Cystoscopy plus renal ultrasound is the most cost–effective approach for the initial diagnostic evaluation of patients with asymptomatic microscopic hematuria (AMH), according to a new analysis online today in JAMA Internal Medicine.

AMH is common and may signal occult cancer in the genitourinary system, but guidelines vary and few studies have looked at the cost–effectiveness of AMH evaluation, say the researchers led by Dr. Joshua Halpern of Weill Cornell Medicine in New York City.

Using a decision–analytic model with relevant inputs from the medical literature, they estimated the relative cost per cancer detected for four common diagnostic approaches for the evaluation of AMH, “with particular focus on the radiodiagnostic component, because this is the source of greatest morbidity, cost, and controversy,” they note.

The four approaches were computed tomography (CT) alone; cystoscopy alone; CT plus cystoscopy; and renal ultrasound plus cystoscopy.

CT alone detected 221 cancers at a cost of $9.3 million dollars. Ultrasound and cystoscopy detected 245 cancers and was most cost–effective, with an incremental cost per cancer detected (ICCD) of $53,810. Replacing ultrasound with CT detected only one additional cancer at an ICCD of about $6.5 million, “which is a lot of money for one cancer detected,” said Dr. Halpern in a JAMA podcast. Ultrasound and cystoscopy remained the most cost–effective approach in subgroup analysis.

In an editorial, Dr. Leslee Subak and Dr. Deborah Grady, University of California, San Francisco note that there is “no evidence from randomized clinical trials that detection, evaluation, and treatment of AMH results in prolongation of life, avoidance of death from urinary tract cancer, or improved quality of life.”

“As a primary care internist, I see a lot of (AMH) because there are a lot of urinalyses done for a variety of reasons,” Dr. Grady said in the podcast. “I want to make it clear that these urinalyses are not done for screening for urologic cancer and they should not be done for that purpose because there is no recommendation to screen for urologic cancer using urinalysis and in fact the U.S. Preventive Services Task Force recommends against that type of screening.”

Dr. Grady said the most important finding in this analysis is that the workup of AMH “should include renal ultrasound and cystoscopy and definitely should not include CT urography.”

That's because it's much more expensive, it exposes patients to radiation, and it requires contrast and patients can have contrast reactions, she explained. “And finally you find a whole lot more false positives when you are using CT as opposed to ultrasound and then those also need to be worked up.”

This analysis is important, write Dr. Subak and Dr. Grady, because it provides “useful data for national and international guideline groups as they reconsider recommendations, and for clinicians faced with making decisions about the evaluation of AMH. While cystoscopy plus renal ultrasound should be the preferred approach for initial evaluation, testing should be individualized based on shared decision making, patient characteristics, such as risk factors for genitourinary cancer, the results of prior evaluations, and patient preferences. The results of this cost–effectiveness analysis provide helpful data to improve high–value care.”

“Most groups are revising their guidelines every five to 10 years,” Dr. Subak said in the podcast. “There is a big push for healthcare value and that can affect guideline development so studies such as Dr. Halpern's are critical in providing especially the cost–effectiveness portion of the data that the guideline groups can use. Clinicians are looking for the best way to evaluate a finding of (AMH) and these results provide a very nice addition to existing guidelines on how to do that."

—Megan Brooks