Significance of tissue fragments in voided urine specimens.
OBJECTIVE
To determine the diagnostic significance of tissue fragments in voided urine specimens.


METHODS
We reviewed all the voided urine specimens collected and processed by the Millipore filter technique (Bedford, Massachusetts, U.S.A.) at our institution between January 1, 1997, and December 31, 1998, and the corresponding biopsies obtained within 120 days after urine examination. The type and number of tissue fragments were correlated with the histologic diagnosis and clinical features; the results were compared to those from a recently published study.


RESULTS
Of the 2,553 voided urine specimens examined, 174 (7%) had corresponding biopsies. Cell groups (tissue fragments) consisting of either flat sheets or three-dimensional structures were significantly more common (57%) (chi 2 P < .005) in urine specimens with biopsies revealing urothelial malignancies than in negative biopsies (6%). Three-dimensional groups were also statistically more common in cases with invasive transitional cell carcinoma. Proper identification of tissue fragments was highly significant and correlated with urothelial neoplastic changes.


CONCLUSIONS
The results of the present investigation using the Millipore filter technique for voided urine cytology processing, differed from those of a recently published study that employed cytocentrifugation. Tissue fragments, to be differentiated from groups, clumps or clusters that often result from centrifugation and other concentration artifacts, were strongly associated with urothelial neoplasia, uncommonly with nonneoplastic disease processes affecting the urinary tract but always with urothelial disease.
Cytopathology and Cytometry Section, Department of Pathology and Laboratory Medicine, University of Pennsylvania Medical Center, 3400 Spruce Street, 6 Founders Pavilion, Philadelphia, Pennsylvania 19104, USA. jfnasuti@mail.med.upenn.edu
J F
JF
Nasuti
S R
SR
Fleisher
P K
PK
Gupta
D000328:Adult; D000368:Aged; D001706:Biopsy; D002295:Carcinoma, Transitional Cell / Q000473:pathology* / Q000652:urine*; D005260:Female; D005374:Filtration; D006801:Humans; D008297:Male; D008851:Micropore Filters; D008875:Middle Aged; D014556:Urine / Q000166:cytology; D014571:Urologic Neoplasms / Q000473:pathology* / Q000652:urine*