This polyp was found in the sigmoid.
HOW IS IT BEST REMOVED?
■ Cold snare polypectomy
Wouldn't be my first thought!
■ EMR
I agree - single fragment EMR!
■ ESD
Would just add time and expense to procedure (unless you need practise, I guess)
explanation
This 10-12mm polyp is covered with a beautiful gyrate crypt pattern typical of a TVA. The risk of cancer deep within, in spite of the normal surface is far below 1%. But it's not 0% and it would also be a little difficult to cut through this amount of tissue. For these reasons, I think that 'cold snaring' would be wrong.
At the other end of the spectrum, we have an ESD. It would ensure a single fragment resection but would take about 20 minutes or so. The in between the two, we have an EMR. If course, a single injection of 3-4ml would lift this nicely and then a 15mm snare would resect it, single fragment, within a minute. I think that the best method of removal of polyps up to about 2cm, is by EMR as polyps up to this size can usually be removed as a single fragment. These three polyps were removed en-bloc from the proximal colon. In an earlier examination 2 SSL's had been removed. A subsequent colonoscopy finds no further polyps. WHAT WOULD YOU ADVISE AS REGARDS SURVEILLANCE?
■ There is no need for surveillance
You may be right if the patient is old and with multiple comorbidities!
■ Surveillance every 2 years
Yes, this is what guidelines usually recommend for 'SPS'
■ Surveillance every 5 years
Too long if pt fulfills WHO criteria for SPS
explanation
If course, this patient has 'Serrated Polyposis Syndrome'. It's important to recognise that the serrated polyp count is cumulative over multiple colonoscopies. The recently updated 2019 WHO criteria for Serrated Polyposis Syndrome recognize two types of the syndrome: a 'proximal phenotype' with serrated polyps proximal to the rectum, all being ≥5 mm in size, with at least two being ≥10 mm in size (criterion I 2019), and a more 'distal phenotype' with more than 20 serrated polyps of any size throughout the large bowel (criterion II 2019) [Gastroenterology 2020;158:1520–23]. Personally, I believe that there are more than two subtypes of the Serrated Polyposis Syndrome. There is accumulating evidence that the syndrome includes multiple conditions with variable phenotypes and with different risks of progression to CRC [Gut 2010;59:1094–1100]. This would explain the huge range of cancer risk (25%-70%) in published studies [GIE 2016;83:563–65]. Of course, the likely mixture of several 'syndromes', makes writing guidelines difficult. A recent consensus update by the US Multi-Society Task Force recommend offering a follow-up colonoscopy to average risk patients based on number and size of the SSL's found [GIE 2020;91:463–85]. Interestingly, the US guidelines make a distinction between 'hyperplastic polyps' and 'sessile serrated polyps' although pathologists can't reliably make that distinction. Furthermore, the guidelines excludes patients with an increased life-time risk of cancer which of course excludes patients with Serrated Polyposis Syndrome. I find it all somewhat confusing! James East's BSG guideline 2017 [ Gut 2017;0:1–16 ] recommend surveillance every other year whilst the more recent BSG/ACPGBI guideline of 2020 [ Gut 2020;69:201– 23 ] would seem to suggest 3 yr for all 'high risk cases. But these guidelines expressively don't cover pts with hereditary cancers. Hereditary cancers are instead covered by the BSG/ACPGBI 2019 guideline [ Gut 2019;0:1–34 ] which recommends annual surveillance until all polyps are cleared and then every 2 years. Finally, I admit that I also take the age of the patient into consideration as well as the presence of both serrated and adenomatous polyps. A 40 year old person is surely more likely to benefit from surveillance than a 75 year old person with multiple comorbidities? In particular, I would worry about a young patient, perhaps 35 year old, with 1-2 large serrated polyps and perhaps only a single adenoma. Current guidelines don't flag these individuals up but personally, I would organise another surveillance colonoscopy in a few years time. Clearly, more research is needed to unpick the different serrated sub-pathways ! This lesion was found in the sigmoid. You have magnification, NBI, dye spray and lift to help you decide. WHAT IS THE STAGE OF THIS CANCER?
■ Intramucosal
There is no such thing!
■ sm1 invasion
You can see a disorganised crypt pattern?
■ sm2 invasion
That was my guess!
■ sm3 or 'massive' invasion
I think that the lift is better than that!
explanation
I think that it's difficult to tell the difference between no crypt pattern at all and a severely disrupted crypt pattern. Of course, when the crypt pattern is 'severely disorganised' but some of it is still visible, the lesion will be sm1 or sm2. In contrast, if there is no crypt pattern at all, the lesion is sm3 or beyond (the Japanese call this 'massive invasion'). Instead, I rather rely on the degree of lifting. In this case, the endoscopist decided that the lifting was insufficient for a resection and backed off, referring the patient to our MDT. Biopsies confirmed that the lesion was likely to be malignant and the patient ended up with sigmoid resection. I think that there is some sort of crypt pattern in the centre of the lesion. Furthermore, looking at the slight degree of lifting, my guess would be that the lesion is sm1 or sm2 and therefore potentially endoscopically resectable. Actually the cancer turned out to be sm2 (T1,N0). These polyps are found in a rectal pouch WHAT IS THE UNDERLYING DIAGNOSIS?
■ Serrated polyposis syndrome
Polyps is SPS are flat (usually)
■ FAP
Looks like a classic example of rectal surveillance in FAP but polyps do look odd don't they?
■ Juvenile polyposis
Yes! Pt had already developed a CRC and after a subtotal colectomy offered rectal surveillance
explanation
These polyps have a funny crypt pattern, but THERE IS A PATTERN! Accordingly, they are likely to be 'hamartomatous' (a non-sensical histological term which basically means overgrowth of normal tissue). Of course, this patient has Juvenile Polyposis syndrome. Although the polyps are 'hamartomatous', as in Peutz-Jeghers syndrome, there is a stark difference. The polyps in JP often turn dysplastic and are presumably the origin of this patients adenocarcinomas. In contrast, the polyps in PJS are extremely rarely reported to harvest dysplasia (I've never seen a dysplastic polyp in PJS). By the way, the WHO criteria for diagnosis of juvenile polyposis syndrome are one of either:
This polyp was found in the transverse colon of a 60 year old man. WHAT IS THE LIKELY HISTOLOGY OF THE LESION?
■ Serrated polyp
Crypt openings look a little serrated but nothing else does!
■ Adenomatous polyp
This is not an adenomatous crypt pattern!
■ Hamartomatous polyp
When in doubt, it's hamartomatous !
■ Malignant polyp
The crypt pattern is too organised and regular for cancer!
explanation
Sadly, an intimate knowledge of the Kudo crypt patterns doesn't help you here! Adenomatous polyps should be covered with one of the following;
In this case, the closest match is of a serrated polyp, which have wide open crypts with a somewhat jagged outline. However, apart from the crypt openings, there is nothing on this which looks like a serrated polyp! If you can't see a crypt pattern, the lesion is likely to be malignant. Conversely, if the lesion does have crypts but still doesn't look familiar, its either a hamartomatous polyp or, perhaps less likely, a 'Traditional Serrated Adenoma'. This lesion turned out to be a hamartomatous polyp. Why a 60 year old man would grow a hamartomatous colonic polyp remains a mystery ! This is beautiful polyp, perched on a fold, was found at the junction between the caecum and the ascending colon. The video gives you a better idea of the size and extent of the lesion. WHERE WOULD YOU PLACE THE NEEDLE FOR THE BEST 'LIFT' ?
■ On the side facing you
A convenient choice but lift will not be optimal
■ Into the apex of the polyp
That would be my choice!
■ Just behind the lesion
Better than into the fold facing you
explanation
I have no qualms about injecting straight into the middle of lesion provided that I'm sure that it's benign. The lovely gyrate pattern of this polyp tells you that it's a TVA, likely to harbour no more than LGD. Injecting into the fold facing you is likely not to raise the 'blind side' of the polyp which extends down the back of the fold and onto the 'flat' beyond. Conversely, injecting into the back of the lesion would lift the back end but probably not the front. My choice was to inject into the apex (see video below) which resulted in a lovely lift. But, why not inject in two places? Because you should try to avoid injecting into more than one place (if it can be avoided). If you have made more than one hole in the epithelium you may will find that your injection leaks out through the previous hole and that the elevation is less effective. Of course when removing large, flat lesions multiple injection sites can't be avoide, unless you are removing the lesion by ESD of course.
This small polyp was removed from the transverse colon. H&E histology is attached
WHAT IS THE DIAGNOSIS?
■ Serrated polyp
Crypt pattern looks more adenomatous!
■ Adenomatous polyp
Slit-like crypts but that thick capillary doesn't fit!
■ Leiomyoma
You're good at histology!
■ Neuroendocrine tumour
That was my guess too but I was wrong!
■ Small CRC
This lesion is submucosal!
explanation
I was quite sure that this was a small NET. It's that vessel crawling up it's side which convinced me. The reason that I enclose the histology is because it's not a neuroendocrine tumour! Histology shows interlacing bundles of spindle-shaped, smooth muscle cells. with bland-looking nuclei probably arising from the muscularis mucosa just below the epithelium.
It's a leiomyoma, which are very uncommon in the colon but of course very common in the oesophagus. Endoscopically, it's usually not difficult to tell the two apart. NET's often have a dip in the centre and/or sizeable vessels crawling up their sides. Colonic leiomyomas are usually covered with entirely normal looking epithelium. With immunohistochemistry it's easy to tell the two apart. A GIST (thought to arise from the 'interstitial cells of Cajar') usually stain with c-kit (CD117) while a leiomyoma is (thought to originate from smooth muscle cells) stain positive for smooth muscle actin or desmin, but not for c-kit. Of course leiomyomas are subepithelial lesions, covered with a normal mucosa. The differential diagnosis of submucosal swellings in the colon include:
This sessile polyp was found in the caecum, close to the appendiceal orrifice WHAT IS YOUR DIAGNOSIS?
■ Mixed adenomatous & serrated polyp
I don't see a mixture of crypt patterns!
■ SSL
Absolutely!
■ TSA
No, TSA's look like a cross between TVA & VA!
■ Adenomatous polyp
Perhaps the crypts look a little slit-like but it's covered with mucus...
explanation
Well, perhaps the crypt openings look a little slit-like but the lesion is partially covered with that mucus typical of an SSL. By the way, couldn't it be a hyperplastic polyp? I think that pathologists have given up even attempting to tell the two apart! My own rule of thumb is that anything which is ≥10mm, I call an SSL and remove. By the way, SSL's usually lift very well. In this particular case, the lift is a little sub-standard for an SSL, presumably because it's situated very close to the appendix orifice which anchors it down. A word of caution! I've had several 'post polypectomy syndrome' cases after removing large SSL's. In these cases, the lift was excellent and I asked for the LARGE snare to remove the lesion en-bloc. However, in both cases, I found that the snare was taking quite a long time to cut through. Perhaps because of that fatty reaction in the stroma below which Neil Shepherd talked about in the Podcast. To avoid any risk of the 'post polypectomy syndrome', you should ask your assistant to close the snare as quickly and hard as possible. Don't worry about bleeding. These lesions are never supplied by any significant vessels. Oh yes! And place clips !!! This 80 yr old man was first referred for a CT to investigate his PR bleeding and mucus. The CT reported that the rectum appeared thickened and a Flex Sig is organised WHAT IS YOUR DIAGNOSIS?
■ Active proctitis with inflammatory polyp
That was my diagnosis and I was half correct!
■ Active proctitis with adenomatous polyp
Very good call!!! Better than mine if fact!
■ Circumferential polyp with dominant nodule
Apologies for the indigo carmine dye which has confused you!
■ Circumferential polyp with malignant change
The blue dye is confusing and the proctitis does look weird in places
explanation
Yes, it does seem odd to refer for a CT rather than a Flex Sig? Perhaps this was because the patient was 80 yrs old or because of our endoscopy waiting list. Anyway, I was half correct. I diagnosed an active colitis and histology confirmed a: transmucosal inflammation with crypt abscess and focal epithelial loss (tiny, tiny ulcers). We all know that active colitis is characterised by an dull erythema, bleeding and erosions/ulcers. The best endoscopic scoring system is currently the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) which scores these three parameters on a scale of 0 to 3. There are other scoring systems of course such as the Mayo score, the Baron score, The Rachmilewitz Endoscopic Index, The Sutherland Index, The Matts Score, The Blackstone Index and the most recent addission, The Ulcerative Colitis Colonoscopic Index of Severity! Of course this tells you than none of them is the last word on the topic. For a good review of all endoscopic issues relating to colitis, please check this article out; Annese V. European evidence based consensus for endoscopy in inflammatory bowel disease, J Crohn's Colitis 2013;7(12);982-1018 Anyway, I find it odd that other common features of an active colitis are not included in any of these scoring systems. This includes mucosal oedema, a villous epithelial surface (as seen in this video) and a mucopurulent discharge (which I regard as feature of a severe attack of colitis). These three features are prominent in this video and if not recognised as features of an active colitis, can be mistaken for a neoplastic process. I thought that the nodule would be inflammatory but it turned out to be a 'TSA' (traditional serrated adenoma), the most rare and elusive of all colorectal polyps. Well I blame the inflammation and that thin mucopurulent layer obscuring the crypt pattern. This polyp just distally to the caecum has been referred after an initial set of samples have indicated that it's a benign TVA harbouring no more than LGD. An unfortunate, fixed loop at the hepatic flexure means that I can't retrovert behind this polyp. In fact, it's difficult to get much closer to the lesion than this. WHAT STATEMENT DO YOU AGREE WITH?
■ The resection may be difficult but it can be done
I agree with that!
■ The location of the lesion and difficult colonic configuration probably makes a resection impossible
Of course the patient may have to travel to a nearby centre with the neccessary expertise!
■ All this is irrelevant as the polyp looks suspicious and would be best removed surgically
I disagree, it does look benign! But will of course have a 15% risk of harbouring cancer...
explanation
Actually, the lesion does look very benign. It wobbles about freely perched on top of the first fold distally to the caecum. Furthermore, it has a reassuring gyrate crypt pattern of a TVA. Naturally, any polyp of this size will have a 15% risk of actually containing an unexpected focus of cancer within. Because our therapeutic waiting list is in mess in the aftermath of Covid, I do encourage everyone to sample the sessile lesion even though you are planning to refer it for resection. Such sampling on the surface of large sessile lesions doesn't induce any fibrosis and provides some (limited of course) reassurance that the lesion isn't malignant. In this case, the position is very challenging but you can get close enough to stand a good chance of removing the lesion. That's actually what I did and I've just uploaded a video of the resection together with my face-to-camera annotation to highlight the main points. Ultimately, histology confirmed a TVA harbouring no more than LGD This subcentimetere polyp was discovered in the rectum of a 60 year old woman undergoing a bowel cancer screening colonoscopy following a positive FIT. Considering the endoscopic appearance and the degree of lifting, WHAT WOULD YOU DO?
■ This is a benign adenoma but it's too close to a large vein for removal
Don't worry about the vein!
■ This is a benign adenoma which I would remove
Doesn't look benign!!
■ This is a likely early cancer which I would remove
Yes it looks evil but should you attack?
■ This is an invasive cancer which I would only sample
Can't argue with that!
explanation
That vein looks intimidating but don't be intimidated! It's not a 'show stopper'. it will move out of the way. However, that polyp does look nasty as there is no definite crypt pattern in the centre, just a swirly surface. However, the lifting is good, suggestive that we stand a good chance of clearing the lesion endoscopically ...
And at this point you can either go ahead and remove the likely early cancer. The advantage is that you get the correct diagnosis whilst biopsies are often inconclusive. The reason why surface biopsies are often unable to confirm invasive cancer is because your pathologists rely on seeing invasion of malignant tissue below the muscular mucosa. The underlying muscularis mucosa is usually NOT included in surface biopsies. However, this is a good example of the potential disadvantages of going ahead to resect the lesion. As you'll see in the video below, I removed it. Histology reported that the lesion was indeed an early rectal carcinoma, 6mm in diameter and with clear margins. However, the deep margin was 'only' clear by 200 microns which of course our pathologists would call a 'positive deep margin'. A 1mm (that is 1000 micron) is the 'accepted' definition of a 'clear surgical margin'. Secondly, there was of course a small focus of LVI. There is usually something to keep you awake at night after removing an early cancer. The disadvantage is obviously that you don't know what to tell the patient!!! - Is my cancer gone or not? - I'm sorry but I'm not sure! - Couldn't you keep a close eye on me with regular colonoscopies and CT's? Well, we could but there is absolutely no evidence that this will save your life IF you still have cancer cells inside of you... Fortunately, there is a study under way in the Netherlands to answer this very question! At the moment, we know that LVI is 'bad' and that the normal next step would be to offer the patient surgery. This is the sigmoid colon and rectum of a young patient who have just undergone bone marrow transplantation. WHAT IS THE LIKELY DIAGNOSIS?
■ Graft versus host disease
You don't get ulcers in GVHD!
■ Checkpoint inhibitor colitis
You DO get ulcers with these but they wouldn't be used!
■ Pseudomembranous colitis
Doesn't cause ulceration
■ CMV colitis
Absolutely !
■ Herpetic colitis
Hmm, does this actually happen?!
explanation
In GVHD there are minimal mucosal changes whilst there is extensive ulceration in this case. You do get nasty mucosal ulceration with checkpoint inhibitors but these drugs would not be used in transplantation. C.diff doesnt' cause mucosal ulceration and the herpes virus does not infect columnar mucosa. This leaves CMV ! Cytomegalovirus is a herpes virus that infects the majority of humans. Primary infection in individuals with normal immune function is usually asymptomatic or result in mononucleosis-like syndrome (fever, lymphadenopathy, and atypical lymphocytosis on a blood film). After primary infection, CMV becomes latent in various host cells but are controlled by a functioning immune system. When re-activation occurs in patients with severely compromised immune function (transplant patients or patients with AIDS and CD4 count <50 cells/microlitre), uncontrolled CMV replication can ensue leading to fever, bone marrow suppression, and tissue-invasive disease, depending on where the reactivated cells are residing. Investigations includes serology, pp65 antigenaemia test, histopatholical analysis of any tissue obtained, and PCR based detection. Treatment of choice is oral valganciclovir or intravenous ganciclovir whilst IV foscarnet and cidofovir are second line agents.
This is the sigmoid mucosa of an elderly inpatient who has developed diarrhoea.
WHAT SINGLE TEST WOULD YOU RECOMMEND NEXT?
■ FBC
Of course it's not sensitive nor specific and does not exclude diagnosis if normal. Nevertheless, a very high WBC level is often found in fulminant pseudomembranous colitis.
■ Obtain a set of stool cultures
Probably not a priority and they should have done it already!
■ ELISA for C.diff toxin in the stool
Yes! Results available within a few hours with sensitivity of 65%-85% and specificity 95%-100%
■ Stool PCR for C.diff
Seems like a sensible investigation in patients with unexplained, new-onset diarrhoea but perhaps not the single most important test...
■ Abdominal X-ray
Important IF there is significant abdominal distension
explanation
Of course this is a case of Clostridium difficule associated colitis (pseudomembranous colitis). Patients usually present with diarrhoea, abdominal pain, and leukocytosis, and a history of recent antibiotic use. Other common symptoms include fever, abdominal tenderness, and distension.
In a symptomatic patient with typical colonic pseudomembranes such as in this case, arguably it would be sensible to recommend that treatment is immediately started. Stool testing should be considered in any patient with unexplained, new-onset diarrhoea (defined as 3 or more unformed stools in 24 hours in a patient not taking laxatives). Your local institution will probably have protocols for how patients should be investigated and all of the above test may well be part of the algorithm. When I was on the wards, toxin tests were favored over culture for diagnosis of C.diff because it was the toxins which mediate disease. detection of toxins was faster and correlated better with symptoms. However, there was a move towards 'molecular tests' (PCR for the bacterium) from 2009 because of concern that patients with C.diff could be missed by toxin tests. Of course, this raised the question; do toxin-negative patients with a positive C difficile PCR test result require treatment? Several studies have now indicated that about half of the patients with positive PCR test for C. diff do not experience adverse events without treatment and do not need treatment. For this reason, PCR testing for C.diff should not be used as the stand-alone diagnostic test. Instead it's patients with clinical disease (diarrhoea) AND a positive toxin assay who should be treated! There are lots of references for this statement and here is an open access article in JAMA: Treatment is to discontinue the responsible antibiotic and start therapy with oral vancomycin or fidaxomicin. Up to 50% of patients have a relapse after discontinuation of antibiotics, but most respond to a second course of therapy. In those who relapse again, faecal microbiota transplantation is very effective.
This is the colon of a 55 year old woman who has been treated for diarrhoea.
WHAT IS THE DIAGNOSIS?
■ Crohn's disease
Possible of course but why a 'middle aged lady'?
■ Ulcerative colitis
Zero points!
■ Microscopic colitis
Of course!
explanation
Actually, this patient had collagenous colitis and after treated with budesonide, symptoms settled. A colonoscopy 3 months later showed these linear scars throughout the colon.
The first case of collagenous colitis was described in 1976 by Lindström and is characterised by chronic watery diarrhoea. Underlying hyperthyroidism, coeliac disease, bile salt diarrhoea and inflammatory bowel disease should be excluded. At colonoscopy, the mucosa is often unremarkable but there may also be mild, patchy erythema or linear cracks. Histology reveals thickening of the subepithelial collagen layer from the normal 3-6 μm to more than 10 μm as well as lymphocytic infiltration of the epithelium and the lamina propria (see image below). Rectal biopsies are not sufficient to make the diagnosis as normally the collagen layer is particularly thin here. Samples from the rectum and sigmoid confirms the diagnosis is more than 90% of cases. 9mg of Budesonide is effective but there is a high risk of relapse on stopping the drug [Bonderup OK. Gut 2003;52:248-51] and azathioprine is usually the second line agent. This lesion was found at the top end of the colon. WHAT WOULD YOU DO NEXT?
■ Lesion is benign but it can't be removed endoscopically
Best to admit defeat than to fight against overwhelming odds
■ Lesion is benign and I will organise an EMR
Not sure that anyone could remove this endoscopically
■ Lesion is benign and I will organise an ESD
Ridiculous!
■ Lesion is benign and I will organise an underwater resection
It will also fail !
■ Lesion is malignant and requires a surgical resection
Polyp is large BUT looks benign!
explanation
This is a classical LST-G (laterally spreading tumour of the granular type). These lesions are always TVA's and almost always harbour LGD. Unfortunately, there are three problems which precluded an endoscopic resection; 1) there is a crazy alpha loop in the transverse colon which as usual proved impossible to remove, 2) the movement of the diaphragm continuously moves the lesion away and towards you and 3) the main part of the lesion is in the ascending colon but then extends across to the caecum where it almost kiss the appendix orifice. The moral of the story is to carefully consider BEFORE you start the resection. After you have started to attempt resecting a lesion such as this it becomes progressively more difficult to stop! It's like a gambler finding it increasingly difficult to walk away from the table as losses stack up. Because you have invested so much time and effort, it becomes difficult to stop and admit defeat! This was found in the sigmoid of a 35 year old lady presenting with abdominal pain and bleeding. She has been taking ibuprofen for her pain. WHAT IS THE MOST LIKELY DIAGNOSIS?
■ NSAID induced colitis
Possible but the pain came before starting the ibuprofen
■ Ulcerative colitis
Stricturing and linerar ulcers are not typical for UC
■ Crohn's disease
Most likely and don't forget to add your endoscopic diagnosis to the histology request form!
■ Diverticular stricture
Those rarely ulcerate and are usually MUCH tighter
■ Malignant stricture
Those post-inflammatory polyps are innocent!
explanation
The superficial, linear ulcers are typical of inflammatory bowel disease. Both ulcerative colitis and Crohn's disease can cause stricturing but of course Crohn's is more likely to. Those little nodules are post-inflammatory polyps, covered in normal crypts. In any case of colitis it's important to take a full set of samples, targeting not only areas which are visibly inflamed but also non-inflamed areas. Patchy inflammation is very suggestive of Crohn's disease but if you neglect to sample the non-inflamed areas, you will find that your pathologists will report a continuous colitis which would be more suggestive of ulcerative colitis. After all, they can only report on the samples given to them and may well not read your endoscopy report. This 75 year old man underwent a CTC because of a change in bowel habit which has confirmed a large caecal polyp. The patient has been referred for a snare polypectomy. WHAT WOULD YOU DO NEXT?
■ Abort the procedure and reassure the patient
Absolutely!
■ Take a full set of samples
Uneccessary and they will only show normal mucosa
■ Remove the polyp by EMR
Foolish!
■ Remove the polyp by ESD
Idiotic!!!
explanation
The location and the 'pillow sign' tells you that this lesion is a lipoma. We know from Shrisha Hebbar's Podcast that the ICV is a high risk location for any attempt at removing lipomas. He mentions a patient of his who presented with acute small bowel obstruction due to engorgement of an ICV lipoma after the placement of an Olympus ligation.
Furthermore, you wouldn't of course go ahead with an attempt at resecting a lipoma without due consideration of indications. How long has the patient had symptoms? Are they getting better? Are symptoms likely to arise because of this soft and floppy lesion. Probably unlikely and statistically speaking, this elderly patient is probably far more likely to have a change in bowel habit due to constipation. By the way, please take notice of the odd looking mucosal crypt pattern which is reminiscent of a TVA! This is the normal crypt pattern at the ICV at the transition to the villous surface in the terminal ileum!
With a magnifying colonoscope and dye, another world is revealed.
WHAT IS SHOWN IN THIS PHOTOGRAPH?
■ Crypt distortion
No, these crypts are MUTATED!
■ Abberant crypt focus
You know your stuff!
■ Small flat adenoma
Histologically, you could be correct!
EXPLANATION
The link between ACF and proximal adenomas, I see as evidence of a colonic “field effect” in which exposure to carcinogenic 'drivers' (dietary, lifestyle, disease and genetic) all work together to prime the colon for the development of cancer. It's for this reason, that endoscopically resecting DALM's (I arbitrarily define DALM's as flat polyps within the colitic field of a patient with >6 yrs of colitis), then telling patients that they now have nothing to worry about, is naïve ...
I found this in the low rectum of an elderly lady undergoing a flexible sigmoidoscopy because of rectal bleeding. A quick check with the patient confirmed my suspicions.
WHAT IS THE DIAGNOSIS?
■ Rectal prolapse
The patient would know about that!
■ Solitary rectal ulcer syndrome
A good guess and patient would know about constipation and straining but actually not the correct answer
■ Likely serrated polyp syndrome
Hmm, what question would you ask patient? FH of CRC perhaps?
■ Likely FAP
Findings of a rectal pouch in FAP? No, that's not it!
explanation
On first glance this looks like a circumferential serrated polyp in the rectum. Of course, this would be somewhat odd and furthermore, unlikely that the patient would know anything about this.
Actually, on direct questioning she did know about her prolapse! Another common endoscopic finding is an erythematous and oedematous patch, close to the anal margin. Just a bit of fun! Above are four types of benign polyps which can be found in the stomach, duodenum and colon respectively. I've used a 'plugin' which will hopefully make it easier to see the polyps on a small screen. BUT WHAT ARE THESE FOUR POLYPS ? A = B = C = D = You'll have to make up your mind and then click 'Explanation' below to reveal the correct answers ! EXPLANATION
The 3 polyps in column A are all adenomatous polyps. Flat and plaque-like in the stomach, pale in the duodenum and a sessile TVA in the colon. Column B shows NET's with the prominent vessels along it's side in the stomach and colon whilst the duodenal NET has the typical central depression. Column C shows 'hamartomatous' polyps seen in Peutz-Jeghers syndrome. There is hardly ever any dysplasia within these polyp and it's uncertain what the 'precursor lesion' is for these patients GI cancers Column D show inflammatory polyps which are typically angry red and sometimes with pretty white spots !
This 70 year old patient with known ischaemic heart disease presents with sudden onset bloody diarrhoea. He undergoes a flexible sigmoidoscopy the following morning and this is what the sigmoid colon looks like. With support and conservative measures symptoms subside and the patient is discharged a week later. However, a week later the patient presents again. Now with hypotension, abdominal distention, fever and a raised white count. An abdominal X-ray is done on admission (below).
WHAT IS THE LIKELY DIAGNOSIS?
■ Colonic stricture
Too soon for this!
■ Another attack of ischaemic colitis
Unfortunately, yes!
■ Pseudomembranous colitis
He didn't actually receive any antibiotics last admission
■ Crohn's disease
Unlikely !
explanation
There is little mystery that the first presentation was due to ischaemic colitis. The second presentation is more tricky. He actually presented with an ileus and pain this time. Actually, the patient had been on aspirin but this had been stopped at the previous admission. This was clearly a mistake as the second presentation turned out also to be due to ischaemic colitis. This time the ischaemic colitis was more severe but he did recover in the end.
After ischaemic colitis about 10% of patients develop and ischaemic stricture but it takes longer than a single week to develop. The hallmark of an ischaemic colitis are areas of longitudinal ulceration, on the anti-mesenteric border (90° to any diverticulum) where the blood flow is the slowest. Of course, endoscopically its difficult to tell where the omental reflection is situated. However, the ulceration will run along one aspect of the colonic circumference. Of course in the epicentre of the ischaemic (typically around the splenic flexure), the ulceration may well be circumferential. Ischaemic colitis is surprisingly easy to confirm histologically as the pathologists look for crypt withering and fibrosis. By the way, if the mucosa looks dusky and there is no bleeding on taking samples, the likelihood is that the colon is turning gangrenous, associated with a >50% mortality rate.
A very odd looking polyp at the anal verge. I removed it but still couldn't really make out what it was!?
WHAT IS YOUR BEST GUESS AT THE MOST LIKELY DIAGNOSIS?
■ Inflammatory polyp
Good guess as there is no crypt pattern!
■ Adenomatous polyp
It has the colour of an adenomatous polyp but no crypt pattern...
■ Small adenocarcinoma
Certainly ugly enough but small carcinomas are usually more button-shaped
■ Small SCC
Arising from close to the anal margin but nearby squamous mucosa is unremarkable...
explanation
This is rare stuff! I was clueless although reassured that the thing was soft and didn't feel malignant when squeezed between my fingers.
It proved to be a (rare) 'cloacogenic polyp'! You'd be excused if you have never heard of this (I hadn't). Apparently these were first described as recently as 1981! The same year that I was born ☺! Essentially they are inflammatory polyps arising from the transitional zone of the anorectal junction. They can be much larger than this and even be multiple and can occur at any age. Patients are usually asymptomatic but could (naturally) present with some blood on the toilet paper (this patients complaint). Histology is similar to that of solitary rectal ulcers with inflammation and fibromuscular hypertrophy. For this reason it is perhaps not surprising that they are linked with constipation and straining. Rare associations include small nearby cancers and human papillomavirus infection. This lesion was found in the ascending colon. WHAT IS THE MOST LIKELY DIAGNOSIS?
■ Lipoma
Hmm looks too translucent
■ Lymphangioectatic cyst
Well it looks cystic doesn't it!!!
■ GIST
I predict that the pillow sign will be positive
■ Serrated polyp
Doesn't look like a polyp
■ Adenomatous polyp
But the crypt pattern is normal !!!
explanation
The apparent lesion is covered with a normal layer of mucosa. In addition, it seems very soft. However, the lesion looks more translucent than yellow! Of course, it's another lymphangioectatic cyst ! Naturally, you confirm this by giving it a prod with your biopsy forceps. If soft, its either a lipoma or a cyst. If firm, it's either a GIST, leiomyoma or a metastasis (I guess).
A 65-year-old man presents with a 1-week history of a worsening low abdominal pain. The abdominal pain was preceded by exertional chest pain that settled with anti-anginal therapy prescribed by the patient’s GP.
Apart from hypertension that is managed with ramipril, the recently started anti-anginal drug nicorandil and low-dose aspirin, the patient is well and able walk several miles without shortness of breath. Routine blood tests are normal on admission and the patient denies taking an NSAID or paracetamol. After the CT above and colonoscopy is carried out showing the above caecal inflammation. Unfortunately, the patient soon deteriorates requires an emergency right hemi-colectomy before histology is to hand. WHAT IS THE MOST LIKELY DIAGNOSIS?
■ Aspirin induced colitis
With 75mg of aspirin ?
■ ramipril induced colitis
Never heard of it!
■ Ischaemic colitis
An unusual but well recognised location but wrong ☺
■ Nicorandil induced colitis
Up to 5% get colitis on this drug
■ Crohn's disease
Nope, that's not it!
explanation
Getting this diagnosis wrong would have profound implications for the patient ! The ulceration would be likely to recur and the patient may even present with further ulceration unless it is recognised that the cause is his nicorandil tablets !
Nicorandil, a combined venous and arterial vasodilator is effectively the drug of last resort for angina. The reason is that there have been numerous reports of ulceration affecting skin, eyes or mucous membranes which have accumulated since the drug was launched in 1994. Small aphthous ulcers are said to occur in up to 5% of patients but more severe, painful and deep ulceration may ensue. In the gastrointestinal tract, perforations, fistula formation and abscesses are recognised complications. Patients taking NSAID’s, steroids or have diverticular disease are at particular risk. There is also some evidence that the risk of ulceration increases with dose and ulceration may be precipitated by an increase in dose. The underlying mechanism by which the drug causes ulceration is unknown. However, nicorandil-induced ulcers persist until the drug is withdrawn although healing may take up to 6 months. In addition to patients with a history of ulceration of mucosal membranes, nicorandil is contraindicated in patients with hypokalaemia, heart failure and renal impairment.
This polyp was found at the apex of the caecum. With some trepidation, a sample was obtained following which I requested the above CT
WHAT IS THE FINAL DIAGNOSIS ?
■ Hyperplastic polyp
Seems unlikely?
■ Inverted appendix
Was my very first thought too!
■ Adenoma
But I can't see a crypt pattern?!
■ Lymphoma
Why do you say that?
■ Mucocoele of the appendix
Was my diagnosis too and why I requested the CT!
explanation
I feel that I should apologise because it's almost impossible to make a diagnosis from the appearance of that appendix. The only abnormality, apart from it being there in the first place, is a subtle nodularity with a normal overlying mucosa. perhaps this rings a faint bell ???
Actually, it turns out that the submucosa is full of small lymphoid cells clusters, forming balls. This is the classical histological appearance of a Mantle Cell Lymphoma? Mantle cell lymphoma has a predilection for the GI tract as the most common extra-nodal site. Indeed, one study found lymphoma in mucosal biopsies in 56/60 patients (both in UGI and Lower GI tract). This has given rise to a theory that mantle cell lymphoma actually originate from gut B-lymphocytes within the mantle zones of mucosal lymphoid follicles [Cancer 2003;97(3):586–91]. Endoscopic findings includes nodules, polyps, ulcers, and masses. I try to remember Mantle Cell Lymphoma if the mucosa appears markedly bumpy - as if the lymphoid follicles have gone crazy! In this case, the CT shows lots of enlarged lymphnodes, both above and below the diaphragm and the patient was started on 'Ibrutinib'. It's not a 'good lymphoma' as median life expectancy is only 6-7 yrs. |
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