Fine needle aspiration cytology of a case of micropapillary variant of urothelial carcinoma of bladder

Abstract

Neoplastic urothelium has the capacity to demonstrate enormous plasticity. A variety of unusual morphological variants of urothelial carcinoma have been described. Micropapillary variant of urothelial carcinoma is a rare and recently described bladder tumor, associated with poor prognosis. We present the cytological features of micropapillary urothelial carcinoma in a 65-year-old man with bladder mass. The cytological features include tightly cohesive clusters of micropapillary component admixed with urothelial carcinoma. Histopathological sections showed small nests of tumor cells residing within the lacunae. Establishing a diagnosis of micropapillary urothelial carcinoma indicates a high-grade and high-stage tumor with poor outcome, requiring an aggressive therapy. It is thus important for the cytopathologist to recognise micropapillary variant of urothelial carcinoma, for early and better management of patients with bladder tumor.

Cytological Findings of the Micropapillary Variant of Urothelial Carcinoma: A Comparison with Typical High-Grade Urothelial Carcinoma

“…However, if the background is extensively necrotic, the possibility of MPUC can be low in urine cytology specimens. In previous reports, most MPUC cases showed a high N/C ratio 5-10. However, in our study, we found that the N/C ratio of MPUC was moderate to high-the same as that of HGUC.…”

“…According to the previous reports, the most characteristic cytologic finding of this study was prominent small and tight cellular clusters 5-10. The morphology of the clusters was variable, showing spheroid patterns, three-dimensional cell balls, rosette-like clusters and micropapillary patterns without fibrovascular cores.…”

Micropapillary Carcinoma of the Urinary Tract: A Cytologic Study of Urine and Fine-Needle Aspirate Samples

“…The cytology of this MPC variant is basically a mixture of a high-grade urothelial carcinoma with partial architectural features of a low-grade neoplasm [9]. Previous cytologic reports include two series and a few case reports, some of which involve FNA [9,10,11,12,13,14,15,16]. The present study is generally in agreement with these previous papers, which report a predominance of smears, showing atypical cells distributed mainly as tight clusters.…”

“…Cytologic reports describing features of the micropapillary variant of transitional cell carcinoma are still scarce [9,10,11,12,13,14,15,16]. The two published series show some differences probably related to different methods employed in the selection, collection and processing of the specimens [14,16].…”