Recent advances in our understanding of genetic and epigenetic events in colorectal cancer have resulted in the need to modify many of our previously held ideas about diagnosing seemingly "simple" polyps and "straightforward" colon cancers. With the elucidation of critical pathways, reporting has become more complex. Additional assessment of prognostic and predictive factors is increasingly relevant to patient care with the push for personalized medicine. In order to keep up with increasing demands for more sophisticated information, a basic understanding of the molecular underpinnings of colorectal neoplasia is essential.

This course will focus on colorectal polyps and carcinomas. Emphasis will be placed on the morphologic findings, diagnostic criteria, evolving terminology, and differential diagnosis in colorectal polyps, polyposis syndromes, and carcinoma. The role of ancillary studies including immunohistochemical and molecular testing will be discussed, including their relevance to the contemporary surgical pathology report. A case study format will be utilized.

Topics to be discussed include the following: 1) Microsatellite unstable colorectal carcinomas including those due to Lynch syndrome and occurring sporadically; 2) Serrated polyps, including those occurring in the hyperplastic polyposis syndrome, and their differential diagnosis; 3) Hamartomatous polyposis syndromes and sporadic morphologic counterparts; 4) Problem areas in staging and reporting colon cancers, with special emphasis on the changes in the 7th edition of the AJCC Cancer Staging Manual; 5) Immunophenotype of colon cancer; 6) Significance of assessment of EGFR signaling pathway activation in metastatic colon cancer.

Upon completion of the course, participants will be able to: 1) understand the microsatellite unstable (MSI-H) pathway to colorectal neoplasia and know the morphologic and immunohistochemical features and nomenclature of MSI-H carcinomas and their precursors; 2) recognize the various hamartomatous polyps and their clinical significance regarding familial cancer syndromes; 3) understand common errors in colon cancer reporting and key changes in the 7th edition of the AJCC Staging Manual; 4) know the diagnostic, prognostic, and therapeutic implications of MSI testing/MMR protein immunohistochemistry and BRAF and KRAS mutation analysis.

The course is designed for residents, fellows, and general pathologists, as well as those with an interest in GI pathology. Virtual slides and still images, along with histories, will be posted on the USCAP website for review by pre-registrants prior to the meeting. All participants will also receive a syllabus with a comprehensive reference list at the meeting. After the meeting, participants will receive web access to the PowerPoint presentation given at the Annual Meeting along with the text portion of the syllabus.

This course may be used for CME credits or SAM credits.