Background: The incidence of primary small cell carcinoma (SCC) of the urinary bladder is extremely rare. We sought to analyze the cytologic and immunophenotypic features of SCC of the urinary bladder in urine and reassert the importance of cytologic examination of urine specimens for diagnosis of this tumor. Methods: We studied the clinical and cytomorphologic features in the presurgical urine specimens (4 voided urine and 2 bladder-washing specimens) of histopathologically and immunohistochemically proven cases of SCC of the urinary bladder. Results: There were 6 cases, all males, with an age range of 61-81 years. On cytologic and histopathologic examination, typical SCC morphology was present in all cases. On immunohistochemistry, synaptophysin and CD56 were positive in all 6 cases, while chromogranin was positive in only 3. The Ki-67 labeling index ranged from 30 to 100%. Conclusions: SCC should be kept in the differential diagnosis, when high-grade urothelial carcinoma is suspected in a urine cytology specimen, as this distinction has important therapeutic and prognostic implications. Therefore, a careful observation and, if required, the use of an appropriate immunocytochemical panel on the presurgical urine specimens can lead to a correct diagnosis.

Ismaili N: A rare bladder cancer - small cell carcinoma: review and update. Orphanet J Rare Dis 2011;6:75.
Yoshida K, Ishida M, Kagotani A, Iwamoto N, Iwai M, Okabe H: Small cell carcinoma of the urinary bladder and prostate: cytological analyses of four cases with emphasis on the usefulness of cytological examination. Oncol Lett 2014;7:369-372.
Acs G, Gupta PK, Baloch ZW: Cytomorphology of high-grade neuroendocrine carcinoma of the urinary tract. Diagn Cytopathol 2000;23:92-96.
Zhao X, Flynn EA: Small cell carcinoma of the urinary bladder: a rare, aggressive neuroendocrine malignancy. Arch Pathol Lab Med 2012;136:1451-1459.
Şimşek GG, Güreşçi S, Oğuz U, Ünsal A: Cytological diagnosis of small cell carcinoma of urinary bladder in a patient with CLL. Cell J (Yakhteh): 2014;16:95-98.
Wang X, MacLennan GT, Lopez-Beltran A, Cheng L: Small cell carcinoma of the urinary bladder - histogenesis, genetics, diagnosis, biomarkers, treatment, and prognosis. Appl Immunohistochem Mol Morphol 2007;15:8-18.
Ko H, Park SY, Cha EJ, Sohn JS: Primary small cell carcinoma of the urinary bladder: a case report demonstrates cytological findings in SurePath liquid-based cytology. Cytopathology 2014;25:135-136.
Ali SZ, Reuter VE, Zakowski MF: Small cell neuroendocrine carcinoma of the urinary bladder. A clinicopathologic study with emphasis on cytologic features. Cancer 1997;79:356-361.
Dowsett M, Nielsen TO, A'Hern R, Bartlett J, Coombes RC, Cuzick J, Ellis M, Henry NL, Hugh JC, Lively T, McShane L, Paik S, Penault-Llorca F, Prudkin L, Regan M, Salter J, Sotiriou C, Smith IE, Viale G, Zujewski JA, Hayes DF: Assessment of Ki-67 in breast cancer: recommendations from the International Ki67 in Breast Cancer Working Group. J Natl Cancer Inst 2011;103:1656-1564.
Dhall D, Mertens R, Bresee C, Parakh R, Wang HL, Li M, Dhall G, Colquhoun SD, Ines D, Chung F, Yu R, Nissen NN, Wolin E: Ki-67 proliferative index predicts progression-free survival of patients with well-differentiated ileal neuroendocrine tumors. Hum Pathol 2012;43:489-495.
Rindi G, Arnold R, Bosman FT, et al: Nomenclature and classification of neuroendocrine neoplasms of the digestive system; in Bosman FT, Carneiro F, Hruban RH, Theise ND (eds): WHO Classification of Tumours of the Digestive System. Lyon, IARC Press, 2010, p 13.
Travis WD, Brambilla E, Muller-Hermelink HK, Harris CC (eds): WHO Classification of Tumours: Pathology and Genetics of Tumours of the Lung, Pleura, Thymus and Heart. Lyon, IARC Press, 2004.
Edge SB, Byrd DR, Compton CC, Fritz AG, Greene FL, Trotti A (eds): AJCC Cancer Staging Manual, ed 7. Springer, 2009, p 184.
Shatagopam K, Kaimakliotis HZ, Cheng L, Koch MO: Genitourinary small cell malignancies: prostate and bladder. Future Oncol 2015;11:479-488.
Wang X, Zhang S, MacLennan GT, Eble JN, Lopez-Beltran A, Yang XJ, Pan CX, Zhou H, Montironi R, Cheng L: Epidermal growth factor receptor protein expression and gene amplification in small cell carcinoma of urinary bladder. Clin Cancer Res 2007;13:953-957.
Bobos M, Hytiroglou P, Kostopoulos I, Karkavelas G, Papadimitriou CS: Immunohistochemical distinction between Merkel cell carcinoma and small cell carcinoma of the lung. Am J Dermatopathol 2006;28:99-104.
McFall MJ, Mohanty SK, Liles G, Lugo H, Chung F, Knudsen B, Yuan X, Amin MB, Dhall D, Balzer B: Diagnostic utility of an expanded panel of novel and well-established immunohistochemical (IHC) markers to differentiate Merkel cell carcinoma from high-grade non-Merkel cell neuroendocrine carcinomas. Mod Pathol 2014;27:137A.
Mohanty SK, Smith SC, Chang E, Luthringer DJ, Gown AM, Aron M, Amin MB: Evaluation of contemporary prostate and urothelial lineage biomarkers in a consecutive cohort of poorly differentiated bladder neck carcinomas. Am J Clin Pathol 2014;142:173-183.
Kaufmann O, Dietel M: Expression of thyroid transcription factor-1 in pulmonary and extrapulmonary small cell carcinomas and other neuroendocrine carcinomas of various primary sites. Histopathology 2000;36:415-420.
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