LHRH agonist use declines after reimbursement cuts

Medical castration has lost some ground as the preferred androgen deprivation treatment for prostate cancer, while use of surgical castration has increased slightly, according to researchers from the Cleveland Clinic. Financial considerations are most likely the driving force behind this shift in treatment trends, they stated.

For this retrospective study published in Cancer (112[10]:1-7, 2008), J. Stephen Jones, MD, and colleagues hypothesized that a 50% reduction in reimbursement for LHRH agonists, as mandated by the Medicare Modernization Act (MMA) of 2003, changed the way practitioners approach medical and surgical castration.

They mined data for patients 65 and older from the Medicare Part B Extract Summary System from 2001 to 2005, focusing on several codes (see Table).

Between 2001 and 2003, LHRH ag-onist use increased; orchiectomy rates decreased between 2001 and 2004. However, from 2004 to 2005, there was a sharp downward spike in the use of LHRH agonists, but an increase in orchiectomies.

During the study time period, there was a marked shift in Medicare payment: In 2003, a little over $973 million was spent on LHRH agonists vs $1.6 million in surgeon’s fees for castration. After the MMA went into effect, payment for LHRH agonists dropped by 64% to about $355 million, while the average payment for surgical castration increased by 7%.

Overall, “total expenditures for combined medical and surgical castration decreased 63% from $1.2 billion in 2003 to $450 million in 2005,” they wrote.

They offered several possible reasons for this shift such as early detection of less aggressive disease not requiring androgen deprivation, use of longer acting antiandrogen agents, and changing attitudes toward surgical castration. Ultimately, the group said that the dip in popularity of medical castration coincided too closely with reimbursement changes.

They pointed out that among the LHRH agonists, there was actually an increase in the use of triptorelin(Drug information on triptorelin) pamoate (Trelstar). Of all agents, this was the only one to maintain its pre-MMA reimbursement rate at about $228 per dose.

“Although correlation does not prove causation, these data contain a clear trend, which suggests that financial pressures most likely contributed to prescription practice of androgen ablation among practitioners in a U.S. Medicare population,” the group concluded.

In an accompanying Cancer editorial, Gerald Chodak, MD, noted that the increase in orchiectomy did not completely offset the drop in LHRH usage, which “argues against economics as being the sole explanation for this change.” Dr. Chodak is the director of the Midwest Prostate and Urology Health Center in Chicago.

He suggested that nonmonetary factors, such as a greater understanding among urologists that not all patients benefit from androgen deprivation, may have directed the trend. He did not rule out lower reimbursement, since physicians cannot be expected to sustain monetary losses in order to treat patients, but said there is no evidence that patients are being switched from medical to surgical castration solely for financial gain.