Government researchers reported that Medicare costs for treating cancer patients which are 65 or older, over a period of five years comes with an estimated bill of $21.1 billion, a figure which is expected to skyrocket as baby boomers become seniors. Experts at the National Cancer Institute in Bethesda, Maryland have published a study in the Journal of the National Cancer Institute.

The cost varies, as expected, with the type of cancer and the period of treatment. Lung, colorectal and prostate tumors have the highest price tag, and the most expenses are incurred in the first 12 months of treatment and in the last 12 months of life. Individually, brain and other nervous system cancers were the most costly for men while or women, ovarian cancer was the most expensive for overall phases.

The research relies on 1999-2003 data from more than 700,000 cancer patients covered by Medicare and produced figures for people diagnosed with cancer in 2004. The cancer patients were compared with more than 1.6 million patients who did not develop cancer to determine net cancer costs.

"Because the U.S. population is aging and growing, we think that these costs are going to get higher in the future," said lead researcher Robin Yabroff, an epidemiologist at the U.S. National Cancer Institute, as quoted by The Washington Post. "We think there are going to be a lot more cancer patients in the future," he said.

In 2003, when the last data was used, there were about 10 million Americans living with cancer. In the following year, the United States spent $72.1 billion for cancer care.