SEER Inquiry System - Question 20031075 Details

For cases diagnosed 1998-2003: The difference between EOD-extension codes 40 and 45 is the level of the fat involved. Code 40 is subserosal fat immediately adjacent to the muscular wall of the colon inside the serosa/visceral peritoneum. Code 45 is pericolic fat in areas where there is a serosal surface or in the retroperitoneal areas of the ascending and descending colon where there is no serosa. Code 42 was added for use when it is not possible to determine whether subserosal fat or pericolic fat is involved. Code 42 should be used only when there is a reference to 'fat' (NOS) The answer for the case example above depends on the location of the primary and whether the fat referred to is within or outside the entire thickness of the colon wall. If no additional information is available, use code 42 [Fat, NOS].