Histology (Pre-2007)--Pancreas: Should pancreatic neoplasia III (PanIN III) be coded to 8010/2 [carcinoma in situ, NOS] or 8500/2 [Ductal carcinoma in situ]? See Description.
Histology (Pre-2007)/Primary Site/Diagnostic Confirmation: How would these fields be coded for a diagnosis of cholangiocarcinoma based on clinical findings only? See Discussion.
Histology (Pre-2007): What code is used to represent the histology adenocarcinoma with "areas of" papillary architecture and "foci of" squamous differentiation? Even though "areas of" and "foci" are non-majority terms, should histology be coded to the combination code of adenocarcinoma with mixed subtypes [8255/3]?
Histology--Brain and CNS: Provide clarification about the priority order of histology coding sources and an explanation of why the annotated histology lists are not the same as the WHO IARC ICD-O-3.2 Excel Table (adopted 1/1/2021). See Discussion.