Colon

• Multiple tumors/polyps
  Which ones should be counted independently and which ones are part of the same disease process? When a polyp is biopsied and the resection shows residual, plain adenocarcinoma in the same area, what histology histology code is the best to use?
• Contiguous/overlapping sites
  Tumors at the rectosigmoid junction and ileocecal valve have long been a problem
• Time between diagnoses
  For a patient with multiple colon polyps, is timing a factor in making the diagnosis?
• NOS versus specific histology
  Pathologists have specific criteria for diagnosing certain colon malignancies that are not understood by most registrars. Clearer definitions and criteria for coding are needed for:
  • Mucinous adenocarcinoma
  • Neuroendocrine carcinoma
  • Signet ring cell adenocarcinoma
  • Undifferentiated carcinoma
• Adenocarcinoma, NOS
  A very common diagnosis for colon; are there indications in the pathology report that a more specific diagnosis is warranted?
• Adenocarcinoma with mixed subtypes
  Are there specific histologies that comprise this diagnosis for colon cancer?