For elderly cancer patients, 5 year Medicare costs in 2004 were approximately $21.1 billion.
Yabroff, Robin, Elizabeth Lamont, Angela Mariotto, Joan Warren, Marie Topor, Angela Meekins, and Martin Brown. Cost of Care for Elderly Cancer Patients in the United States. J Natl Cancer Inst. 2008; 100(9): 630-41. https://academic.oup.com/jnci/article/100/9/630/911739/Cost-of-Care-for-Elderly-Cancer-Patients-in-the