Cytopathology Challenge Cases 2009 January 20 March 13 March 30 April 17 2008 February 1 March 1 (Koss Classics for RISE) July 21 August 1 August 18 September 1 September 15 September 29 October 17 October 31 December 12 2007 September 10 September 17 September 24 October 1 October 15 October 22 October 29 November 5