When young men with blood in urine also have side pain, looking inside the ureter with a scope found cancer in one out of two cases—even though the CT scan showed nothing wrong.
Scientific Claim
In men under 40 with high-grade microscopic hematuria and flank pain, uretroscopy detected carcinoma in situ in one of two cases despite normal CT imaging, indicating that ureteral malignancy may be missed by imaging alone and requires direct visualization when symptoms suggest ureteral involvement.
Original Statement
“Unilateral uretroscopy for the 2 cases presented with pain detected carcinoma in situ in one of them... Right uretroscopy... marked erythema was found in the ureteric wall... Pathology showed positive urine cytology and CIS of the ureter.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The claim describes an observed event in a small subgroup without implying generalizability or causation. The language correctly reflects the observational nature and limited sample.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Prospective Cohort StudyLevel 2bThe proportion of young men with hematuria and flank pain who have ureteral malignancy missed by CT but detected by uretroscopy.
The proportion of young men with hematuria and flank pain who have ureteral malignancy missed by CT but detected by uretroscopy.
What This Would Prove
The proportion of young men with hematuria and flank pain who have ureteral malignancy missed by CT but detected by uretroscopy.
Ideal Study Design
A prospective cohort of 200 men under 40 with ≥25 RBC/HPF, normal CT, and flank pain, all undergoing both CT and uretroscopy; primary outcome: detection rate of ureteral malignancy by uretroscopy despite negative CT.
Limitation: Cannot determine if uretroscopy improves survival or is cost-effective.
Case-Control StudyLevel 3bWhether flank pain is more strongly associated with ureteral malignancy than other symptoms in young men with hematuria.
Whether flank pain is more strongly associated with ureteral malignancy than other symptoms in young men with hematuria.
What This Would Prove
Whether flank pain is more strongly associated with ureteral malignancy than other symptoms in young men with hematuria.
Ideal Study Design
A case-control study comparing 50 young men with ureteral CIS to 100 with other urologic conditions, assessing prevalence of flank pain and prior CT results.
Limitation: Cannot establish incidence or predict risk prospectively.
Cross-Sectional StudyLevel 3cThe prevalence of ureteral lesions in young men with hematuria and flank pain undergoing uretroscopy.
The prevalence of ureteral lesions in young men with hematuria and flank pain undergoing uretroscopy.
What This Would Prove
The prevalence of ureteral lesions in young men with hematuria and flank pain undergoing uretroscopy.
Ideal Study Design
A cross-sectional study of 150 men under 40 with hematuria and flank pain, all undergoing uretroscopy after normal CT; primary outcome: detection rate of ureteral abnormalities.
Limitation: Cannot determine if findings are causal or predictive.
Evidence from Studies
Supporting (1)
High-grade microscopic hematuria in adult men can predict urothelial malignancy.
In young men with blood in urine and back pain, even if scans look normal, a scope test inside the ureter found cancer in one out of two cases — proving scans can miss it and you need to look directly inside.