title: c-kit Expression in small cell carcinoma of the urinary bladder: prognostic and therapeutic implications.
abstract: The prognosis for small cell carcinoma of the urinary bladder is poor, and strategies for improved therapy are needed. Targeted therapy against the c-kit proto-oncogene has been successful in the management of gastrointestinal stromal tumor. We investigated the expression of c-kit in 52 cases of small cell carcinoma of the urinary bladder. Specimens with more than 10% of cells demonstrating strong membrane staining were considered to have positive immunostaining for c-kit. c-kit expression was detected in 21 of 52 specimens from these patients. Among the 21 specimens, seven had less than 10% staining, and were considered to be negative. Nine had 11-50% staining, and five had more than 50% staining. Overall, 14 of 52 (27%) small cell carcinomas of the urinary bladder were positive for c-kit expression. During a median follow-up of 11 months, 60% of the patients died of bladder cancer. No association was found between c-kit expression and survival or other clinicopathologic parameters. Five-year cancer-specific survivals for c-kit-positive and c-kit-negative tumors were 9 and 15%, respectively (P=0.36). A significant proportion (27%) of small cell carcinomas of the urinary bladder expressed c-kit, suggesting that it may prove useful as a therapeutic target in small cell carcinoma of the urinary bladder.
authors.affiliation: Department of Medicine, Indiana University, Indianapolis, IN 46202, USA.
authors.forename: Chong-Xian
authors.initials: CX
authors.lastname: Pan
authors.forename: Ximing J
authors.initials: XJ
authors.lastname: Yang
authors.forename: Antonio
authors.initials: A
authors.lastname: Lopez-Beltran
authors.forename: Gregory T
authors.initials: GT
authors.lastname: MacLennan
authors.forename: John N
authors.initials: JN
authors.lastname: Eble
authors.forename: Michael O
authors.initials: MO
authors.lastname: Koch
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Jones
authors.forename: Haiqun
authors.initials: H
authors.lastname: Lin
authors.forename: Kelly
authors.initials: K
authors.lastname: Nigro
authors.forename: Veronica
authors.initials: V
authors.lastname: Papavero
authors.forename: Maria
authors.initials: M
authors.lastname: Tretiakova
authors.forename: Liang
authors.initials: L
authors.lastname: Cheng
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001549:Benzamides; D018288:Carcinoma, Small Cell / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D000068877:Imatinib Mesylate; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use; D011379:Prognosis; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D000090063:Proto-Oncogene Mas; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis*; D011743:Pyrimidines / Q000627:therapeutic use; D016019:Survival Analysis; D001743:Urinary Bladder / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000378:metabolism / Q000473:pathology*
chemical_list: D001549:Benzamides; C000715470:MAS1 protein, human; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D000090063:Proto-Oncogene Mas; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D019009:Proto-Oncogene Proteins c-kit