancer. In addition to the guitar, Brooks also gave Shaw a kiss and emotional words of encouragement."You have all my strength. You have everybody's strength in here," said Brooks, whose mother and sister died of cancer.Another fan posted the video on YouTube, where it has more than half a million views.