Similar instruments have revolutionized the diagnosis of tumors in the stomach and bowel. With a flexible gastroscope or colonoscope, the entire stomach or colon can be clearly seen and pieces of tissue can be collected. Similar specialized instruments for other body cavities have made diagnostic procedures much safer. And the procedures can be repeated after treatment to see how effective the treatment has been.
Clever adaptations of these endoscopic methods and tools are sometimes used for specialized diagnosis and therapy. In a procedure called endoscopic retrograde cholangiopancreatography (ERCP), for example, a doctor can pass a flexible fiber-optic telescope into your stomach, visualize the opening of the ducts releasing bile from the liver, insert a tube (stent) into these ducts from inside the stomach either to provide drainage or to take pictures showing the exact location of tumors in the bile ducts and exactly how involved the ducts are.
A new technique is used when lung cancers partially or completely block air passages or when a tumor blocks the esophagus or colon. A beam of laser light can be passed through a flexible scope to create or enlarge an opening in the center of the tumor ( see "Laser Therapy" ).
