Urine Cytology and Fluorescent In Situ Hybridization of Upper Urinary Tract Malignancies: A Report of Cases and Literature Review
Christopher A Lum, Christopher Gima, Ricky Kaneshiro, Eiji Matsubara, David Wei, Riruke Maruyama, Pamela Tauchi-Nishi. Queens Medical Center/Hawaii Pathologists Laboratory/University of Hawaii, Honolulu, HI; Showa University Northern Yokohama Hospital, Yokohama, Japan; Queens Medical Center, Honolulu, HI; Shimane University, Izumo, Japan
Background: Primary upper urinary tract urothelial carcinoma comprises approximately 5% of all urothelial cancers and 7-8% of renal tumors. Compared to its bladder counterpart, these malignancies present diagnostic challenges that may effect delays in detection, resulting in advanced stage at diagnosis with worsened prognosis. In this study, we investigate the utility of cytologic examination and UrovysionTM FISH in identifying these upper tract malignancies.
Design: A retrospective review of our database revealed 376 patients during the period of April 2008 to March 2011 with biopsy proven urothelial cancers. Fifty-nine (16%) of these patients were diagnosed with ureteral or renal pelvis primaries. During this same period, 325 patients underwent 443 UroVysionTM FISH studies with 202 concomitant cytologic exams.
Results: Twenty of the 376 urothelial cancer patients were had prior positive FISH results. Six (30%) had upper urinary tract malignancies with 9 of 13 FISH exams positive (sensitivity 69.2%). Sixteen of 30 cytologic studies revealed abnormal cells (sensitivity 53.3%). For voided urine specimens, FISH sensitivity (83.3%) exceeded cytology (21.4%). Combined cytology and FISH testing yielded a higher predictive value (sensitivity 83.3%). No false positive cytologic or FISH exams were observed.
FISH testing proved more sensitive for high grade (75.0%) than low grade tumors (60.0%). Low grade carcinomas demonstrated a higher percentrage homozygous 9p21 loss, while high grade malignancies showed 4 or more chromosomal gains per cell.
Our review revealed 4 patients with renal cell carcinomas. Tumor size had no bearing on FISH positivity, and none involved the renal pelvis. Both cases exhibited polysomy for chromosomes 3, 7, and 17; no homozygous 9p21 loss was noted. There were no discernible differences in karyotypic abnormalities between urothelial and renal cell carcinomas.
Conclusions: UrovysionTM FISH contributed to the diagnosis of upper tract malignancies, and demonstrated higher sensitivity than cytology, especially in the setting of voided urine specimens. Combined cytology and FISH testing yielded enhanced cancer identification. UrovysionTM FISH may also prove useful as an adjunct in the detection of renal cell carcinomas, and further studies may be warranted.
Category: Genitourinary (including renal tumors)
Wednesday, March 21, 2012 1:00 PM
Poster Session VI # 157, Wednesday Afternoon