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During the past few years there has been renewed interest in the management of chronic anal fissure. Treatment with botulinum neurotoxin is less expensive and easier to perform than surgery and does not require anesthesia. It is also more efficacious than nitrate therapy and is not related to the patient's willingness to complete treatment.
Gallstone disease continues to be a significant problem. The recent identification of mouse genes may help determine susceptibility to the disease. An infectious etiology hypothesis has also been proposed to explain the development of gallstones. Could these discoveries lead to more effective strategies for the prevention and treatment of gallstones?
At present, there is no standard treatment for cholangiocarcinoma, a fatal cancer of the biliary tree. New therapies for cholangiocarcinoma are difficult to evaluate because treatment endpoints are ill-defined. This viewpoint explains why the current endpoints are problematic and proposes a new quantitative system for assessing disease progression.