Use of a Test Diet in Screening for Neuroblastoma Reduces False‐Positives Attributable to Food Intake

Abstract

We attempted to reduce false-positives during screening for neuroblastoma using a qualitative urine test by introducing a test diet without foodstuffs known to cause false-positive results. In preliminary in-vivo experiments, intake of contra-indicated foods such as orange juice or banana was shown to result in high percentages of false-positive results several hours after food intake. False-positive results were obtained even after 24 hours among breast-fed infants whose mothers received orange juice. In a controlled field trial the false-positive rate was reduced to 2.84% among 540 infants taking the test diet compared with 5.05% among 9,844 control infants following conventional guidance on contra-indicated foods (p less than 0.05). For comparison, a questionnaire survey of nationwide screening in Japan in 1987 revealed that 66% of the screening centres employed qualitative urine tests, either a Spot or Dip method. False-positive rates, including those due to inappropriate urine collection, ranged from 0.4% to 33.7% (mean 7.1%). Rates ranged from 0.2% to 18.7% (mean 3.4%) in the remaining 34% of screening centres employing a quantitative method with high performance liquid chromatography.

Extra-endocrine phenotypes at infancy in multiple endocrine neoplasia type 2B: A case series of six Japanese patients

“…At the time of the present assessment, the patients (3 males and 3 females) had a median age of 23 (range: 14-31) yr. The median age at MEN2B diagnosis, as determined by cervical masses, oral lesions, enteritis, and other symptoms (Supplementary Table 1), and the time point at which patients underwent thyroidectomy for MTC was 11 (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) yr. Patient characteristics are summarized in Table 1.…”

“…From 1984 to 2003, neuroblastomas were screened at approximately 6 mo postpartum in 77-86% of all births in Japan, revealing a cumulative incidence of 1.37-1.99 per 100,000 births on mass screening (15). The mean frequency of false positives, including those attributed to inappropriate urine collection, was approximately 7.1 and 3.4% by qualitative and HPLC testing, respectively (16). In the present study, no patients consumed any food at the time of testing, which could have resulted in a false-positive result.…”