public Geometry GetShape()

// methods need to run on the MCT
ArcGIS.Desktop.Framework.Threading.Tasks.QueuedTask.Run(() =>
{
  try
  {
    // open a gdb
    using (ArcGIS.Core.Data.Geodatabase gdb = 
              new ArcGIS.Core.Data.Geodatabase(
                  new FileGeodatabaseConnectionPath(new Uri(@"c:\Temp\MyDatabase.gdb"))))
    {
      //Open a featureClass 
      using (ArcGIS.Core.Data.FeatureClass featureClass = 
                     gdb.OpenDataset<ArcGIS.Core.Data.FeatureClass>("Polygon"))
      {
        
        ArcGIS.Core.Data.QueryFilter filter = 
                   new ArcGIS.Core.Data.QueryFilter()
                    {
                      WhereClause = "OBJECTID = 6"
                    };

        // get the row
        using (ArcGIS.Core.Data.RowCursor rowCursor = 
                               featureClass.Search(filter, false))
        {
          while (rowCursor.MoveNext())
          {
            using (var row = rowCursor.Current)
            {
              long oid = row.GetObjectID();

              // get the shape from the row
              ArcGIS.Core.Data.Feature feature = row as ArcGIS.Core.Data.Feature;
              Polygon polygon = feature.GetShape() as Polygon;

              // do something here
            }
          }
        }
      }
    }
  }
  catch (Exception ex)
  {
    // error - handle appropriately
  }
});

//Change map frame extent to single feature with 10 percent buffer

//Process on the worker thread
await QueuedTask.Run(() =>
{
  //Reference the mapframe and its associated map
  MapFrame mf = layout.FindElement("Map Frame") as MapFrame;
  Map m = mf.Map;

  //Reference a feature layer and build a query (to return a single feature)
  FeatureLayer fl = m.FindLayers("GreatLakes").First() as FeatureLayer;
  QueryFilter qf = new QueryFilter();
  string whereClause = "NAME = 'Lake Erie'";
  qf.WhereClause = whereClause;

  //Zoom to the feature
  using (ArcGIS.Core.Data.RowCursor rowCursor = fl.Search(qf))
  {
    while (rowCursor.MoveNext())
    {
      //Get the shape from the row and set extent
      using (var feature = rowCursor.Current as ArcGIS.Core.Data.Feature)
      {
        Polygon polygon = feature.GetShape() as Polygon;
        Envelope env = polygon.Extent as Envelope;
        mf.SetCamera(env);

        //Zoom out 15 percent
        Camera cam = mf.Camera;
        cam.Scale = cam.Scale * 1.15;
        mf.SetCamera(cam);
      }
    }
  }
});