Value of Reflex ImmunoCyt Testing for the Diagnosis of Bladder Cancer
Anna B Berry, Anobel Y Odisho, Ardalan E Ahmad, Matthew R Cooperberg, Peter R Carroll, Badrinath R Konety. University of California San Francisco, San Francisco, CA; University of Minnesota, Minneapolis, MN
Background: An atypical diagnosis in voided urine cytology poses a dilemma for the clinical team, and frequently leads to cystoscopy, or other additional testing, to rule out the presence of tumor. ImmunoCyt, a triple immunofluorescent antibody assay, is an FDA cleared voided urine test for antigens associated with urothelial carcinoma (UC). While the test is designed to be used as a reflex test for atypical voided urine cytology, and can be employed by any fully functional cytology laboratory, few practices are currently using it in this way. We reviewed the initial outcomes for patients undergoing ImmunoCyt reflex testing at our institution to determine the usefulness of the test in determining the need for cystoscopic examination. the need for cystoscopy.
Design: The ImmunoCyt (uCyt) assay is performed at our institution reflexively on all voided urine cytology tests read as atypical. Subsequent patient workup, such as cystoscopy, biopsy, and follow up is currently at the discretion of the treating urologist. We retrospectively reviewed patients tested between January 2007 and June 2010. We examined medical records to determine patient history and the outcomes of subsequent cystoscopy, which was considered pertinent if performed within 90 days of the uCyt assay.
Results: Reflex uCyt testing was performed on 595 atypical voided urine samples from 324 patients, 506 of which were followed by cystoscopy within 90 days. Of the 595 samples, 441 (74%) were from patients with a history of UC. 142 samples (24%) were from patients with hematuria and no history of UC. Using cystoscopy within 90 days as a reference, reflex uCyt testing of samples with a history of UC showed a sensitivity and specificity of 73% and 49%, respectively, a negative predictive value (NPV) of 80% and positive predictive value (PPV) of 37%. In 159 samples with a history of low grade UC, reflex uCyt had a sensitivity of 75%, specificity of 50%, NPV of 82% and PPV of 39%, while in 221 assays in those with a history of high grade UC, it had a sensitivity of 74%, specificity of 44%, NPV of 79%, and PPV of 37%. With no prior history of UC, reflex uCyt had a sensitivity of 85%, specificity of 59%, NPV of 94% and PPV of 33%.
Conclusions: When used as a reflex test on atypical urine cytology a negative uCyt result can effectively be used to predict a negative cystoscopy. In those with a history of low grade UC, negative reflex uCyt can be used to obviate.
Category: Genitourinary (including renal tumors)
Wednesday, March 21, 2012 1:00 PM
Poster Session VI # 156, Wednesday Afternoon