Shares in Seattle's Dendreon Corp. plummeted 67.4 percent Thursday after it broke the news that sales of Provenge (sipuleucel-T) were lower than expected. Dendreon reported just $49.6 million in revenues for the prostate cancer vaccine, coming in $8 million lower than consensus estimates of $57.7 million. Dendreon attributed the miss to a lack of understanding among physicians about how to get reimbursed for Provenge, and expressed confidence that the recent positive National Coverage Determination (NCD) and assignment of a Q-code would enable increased adoption of the therapy over time.