BLADDER WASHING CYTOLOGY: USABILITY DURING FOLLOW-UP AFTER INTRAVESICAL MITOMYCIN C FOR NONINVASIVE UROTHELIAL CANCER

Abstract

Abstract

Introduction: Cytoscopic evaluation alone is inadequate in detecting residual tumor after intravesical

therapy. Intravesical experimental evidence indicates that mitomycin C cause denudation and flattening of the

noninvasive ürothelial tumors, often leaving tumor which may not be visible on endoscopic examination.

Cytology has limited value for low grade tumors because of the toxic and metabolic effects of the intravesical

chemotherapatic agents on the urothelial epithelium. Aim of this study is to review our experience regarding

the value of urine cytology on follow up after intravesical mitomycin C therapy for noninvasive urothelial

cancer in addition to observe any potential therapy induced-influence of mitomycin C.

Materials and Methods: Study group consisted of 31 patients, after exclusion of 3 patients, 28 patients were

given courses of intravesical mitomycin C for recurrent or newly diagnosed noninvasive urothelial carcinoma

of the bladder. All of the 28 patients were underwent cytoscopy, bladder washings and TUR before and 4

weeks after therapy. Cytospin slides were stained with May Grünwald Giemsa. Four cyto-diagnostic

categories were applied: nondiagnostic, benign, suspicous and malignant. Besides, cellular parameters such as

background, cellularity, nuclear& cytoplasmic features were evaluated. In histopathologic evaluation, cases

were graded according to 2004 WHO classification.

Results: Of the 28 patients treated, 13 had complete responses while 10 had partial responses and 5 were

nonresponders. Distribution of diagnosis in study population was as follows: 13 cases benign; 9 cases

malignant; 6 cases suspicious. Although in majority of cases, cytological features depending on –obviouslymetabolic

and toxic effects of MMC were observed; six cases were diagnosed as suspicious since nuclear

hyperchromasia and nucleomegaly were conspicious. In complete response group; sensitivity, specificity and

accuracy rates for urothelial carcinomas were 66.6%, 55.5%, 58,3%, respectively; in low grade tumors and

100%, 100%, 100% for high grade tumors respectively. Among the tumors with partial response, low grade

tumors displayed 100%, 83.3%, 85.7% and high grade ones had 100%, 100%, 100% sensitivity, specificity and

accuracy rates, respectively.

Conclusion: Our data suggest that cytologic evaluation was an accurate predictor of residual tumor or

new tumor occurrence for patients with initial high grade ürothelial tumors. However, it reflects a reduced

sensitivity of urinary cytology in low grade category due to the overlapping of cytopathic and/or real

malignant cellular changes. In other words for low grade category, positive urine cytologic data, in the absence

of endoscopically detectable tumor, can be assumed to represent either residual cancer or cytopathic effects of

the Mitomycin-C therapy. Team cooperation between the urologist and (cyto) pathologist is crucial for follow

up after treatment of urothelial carcinomas.