Despite the good news about experimental cancer drugs, the mainstays of chemotherapy are in short supply at hospitals around the country. Medications such as leucovorin, cytarabine, cisplatin and doxorubicin are essential for treating a number of different types of cancer. These drugs are sold in generic form with low profit margins, so manufacturers lack a strong incentive to correct the shortages. As a result, doctors are having to hunt down alternatives. But for some cancers, there are no good alternatives. When this happens, patients may have to delay their treatments. This situation is dangerous, but there does not seem to be a solution in sight.