Prostate cancer patients choose among multiple treatments that are often considered equally appropriate but can have different risks and side effects. The treatments can also vary in cost, with IMRT being one of the most costly options. Cancer of the prostate—a gland located at the base of the urinary bladder—is the second most common cancer among men in the United States, with approximately 1 in 6 men receiving a diagnosis of prostate cancer in his lifetime. In 2010, there were an estimated 218,000 new cases of prostate cancer and approximately 32,000 deaths due to prostate cancer. Most men in the United States are diagnosed with prostate cancer as a result of an abnormal digital rectal exam or prostate- specific antigen test. After an abnormal test result, beneficiaries often undergo a prostate biopsy, during which a provider—typically a urologist—removes small amounts of prostate tissue. Another provider then examines the tissue to determine whether a beneficiary has prostate cancer. IMRT is one of multiple treatment options available to patients with prostate cancer. The type of treatment a prostate cancer patient chooses depends on a number of different factors such as life expectancy, overall health, personal preferences, provider recommendations, and the clinical characteristics of a patient’s prostate cancer. For many men, multiple treatment options are considered equally appropriate. For instance, IMRT, brachytherapy, and a radical prostatectomy are all among the treatments considered appropriate for men with low-risk prostate cancer. Even though such treatments are often considered equally appropriate, the risks and side effects for each treatment are different. Compared to IMRT, prostate cancer patients undergoing a radical prostatectomy have a higher rate of short term urinary problems and erectile dysfunction but do not face bowel-related side effects, which are experienced by some men undergoing IMRT. Compared to IMRT, prostate cancer patients undergoing brachytherapy have lower rates of bowel-related side effects but about 1 in 10 patients undergoing brachytherapy experience acute urinary retention. Also, several studies have reported that physician recommendations play a large role in influencing a patient’s decision, and another study found that the use of a particular prostate cancer treatment decreased after its payment was reduced, suggesting that financial incentives may have influenced treatment decisions.are generally not required to disclose to their patients that they have a Currently, providers who self-refer IMRT services financial interest in the service.treatments are summarized in table 1. Medicare reimbursement rates for IMRT delivery services varied over time, and rates are not directly comparable between settings. Beneficiaries receive approximately 45 separate IMRT delivery services over several weeks during a course of IMRT to treat prostate cancer. Medicare beneficiaries predominantly receive IMRT delivery services in two settings—physician offices or hospital outpatient departments. The Medicare reimbursement per IMRT delivery service increased from approximately $319 to $421 from 2006 to 2010 and then to $484 by 2013 for services performed in hospital outpatient departments. For services performed in physician offices, the reimbursement rate decreased from approximately $690 to $511 from 2006 to 2010 and then to $406 by 2013. The reimbursement rates for IMRT delivery services performed in physician offices and hospital outpatient departments are not directly comparable. For instance, if an IMRT delivery service was performed in a hospital outpatient department, payment includes the technical component for image guidance, which is almost always furnished with an IMRT service. In physician offices, image guidance is reimbursed separately. Researchers have consistently found that courses of IMRT, which include IMRT delivery and other services, are more costly than other treatments for prostate cancer, with the exception of proton therapy. Researchers have found IMRT to be more costly despite differences among studies in design and methodology, such as the services counted toward total treatment costs, the duration of time during which costs are studied (e.g., first year costs vs. lifetime costs), and the patient population studied. One recent study found that, among men diagnosed with prostate cancer in 2005, the cost to Medicare per course of treatment was approximately $14,000 to $15,000 higher for men receiving IMRT ($31,574) than for men who received brachytherapy ($17,076) or a prostatectomy ($16,469 or $16,762, depending on the type of prostatectomy). Despite the 2013 reduction in the Medicare reimbursement rate for IMRT delivery services performed in physician offices, we found that IMRT remains substantially more expensive than other treatments for prostate cancer, with the exception of proton therapy. We found that the number of and expenditures for Medicare prostate cancer–related IMRT services performed by self-referring groups grew rapidly from 2006 through 2010. In contrast, the number of and Medicare expenditures for prostate cancer–related IMRT services performed by non-self-referring groups declined over the period. From 2006 through 2010, the number of prostate cancer–related IMRT services performed by self-referring groups increased rapidly, while the number performed by non-self-referring groups decreased. The number of prostate cancer–related IMRT services performed by self-referring groups increased from approximately 80,000 to 366,000, an annual growth rate of 46 percent (see fig. 1). Consistent with that growth, the number of self-referring groups also increased rapidly over the period. In contrast, the number of prostate cancer–related IMRT services performed by non-self-referring groups in physician offices decreased from approximately 490,000 to 466,000, an annual decrease of 1 percent. The rapid increase in prostate cancer–related IMRT services performed by self-referring groups coincided with several other trends from 2006 through 2010. First, the number of prostate-cancer related IMRT services performed in hospital outpatient departments and by self-referring and non-self-referring groups all grew from 2006 to 2007. After 2007, the rapid increase in prostate cancer–related IMRT services performed by self- referring groups coincided with declines in these services within hospital outpatient departments and among non-self-referring groups. Overall utilization of prostate cancer–related IMRT services therefore remained relatively flat across these settings after 2007, indicating a shift away from hospital outpatient departments and non-self-referring groups and toward self-referring groups. (See app. II for information on the trends in IMRT services performed in hospital outpatient departments.) Second, while the number of prostate cancer–related IMRT services provided to Medicare fee-for-service (FFS) beneficiaries has stabilized since 2007, the percentage of newly diagnosed Medicare beneficiaries receiving IMRT has increased. While seemingly contradictory, these two trends occurring simultaneously can in part be explained by (1) a decrease in the total number of Medicare FFS beneficiaries from 2006 through 2010 and (2) a decrease in the number of men newly diagnosed with prostate cancer. Third, the increasing percentage of prostate cancer patients receiving IMRT may partially be explained by a shift from an older form of EBRT—3D-CRT—to a newer form—IMRT, though the largest effect of this substitution likely occurred earlier in our study period as IMRT largely replaced 3D-CRT by 2007. In 2010, urologists performed approximately 89.1 percent of office visits billed under limited-specialty groups, compared to 5.7 percent for multispecialty groups. Additionally, the average number of specialties that billed office visits under limited-specialty groups in 2010 was 3.3, compared to 36.2 for multispecialty groups. 56,000 to 343,000. In contrast, the number of such services performed by multispecialty self-referring groups, which were comprised of a large number of different provider types, declined slightly, going from approximately 23,000 to 22,000. Medicare expenditures for prostate cancer–related IMRT services performed by self-referring groups increased rapidly from 2006 through 2010, while decreasing for services performed by non-self-referring groups. Specifically, expenditures for prostate cancer–related IMRT services performed by self-referring groups increased from $52 million to $190 million, an average increase of 38 percent a year (see fig. 3). In contrast, expenditures for prostate cancer–related IMRT services performed by non-self-referring groups in physician offices declined by an average of 8 percent a year. For comparison, expenditures for prostate cancer–related IMRT services performed in hospital outpatient departments grew an average of 7 percent a year during the period we studied. (For more information about hospital outpatient department expenditure trends, see app. II.) Self-referring providers were more likely to refer their Medicare prostate cancer patients for IMRT and less likely to refer them for other treatments when compared to non-self-referring providers. In addition, after providers began self-referring IMRT services, they substantially increased the percentage of their prostate cancer patients they referred for IMRT, in contrast to providers who did not begin to self-refer IMRT services during the same period. Self-referring providers were more likely to refer their prostate cancer patients for IMRT and less likely to refer them for other treatments compared to non-self-referring providers. Self-referring providers referred approximately 52 percent of their patients who were newly diagnosed with prostate cancer in 2009 for IMRT, while non-self-referring providers referred 34 percent of their patients for IMRT (see table 2). Self-referring providers also referred a lower percentage of their prostate cancer patients for nearly all other types of treatments compared to non-self- referring providers, with the largest differences among patients being referred for brachytherapy or a radical prostatectomy. Other differences were smaller—self-referring providers were about 8 percent less likely to refer their patients for active surveillance compared to non-self-referring providers. (For alternative groupings in which beneficiaries are sorted into discrete treatment categories, see app. III.)