Tumor tissue is obtained at baseline (at the original or confirmatory transurethral resection of the bladder tumor) and at the time of cystectomy for analysis of drug-specific and tissue-based biomarkers by western blot, immunohistochemistry, and gene array techniques. Histopathological, molecular, and genetic correlates are analyzed to better understand the potential effects of the epidermal growth factor receptor (EGFR) inhibition in transitional cell carcinoma and to determine the effect of neoadjuvant erlotinib on gene expression. Tumor tissue is also evaluated by real-time polymerase chain reaction to confirm drug effects on expected targets and on EGFR expression, activity, and affected signaling pathways in the disease state and by microarray analysis to define expression phenotypes correlating with outcome, distinguish responders from nonresponders, and determine effects of drug treatment on gene expression in disease.