Absence of karyotype abnormalities in patients with familial urothelial cell carcinoma

Objectives. In a previous pilot study, a constitutional balanced translocation t(5;20)(p15;q11) was identified in a family with urothelial cell carcinoma (UCC). The purpose of this study was to find (additional) constitutional chromosomal abnormalities in selected families to obtain an indication for genome location(s) of UCC susceptibility gene(s). Methods. UCC families were selected through an ongoing study on familial clustering of UCC, the largest study on this subject ever performed. This study included 1193 new patients with UCC of the bladder, ureter, and renal pelvis, identified from the population-based cancer registries of the Dutch Comprehensive Cancer Centers East and South. Information on demographic factors, smoking habits, and family history of UCC was collected by postal questionnaires. UCC in the families was verified with pathology reports. Thirty families were selected in which 2 or 3 individuals were affected, preferably diagnosed at a relatively young age. Blood samples were obtained from all probands, and routine cytogenetic analysis was performed on 23 male and 7 female UCC patients. Subsequent spectral karyotyping was performed in 4 patients from families, which were most suggestive for an inherited etiology. Results. No aberrant chromosomal features were found by either classical or spectral karyotype analyses. Conclusions. It is conceivable that genetic germline abnormalities do exist in the patients in our study but are below the detection limit of the explorative methods used in this study.