Cone Beam CT Scanning in Lung and Bladder Cancer.

Inclusion Criteria: * Patient has biopsy proven limited stage SCLC * receiving radical concurrent chemoradiotherapy * no prior chest RT * no prior surgical resection of lung tumor * no prior chemotherapy * patients' lung tumors should be centrally-located to minimize the effect of respiratory motion * patient has biopsy proven TCC bladder * receiving radical concurrent chemoradiotherapy or RT alone * no prior chemotherapy * patient signs study-specific consent form Exclusion Criteria: * mixed small cell and non small cell histology * patient not being treated with concurrent chemoradiotherapy * chemoradiotherapy given sequentially * previous chest RT * previous chemotherapy * prior surgical resection of lung mass * patient ineligible for pelvic RT * patient does not sign study consent