Dendreon (NASDAQ: DNDN) is posting another day of impressive gains, and with today's high-single-digit move, the stock has gained about 75% from its early November lows. That's not to say things are looking great for the company  -- all it takes is a glance at the stock price from early 2011 to remember just how far the maker of prostate cancer treatment Provenge has fallen. But as Brenton Flynn outlines in the video below, there's likely one simple explanation for the outsized gains we've seen over the past 90 days.