The $350M question: Does postprostatectomy IMRT deliver?

Use of IMRT to treat prostate cancer, which carries a reimbursement rate approximately 50 percent higher than conformal radiotherapy (CRT), skyrocketed from zero in 2000 to 82.1 percent in 2009 among postprostatectomy patients. Despite the swift uptake, IMRT may not provide morbidity benefits among these patients, according to a study published online May 20 in JAMA Internal Medicine.

Prostate cancer treatment sits near the top of the Institute of Medicine’s priority list for comparative effectiveness research, partially because the costs of new technologies in prostate cancer have added $350 million to the annual healthcare tab in the U.S.

Previous research has indicated that IMRT is associated with lower gastrointestinal morbidity and improved cancer control compared with CRT because it reduces the radiation dose to adjacent organs. However, these benefits may not apply to all patients, according to Gregg H. Goldin, MD, from the department of radiation oncology at the University of North Carolina at Chapel Hill, and colleagues.

In the postprostatectomy setting, the radiation dose is lower than for primary treatment. “Therefore, the potential benefit of IMRT vs. CRT in terms of reducing treatment-related morbidity may be less pronounced.”

Goldin and colleagues sought to evaluate that hypothesis by comparing the morbidity and cancer control outcomes of IMRT vs. CRT using the Surveillance, Epidemiology, and End Results (SEER) Medicare-linked database.

The researchers identified 457 men who received IMRT and 557 who received CRT between 2002 and 2007 and examined gastrointestinal morbidity, urinary incontinence, nonincontinence urinary morbidity and sexual dysfunction. They also examined disease recurrence.

Postprostatectomy use of IMRT vs. CRT swelled from zero in 2000 to 82.1 percent in 2009. However, Goldin et al did not detect significant morbidity or recurrence differences between the two groups.

The researchers acknowledged the rapid development and adoption of newer surgical and radiation treatments “without (or before) proven benefit relative to older treatments.” They noted that physicians may have adopted IMRT because of anticipated morbidity reductions or higher reimbursement.

“Our study shows that these expectations may not be based in clinical reality.” Goldin and colleagues surmised that the lower dose in postprostatectomy patients reduced need for an advanced method to limit dose to nearby organs, which obviated the morbidity benefits of IMRT. “Although IMRT for the primary treatment of prostate cancer has a strong theoretical basis, the rationale for its use in the postprostatectomy setting is less compelling because a lower dose is used.”

The study, continued the researchers, “is broadly illustrative of a difficulty in health care in which new technologies are rapidly adopted before evidence of clinical superiority.”

For more about prostate cancer and comparative effectiveness, please read “Prostate Cancer: In the Eye of the Storm,” in Health Imaging.