Insights from a whole cystectomy specimen—association of primary small cell carcinoma of the bladder with transitional cell carcinoma in situ

Gaisa, Nadine Therese; Tilki, Derya; Losen, Inge; Dahl, Edgar; Stoehr, Robert; Stief, Christian Georg; Knüchel, Ruth

doi:10.1016/j.humpath.2007.12.017

« Previous Next »Human Pathology
Volume 39, Issue 8 , Pages 1258-1262, August 2008

Insights from a whole cystectomy specimen—association of primary small cell carcinoma of the bladder with transitional cell carcinoma in situ

Nadine Therese Gaisa, MD
- Institute of Pathology, RWTH Aachen University, 52074 Aachen, Germany
Derya Tilki, MD
- Department of Urology, University Hospital Munich-Großhadern, LMU Munich, 81377 München, Germany
Inge Losen
- Institute of Pathology, RWTH Aachen University, 52074 Aachen, Germany
Edgar Dahl, PhD
- Institute of Pathology, RWTH Aachen University, 52074 Aachen, Germany
Robert Stoehr, PhD
- Institute of Pathology, University Hospital Erlangen, 91054 Erlangen, Germany
Christian Georg Stief, MD
- Department of Urology, University Hospital Munich-Großhadern, LMU Munich, 81377 München, Germany
Ruth Knüchel, MD
- Institute of Pathology, RWTH Aachen University, 52074 Aachen, Germany
- Corresponding author. Institute of Pathology, RWTH Aachen University, 52074 Aachen, Germany.

Received 7 December 2007; accepted 27 December 2007. published online 11 June 2008.

Summary

Small cell carcinoma of the urinary bladder is a rare entity known as an aggressive tumor. As it is rarely associated with transitional cell carcinoma in situ but more commonly with invasive transitional cell carcinoma, its origin is not well understood. We report a case of small cell carcinoma with coexisting transitional cell carcinoma in situ, where histologic mapping and parallel immunohistochemical and molecular analyses (TP53 mutation analyses, loss of heterozygosity) were performed. Immunohistochemical characterization (synaptophysin, thyroid transcription factor-1, chromogranin A, neuron specific enolase, CD56, CK, CK7, CK20, CD44v6, and p53) emphasized the morphology. Identical point mutations of TP53 were identified in invasive small cell carcinoma and transitional cell carcinoma in situ. No loss of heterozygosity of microsatellite markers D3S3050, D9S303, D9S304, D9S171, D9S775, D9S1748, D9S1751, D17S786, D17S918, and TP53alu was found in either component. We provide, for the first time, molecular evidence for the development of invasive small cell carcinoma out of transitional cell carcinoma in situ.

Keywords: Small cell carcinoma of the urinary bladder, Transitional cell carcinoma in situ, TP53