title: Micropapillary urothelial carcinoma: Cytologic features in a retrospective series of urine specimens.
abstract: BACKGROUND
  The micropapillary variant of urothelial carcinoma (uPC) is a rare variant of urothelial carcinoma that carries a poor prognosis. Definitive surgery may represent optimal management of low stage tumors. Urine cytology is indispensable in the screening and follow-up of urinary tract cancer. However, cytopathological criteria for diagnosis of uPC and its differentiation from conventional urothelial carcinoma (CUC) are not well-defined.
  
  
  METHODS
  Twenty-five cases of histologically confirmed micropapillary uPC from 21 patients were compared to 25 cases of histologically confirmed high-grade CUC.
  
  
  RESULTS
  In uPC cases, cell clusters were identified in 13 of 25 specimens from 10 patients. Six of the 13 specimens containing cell clusters corresponded to surgical pathology specimens in which micropapillary carcinoma accounted for at least 50% of total carcinoma. In contrast, only 1 of the 12 urine specimens devoid of cell clusters corresponded to surgical specimens in which micropapillary carcinoma accounted for at least 50% of total carcinoma. Cytomorphologic features of urinary specimens from patients with histologically confirmed micropapillary carcinoma were generally similar to those from patients with high-grade CUC, making it difficult to distinguish these entities in exfoliative urine specimens. CONCLUSIONS AND SUMMARY: Further investigation of the core cytopathological characteristics of uPC is warranted to refine its diagnostic criteria by exfoliative urine cytology.
authors.affiliation: Department of Pathology and Cell Biology, New York-Presbyterian Hospital-Columbia University Medical Center, 630 West 168 Street, VC14-215, New York, NY 10032.
authors.forename: Jonas John
authors.initials: JJ
authors.lastname: Heymann
authors.forename: Anjali
authors.initials: A
authors.lastname: Saqi
authors.forename: Andrew Thomas
authors.initials: AT
authors.lastname: Turk
authors.forename: John
authors.initials: J
authors.lastname: Crapanzano
keywords: Cytology; carcinoma; exfoliative; micropapillary; urothelial