It basically means that the pathologist noted the presence of areas in which there were groups of 'immune-type' cells. I assume this was noted because either the area where they were found or the number of the aggregates found were higher than normal.
The colon (as well as much of the GI tract) has an immune system within it. In some cases the immune cells are individually scattered throughout the tissue. In other cases the immune cells group, or aggregate. All these are under 'normal' conditions.
In a pathology report however, you don't typically see the 'normal' unless it's stated that 'normal numbers of submucosal lymphoid aggregates were found. So I'm assuming the statement was a 'note' to your GI doctor to gently nudge him by saying that. Some pathologists whould say something like 'clinical correlation should be made,' or some such thing, but many pathologists will not step on a GI doc's toes.
The problem with this statement is that it doesn't tell you about the number, diameter, lymphocyte distribution, or the proliferative index. All it says is 'you've got them' and apparently the pathologist thought it might be significant. But without further clarification your doc can easily say 'everything is normal.'
Lymphoid aggregates are generally regarded as 'protective,' and can be found in a number of conditions in which an inflammatory reaction may be starting or is on-going.
Who are you? are you a pathologist or a medical doctor? If you're not, where do you get your info from?
Nikki333 has not posted anywhere on MedHelp in over 2 years. If you want to try and reach her, you should send her a note or a private message. If you have a medical question, you can post your question as a separate post.
Almost certainly a surgical pathologist, who by the way is a medical doctor with several years of post doctoral subspecialty training in anatomic pathology. The language and associations are about what I would have responded. And yes, I also am a surgical pathologist, one who reads a lot of bowel biopsies.