Yet another reason to be paranoid...

This patient underwent a CT angiogram for chest pain. The angiogram was unremarkable but the radiologist mentions an 'irregularity at the caecal pole with hyperenhancement and mild adjacent fat stranding' and recommend colonoscopy. After the examination, your patient asks you if you have found anything?
WHAT WILL YOU TELL YOUR PATIENT

a) Reassure the patient

That would be unwise!

b) Tell him to wait for the histology

Strictly speaking 'not wrong' but it's not the best option to choose

c) Tell him that we will organise an MRI scan next

MRI's are requested for rectal cancers

d) Tell him that we will organise an EUS next

Life is too short for EUS!

e) Tell him that we will organise a 'staging' chest/abdomen/pelvic CT

This is precisely what you should do!

explanation

Did you notice the lesion next to the biopsy forceps? At initial glance into the caecum, there is nothing to see.  However, this lesion was about 20mm in diameter and with that rolled edge.  It's clearly malignant and you need to request staging CT's. Histology did confirm a mucinous adenocarcinoma and CT sized it at 4.7cm.  Far larger than initially thought!  As it was involving the serosal surface, it was staged as T4, N1 (due to several small nearby nodes). 

Mucinous colonic cancers are unusual, accounting for about a little more than 10% of CRC's. They are usually situated in the proximal colon. This is not the only reason why they are easy to miss. At the early stages they have an infiltrative, ulcerative growth pattern which easily hides behind bubbles or a pool.  These are small but evil little things which are easy to miss and grow fast. 

By the way, 'signet ring adenocarcinoma' (where the mucus is INSIDE the cell rather than OUTSIDE of the cells) is another sub-type of adenocarcinoma which may be part of the same spectrum. Mucinous and signet ring adenocarcinoma, share similar molecular features such as MSI-H, CpG island methylator phenotype-high (CIMP-H), and frequent BRAF V600E mutations. Of course microsatellite instability is linked with Lynch syndrome but in this case immunohistochemistry stains revealed normal mismatch repair proteins MLH1, PMS2, MSH2 and MSH6.