Our topic now is colon cancer.
It is the second most common cancer in US.
A hundred thousand new cases annually, 6% of the population.
Actually, I thought this was number three?
Yeah, it is. What do you mean? How can it be both? Listen.
If you were to separate the genders and the sexes, males and females.
Mortality males: number one lung cancer,
number two prostate and number 3 colorectal cancer.
Females mortality: number one lung cancer, number two breast cancer,
number three colorectal cancer.
So, you just tell me the third correct? But if you combine your genders.
Oh, second most common cause of cancer in the US. Okay? It is up there.
Age greater than 40. Low fiber, high fat diet.
Personal history of colonic adenoma or cancer.
History is big, long standing such as inflammatory bowel disease
especially ulcerative colitis. No joke.
Family history of sporadic colon cancer and HNPCC,
hereditary nonpolyposis colorectal cancer. Nonpolyposis.
Now. Pause here for a second.
I want to bring two things to light here, so that we're clear moving forward.
HNPCC, remember that in colorectal cancer, what do you want to do?
You want to divide this into really two types.
Just like we did for primary gas for adenocarcinoma.
We talked about two types there. We have two types here,
but two type here literally and anatomically location wise.
You are left-sided, right-sided. Left-sided descending colon, right-sided ascending colon.
Genetically, amazingly, pay attention, HNPCC,
hereditary nonpolyposis colorectal cancer,
but remember by chemistry microcell instability you've heard of MLH and MSH and such,
that will give rise to much more so right-side of colorectal cancer. Memorize that.
Whereas if it's familial adenomatous polyposis.
Then it will be left-side colorectal cancer.
What do you know about FAP? 100% percent are going unto colorectal cancer.
No joke. Know the genetics here big-time.
Diagnoses: Slow growing tumor may present as iron deficiency
especially if it is right-sided. Could you find blood with left-sided?
Remember, you've heard of napkin ring? Or circumferential?
So, you have a ring around the napkin squeezing the ?napkin.?
The ?napkin? is the colon, left-sided.
The descending colon you're squeezing, strangulating it, is that clear?
That is left-sided. So, the circumferential pattern,
the napkin ring is the left side upper core. Once again.
Could you find breathing there? Sure, but that's more altered bowel habit.
On the right side, we will talk about the description, it is called polypoid.
And with the polypoid much more so involved with bleeding and iron deficiency.
Abdominal pain, change in bowel habits much more so with left sided.
Perforation is a complication you worried about and rectal bleeding
obviously will be taking place with both, but much more so with right
and therefore iron deficiency. Your test for diagnosis include colonoscopy
is the test of choice here. Remember that colonoscopy you wanna use prudently
in a patient that may then present with diverticular disease acutely,
but in colorectal cancer, my goodness, it is detested choice.
Barium enema will show you better pictures to what's going on
and your tumor marker, not sensitive but prognostic evaluation is important,
known as CEA, carcinoembryonic antigen,
and of course, some of the new things that you wanna pay attention,
colorectal cancer include your caress and what management
remember not only would you have drugs such as your leucovorin and company,
but then you have a drug called infliximab,
which is then addressing your receptor tyrosine kinase.
Those are molecular pharmacology that you want to be familiar with.
Let us talk about colonoscopy in colon cancer test of choice.
With the coloscopy, very rarely would they ever ask you anything about sigmoidoscopy
because if you were to only do and examined or investigate the sigmoid
or what if you had a cancer on the right side?
What if you had a polyp on the right side, you would miss it completely,
that makes no sense when you know for a fact that it is the second leading killer overall,
third leading killer individually in genders,
so therefore never chose sigmoidoscopy when you are dealing with a colonoscopy.
You do a full colonoscopy to make sure that you catch anything on the right side.
This particular lower colonoscopy is showing you decreased caliber
of the lumen of your colon and you see a little bit of blood as well.
You notice here with this colonoscopy that you would have altered bowel habits
as you are coming down the descending limb.
The left side, will show you what is on the circumferential.
The left side often times referred to as being your apple core,
and you might have heard of this being used, a napkin ring.
Colon cancer prognosis, it is important that you pay attention at staging.
On your boards now a days, whatever board that you are taking,
understand the staging becomes important because it tells you,
well, prognosis goes from relatively maybe decent to absolutely poor.
This staging that we have here for colon cancer is called Duke?s staging.
If it's A: limited to submucosa, there is not much invasion,
you have 95% fibrous survival rate. If it is B: below the submucosa
without regional lymph node involvement, it drops down to maybe 70-85.
Now, take a look at this. We go from submucosa
and you involve the lymph node, you just dropped from 95 down to 55,
and maybe even perhaps 20.
You wanna know the changes on the Duke?s staging from A-C.
Once you get to D? You are gone.
What that means is that metastasis taking place and with colorectal cancer
it can either choose hematology or lymphatic spread.
And if it chooses hematogenous spread,
therefore the number one place of metastasis to colon to the liver.
Right? Colon to the liver. From the liver then maybe perhaps up into the lungs.
Management: Surgery with wide resection, adjuvant chemotherapy,
radiation therapies especially when you start getting into Duke?s staging B as in boy.
Preventions: Screening, screening, screening.
Age 50 years of age and general population keep in mind because of low fiber,
high fat diet type of issue. Age 40 years, ten years prior to diagnosis,
if you are thinking about the patient and the relative is in fact affected.
Ten years younger so kind of behaves like your mammography
in a female with breast cancer, doesn?t it?
Beginning in 8 years if you are thinking about a patient
with inflammatory of bowel disease of the ulcerative colitis type.
Prevention: Test for screening?Colonoscopy, occult blood testing,
barium enema, and virtual colonoscopy,
now a days or course is playing a major rule.