Model finds CT scans for hematuria associated with secondary cancers, more cost

Hematuria evaluation may be optimized with risk stratification and more selective application of both diagnostic testing in general and CT imaging, according to a comparison of guidelines.

Using CT to evaluate all cases of hematuria was associated with risk of secondary cancers and a cost of more than $1 million per extra cancer case detected, according to a modeling study that compared existing guidelines.

Researchers developed a microsimulation model to assess the following guidelines on initial evaluation of hematuria: Dutch, Canadian Urological Association (CUA), Kaiser Permanente (KP), Hematuria Risk Index (HRI), and American Urological Association (AUA). They used a hypothetical cohort of 100,000 patients with hematuria who were 35 years of age or older from August 2017 through November 2018.

Under the Dutch and CUA guidelines, patients received cystoscopy and ultrasonography if they were age 50 years or older (Dutch) or age 40 years or older (CUA). Under the KP and HRI guidelines, patients received different combinations of cystoscopy, ultrasonography, and CT urography or no evaluation on the basis of risk factors. Under the AUA guidelines, all patients 35 years or older received cystoscopy and CT urography. Results were published July 29 by JAMA Internal Medicine.

A total of 3,514 patients had urinary tract cancers (estimated prevalence, 3.5%; 95% CI, 3.0% to 4.0%). Testing according to the AUA guidelines missed fewer cancer cases (82 [2.3%]) compared with the detection rate of the HRI (116 [3.3%]) and KP (130 [3.7%]) guidelines. However, the simulation model projected 108 (95% CI, 34 to 201) radiation-induced cases of cancer under the KP guidelines, 136 (95% CI, 62 to 229) under the HRI guidelines, and 575 (95% CI, 184 to 1,069) under the AUA guidelines per 100,000 patients. The CUA and Dutch guidelines missed a larger number of cancer cases (172 [4.9%] and 251 [7.1%]) but were not associated with any cases of radiation-induced secondary cancer.

Evaluation following the AUA guidelines cost approximately double the other four guidelines, with an incremental cost of $1,034,374 per case of urinary tract cancer detected compared with that of the HRI guidelines.

“Well-intentioned efforts may lead to the widespread dissemination of clinical practices before their safety and effectiveness are clearly understood,” the authors concluded. “This model-based comparison of 5 different guidelines for the diagnostic evaluation of hematuria suggests that, in addition to its substantial costs, the potential harms of the intensive application of uniform CT urography may outweigh the advantages of early diagnosis of urinary tract malignant neoplasms.”