The growing scarcity of sterile, injectable drugs is one of the biggest issues confronting hospitals across the country, and will be a key issue at the annual American Society of Clinical Oncology meeting in Chicago this weekend. Health officials blame the shortages on industry consolidation that has left only a handful of generic manufacturers of these drugs, even as the number of drugs going off-patent is growing. Some drugmakers have been plagued by manufacturing problems that have shut down multiple plants or production lines, while others have stopped producing a treatment when profit margins erode too far.