ASP.NET trigger event on main thread?

Question

ASP.NET

Briefly:
There is an application, in the main thread all the necessary resources, i.e. sessions and services.
In a separate thread I listen to a specific URL and when it says do the job.
You need to do the work on the main thread.
tried events and backgroundworker all they do is execute everything in a child thread...

static Action<object> listeningOrchard = (object sender) =>
        {

           
            while (true)
            {

                ///ждем обновлений
                var needUpdate = false;

                try
                {

                    using (var client = new WebClient())
                    {
                        client.CachePolicy = new RequestCachePolicy(RequestCacheLevel.NoCacheNoStore);

                        
                          
                        var text = client.DownloadString("http://localhost:8000/UpdateListener");



                        bool.TryParse(text, out needUpdate);

                     

                        client.Dispose();




                    }

                }
                catch (Exception ex)
                {

                 


                }

                if (!needUpdate)
                {
                
                }
                else
                {
                   //тут должен быть вызов метода из основного потока
                }


            }
        };