Asp.net WebAPI HTTP SERVER ERRORS - user breaks the connection

I have a Web.Api project, and I deployed it to Azure Web Sites. Some times I see many HTTP SERVER ERRORS in dashboard.

Detailed Error Information: Module ManagedPipelineHandler Notification ExecuteRequestHandler Handler System.Web.Http.WebHost.HttpControllerHandler Error Code 0x800703e3 Requested URL http://test-server:80/api/Statistics/ShowStories Physical Path D:\home\site\wwwroot\api\Statistics\ShowStories Logon Method Anonymous Logon User Anonymous

I don't know how to fix it and why it happens.

UPDATE

I found what this happens because user breaks the internet connections, and my question in next: how to catch this problems, maybe create some custom exception handler, and logger this problems, what this 'http server errors' and not show to Azure dashboard?

See this question: ASP.NET Web API OperationCanceledException when browser cancels the request

I think that if you handle OperationCanceledException correctly, the error will not be logged.