Multi‐target fluorescence in situ hybridization in bladder washings for prediction of recurrent bladder cancer

Abstract

The objective of this study was to evaluate the diagnostic value of chromosomal analysis by fluorescence in situ hybridization (FISH) for predicting recurrence of urothelial carcinoma (UC) after transurethral resection. One hundred and thirty-eight patients (median age 68.5 years) with a history of UC were eligible for this prospective study. FISH was applied to cytospin specimens prepared from bladder washings taken during a negative control cystoscopy. The multi-target FISH test UroVysion 1 (Abbott/Vysis) containing probes to the centromeres of chromosomes 3, 7, 17 and the 9p21 locus was used. UC recurrence was defined as a positive biopsy during follow-up. The median follow-up time was 19.2 (4-52) months. FISH was positive in 50 (36%) patients and negative in 88 (64%) patients. A recurrence occurred in 39% of the patients with a positive FISH test and in 21% of patients with a negative FISH test. FISH positivity according to manufacturer's criteria, at the time of a negative cystoscopy, was not significantly associated with the risk of recurrence (p 5 0.12). However, the sensitivity of the FISH test to predict recurrence was significantly improved by considering specimens with rare ( 10) tetraploid cells as negative (p < 0.006). In addition, presence of 9p21 deletion was significantly associated with recurrence (p < 0.01). Notably, positive standard cytology was an independent factor for subsequent recurrence in this study (p < 0.001). Taken together, multitarget FISH may help to stratify the risk of recurrence of UC at the time of a negative follow-up cystoscopy. Defining the optimal threshold for FISH positivity requires consideration of tetraploid pattern and 9p21 deletion. Our results also emphasize the paramount importance of conventional cytology for UC surveillance. ' 2006 Wiley-Liss, Inc.Key words: bladder cancer; recurrence; fluorescence in situ hybridization; cytology; bladder washings Papillary urothelial cancers (pTa) recur in about 70% of cases and progress, in about 5%, to invasive bladder cancer. There are 2 key questions regarding the follow-up after treatment of noninvasive bladder cancer: at what intervals and for how long should the patients be subjected to follow-up cystoscopies? Since the disease can recur even after long, disease-free intervals, some authors advocate lifelong surveillance. Traditionally, indicators of an increased recurrence risk include high tumor stage and grade, multifocality and presence of carcinoma in situ (CIS). Intensity of surveillance is mostly individualized based on these clinical risk factors. 1 The classic follow-up protocol after initial tumor resection consists of cystoscopic and cytologic examinations every 3 months for 18-24 months after tumor resection, then every 6 months for the following 2 years and then annually. Cystoscopy is an efficient method for the detection of primary or recurrent bladder cancer, but it is invasive and causes discomfort to the patient. Furthermore, flat tumors or CIS may be difficult to detect. Cytology has a high specifici...

The prognostic value of cytology and fluorescence in situ hybridization in the follow‐up of nonmuscle‐invasive bladder cancer after intravesical Bacillus Calmette‐Guérin therapy

“…In fact, all G3 cytologies in this and previous studies were positive by FISH. 14,16 The challenge of cytology lies in the less certain categories. For example, 50% of post-BCG cytologies in the G2 category were FISH negative indicating a false-positive result by cytology.…”

“…FISH was performed according to the manufacturer's recommendations with minor modifications. 14 Enumeration of FISH signals was performed as previously described. 16 A FISH result was considered as positive if at least one of the following criteria was met: (i) at least 4 cells with gain of more than 1 chromosome and/or (ii) at least 12 cells with heterozygous or homozygous deletion of 9p21.…”

Evaluation of chromosomal aberrations in patients with benign conditions and reactive changes in urinary cytology

“…[6][7][8] We found previously that a tetraploid chromosomal pattern occurs in a fraction of benign cells in voided urine specimens and bladder washings from patients with benign prostatic hyperplasia. [9][10][11] Therefore, the presence of benign tetraploid cells needs to be taken into account when defining the cutoff value for a positive FISH result to avoid false-positive diagnoses. Applying stringent cutoff criteria by excluding rare cells with a tetraploid pattern, the FISH assay provides high sensitivity (80%) and specificity (95%) for the detection of malignant urothelial cells.…”

Urovysion: Considerations on modifying current evaluation scheme, including immunophenotypic targeting and locally set, statistically derived diagnostic criteria

“…The manufacturer gives guidelines, advising ORIGINAL ARTICLE abnormal DAPI morphology for targeting and preset absolute values for diagnostic cut-off, but interestingly many workgroups try to modify these criteria. Modifications include slight (11,12) or notable (24,25) changing of the recommended absolute cut-off values, partial (14,25,26) or comprehensive (13,27,28) application of percentage-based evaluation, or the use of new targeting approaches due to observations that DAPI morphology related targeting could be misleading (16). Because the number of analyzed cells varies and some of these studies fail to describe unambiguous motivation behind modified evaluation strategies, results are inconsistent and comparison is difficult (9).…”

“…Moreover, in most studies, positive/negative cell ratio is undetermined (not recommended by manufacturer either), and only binary (positive or negative) information is gained. It has been denoted that a modified scoring criteria might increase efficiency (11,12), and that percentage-based, statistical evaluation may be of importance, by providing with further classification (13). All FISH assays have a certain rate of analytic false positivity and false negativity.…”