Cytomorphological characteristics of low-grade papillary urothelial carcinoma for differential diagnosis from benign papillary urothelial lesions: logistic regression analysis in SurePath(™) liquid-based voided urine cytology

Cytomorphological characteristics of low-grade papillary urothelial carcinoma in voided urine samples: Distinction from benign and high-grade papillary urothelial carcinoma

OBJECTIVE

Given its frequent recurrence and the potential for high-grade transformation, accurate diagnosis of low-grade papillary urothelial carcinoma (LGPUC) in urine cytology is clinically important. We attempted to identify cytomorphologic features in urine samples, which could be helpful for the identification of LGPUC.

METHODS

We conducted a retrospective review of voided urine specimens collected from patients with histopathologic diagnoses of LGPUC. Their cytomorphological features were compared with those from patients with benign conditions and high-grade papillary urothelial carcinoma (HGPUC).

RESULTS

A total of 115 voided urine specimens were evaluated, including 30 benign, 41 LGPUC, and 44 HGPUC cases. In LGPUC, 18 cases (44%) were diagnosed as atypical, a proportion significantly higher than that observed in benign cases (4 cases, 13%), while the remaining 23 cases (56%) were diagnosed as negative. LGPUC urine samples tended to have higher cellularity than benign cases, but the difference was not statistically significant. Three cytological features, namely nuclear enlargement, higher nuclear-to-cytoplasmic (N/C) ratio, and presence of small cell clusters, were statistically more prevalent in LGPUC compared to benign cases, although the changes were relatively subtle. In contrast, cytomorphological distinction between LGPUC and HGPUC was evident, as high cellularity, nuclear enlargement, hyperchromasia, high N/C ratio, irregular nuclear membrane, and apoptosis were significantly more prevalent in HGPUC cases.

CONCLUSIONS

Several cytomorphologic features in voided urine samples were more prevalent in cases with LGPUC, albeit not observed in all instances. Since these alterations were relatively subtle, meticulous attention to these cytomorphologic details is crucial to suggest the possibility of LGPUC.

Clinical application of the anti-human telomerase reverse transcriptase (hTERT) antibody (SCD-A7) immunocytochemistry in liquid-based urine cytology: A prospective, single institute study

OBJECTIVES

Urine cytology is the most widely used noninvasive screening tool for urothelial carcinoma diagnosis and surveillance. Although highly specific, urine cytology exhibits suboptimal sensitivity. This study aimed to determine whether hTERT immunocytochemistry (ICC) could be applicable as an ancillary test in routine cytology practice.

METHODS

A total of 561 urinary tract samples were initially screened in this study. All of them were prepared using SurePath liquid-based cytology (LBC), while additional LBC slides were made and subsequently used for hTERT (SCD-A7) ICC.

RESULTS

From the 561 samples screened, 337 were finally analyzed, all having an adequate cellularity and available follow-up histology. The hTERT ICC-positive rate was 95.9% (n = 208/217), 96% (n = 24/25), and 100% (n = 4/4) in cytology samples with high-grade urothelial carcinoma, carcinoma in situ, and low-grade urothelial carcinoma subsequent histology. Among the 64 atypical cytology cases histologically confirmed as urothelial carcinomas, 92.2% (n = 59/64) were immunoreactive to hTERT, whereas the two histologically benign cases were ICC-negative. 87/90 (96.7%) of the cytology cases confirmed to be benign in follow-up were hTERT-negative. The overall sensitivity and specificity of hTERT ICC were 96.3% and 98.8%, respectively (AUROC = 0.963; 95% CI = 0.960-0.967).

CONCLUSIONS

The hTERT ICC test exhibited consistent and intense staining in malignant urothelial cells, suggesting its value as an ancillary test in liquid-based urine cytology.

Is Diagnosis of Low-Grade Urothelial Carcinoma Possible in Urine Cytology?

Background:

Urine cytology is a useful modality, primarily for the diagnosis and follow-up surveillance of high-grade urothelial carcinoma (HGUC). Its utility in diagnosing low-grade urothelial carcinoma (LGUC) remains controversial because of low reported sensitivity compared to cystoscopy.

Aim:

To study the cytomorphology of LGUC in voided urine samples and analyze its utility in diagnosis.

Materials and Methods:

This is a retrospective study of one year, including 48 voided urine samples in cases which were confirmed as LGUC on subsequent histology. Urine cytology smears of these cases, originally stained with Papanicolaou stain were reviewed, critically analyzed and the specific cytomorphologic and cystoscopic findings were documented.

Results:

On review 18 samples were re-categorized as LGUC which included 10 samples initially diagnosed as Negative for HGUC, 2 as Atypical Urothelial Cells – Not Otherwise Specified (AUC-NOS) and 6 as Suspicious for Carcinoma. In addition, another 3 samples with initial diagnosis of LGUC remained as LGUC on review. Thus, a total of 21 LGUC samples were identified after the review. 26 (54%) samples with a diagnosis of negative for HGUC remained negative even after review, as the tumor cells were not identified either due to sampling error or unrecognizable morphology. One (2%) samples of AUC-NOS remained the same on review due to very scant atypical cells. In 21 LGUC samples, cytology showed a dual population of benign differentiated urothelial cells and small urothelial cells with subtle nuclear atypia such as irregular and thickened nuclear membrane with increased nuclear cytoplasmic ratio. In 12 false negative LGUC samples, the diagnostic cells were camouflaged by their subtle nuclear atypia coupled with an overwhelming background of differentiated benign urothelial cells as both appeared almost similar in morphology. Papillary fragments were identified only in 2 samples.

Conclusions:

Diagnosis of LGUC on cytology is challenging and depends on the presence of diagnostic cells, pick up of diagnostic cells on screening and accurate interpretation. Special attention to papillary fragments and aforementioned nuclear atypia should be paid as tumor cells may resemble normal urothelial cells and can be easily missed.

Immunocytochemical expression of Ki-67/p16 in normal, atypical, and neoplastic cells in urine cytology using BD SurePath™ as preparation method

OBJECTIVE

The objective of this study was to investigate the expression of Ki-67/p16 in urothelial cells in cytological material.

MATERIALS AND METHODS

There were 142 urines including normal controls, anonymous rest urine, controls after treatment for urothelial carcinoma (UC) and newly diagnosed UC. Immunocytochemistry for ki-67/p16 dual staining kit was performed on all specimens.

RESULTS

Eight high-grade UC and six anonymous specimens showed dual positivity. None of the low-grade UC or the control specimens after treated UC showed dual staining. Fifteen of 84 (17.8%) symptomatic cases were negative for both markers, and 59/84 (70.2%) showed positivity for both but not dual staining. Twenty-seven of 84 cases were positive for either Ki-67 (n = 22) or p16 (n = 5). Normal controls and benign specimens were negative for p16.

CONCLUSIONS

Co-expression of p16/Ki-67 in the same cells was found in 16.6% of the cases. All were high grade, and co-expression seems to have limited practical impact as an additional marker in urine cytology. Any positivity for p16 alone strongly indicates malignancy. Negative p16 accompanied by a positive Ki-67 rate at 5% or more could be considered as an additional marker for further clinical follow-up. Both markers, co-expressed and separate, can give additional information in follow-up patients after treatment for UC.

The cytomorphological features of low-grade urothelial neoplasms vary by specimen type

BACKGROUND

Urinary tract (UT) cytology has been used successfully to diagnose high-grade urothelial carcinoma but is reported to have poor sensitivity for low-grade urothelial neoplasms (LGUNs). However, the literature has shown that LGUN may be associated with atypical findings in UT specimens. The authors determined which features were most commonly observed, and whether the method of specimen procurement had an effect.

METHODS

A total of 326 specimens were identified over an 8-year period. One hundred fifty-three specimens were reviewed and graded for cellularity, number of tissue fragments (TFs), degeneration, inflammation, hyperchromasia, nuclear pleomorphism, nuclear border irregularity, nuclear size, cytoplasmic tails, nuclear eccentricity, and high-grade features.

RESULTS

Of the 153 specimens, 86 specimens (56.2%) demonstrated cellular atypia; of those, 51.2% were voided urine (VU) and 31.4% were UT washing (UW) specimens. The majority of specimens had many cells (46.5%), many single cells (44.2%), few to moderate TFs (46.5% and 27.9%, respectively), mild hyperchromasia (52.3%), mild nuclear pleomorphism (51.2%), mild nuclear border irregularity (60.5%), cytoplasmic tails (51.2%), and few to moderate eccentric nuclei (37.2% and 36.1%, respectively). The presence of TFs, cytoplasmic tails, and eccentric and enlarged nuclei were significantly more common in UW versus VU specimens (P = .036, .012, .014, and .027, respectively) and in UW versus benign UW controls (P = .001, .002, .002, and .003, respectively).

CONCLUSIONS

Approximately 50% of UT specimens with LGUN on follow-up demonstrated atypical features. Based on comparison with benign UW controls, TFs, cytoplasmic tails, nuclear eccentricity, and enlarged nuclei were more pronounced in neoplastic UW than VU specimens, suggesting that the method of urine specimen procurement affects the presence of certain low-grade features. Cancer Cytopathol 2016;124:552-64. © 2016 American Cancer Society.