Colorectal + pancreatic cancer Flashcards
colorectal, pancreatic
Cancer
What is a cancer?
A disease caused by an uncontrolled division of abnormal cells in a part of the body
Cancer
What is a primary cancer?
Arising directly from the cells in an organ
Cancer
What is a secondary cancer / metastasis?
Spread from another organ, directly or by other means (blood or lymph)
Cancer
What is a CUP?
Carcinoma of unknown primary (CUP) is a rare disease in which malignant (cancer) cells are found in the body but the place the cancer began is not known
GI Cancer
What kind of epithelial cells do we have in the GI tract?
squamous
glandular epithelium
GI Cancer
What kind of neuroendocrine cells do we have in the GI tract?
enteroendocrine cells
interstitial cells of Cajal
GI Cancer
What kind of connective tissue do we have in the GI tract?
smooth muscle
adipose tissue
GI cancer
What kind of cancer do squamous cells of the GI tract make?
squamous cell carcinoma (SCC)
GI cancer
What kind of cancer do the glandular epithelium of the GI tract make?
adenocarcinoma
GI cancer
What kind of cancer do enteroendocrine cells of the GI tract make?
neuroendocrine tumours (NETs)
GI cancer
What kind of cancer do interstitial cells of Cajal of the GI tract make?
gastrointestinal stromal tumours (GISTs)
GI cancer
What kind of cancer does smooth muscle of the GI tract make?
leiomyoma / leiomyosarcomas
GI cancer
What kind of cancer does adipose tissue of the GI tract make?
liposarcomas
GI cancer
What is the most common GI cancer in western societies?
colorectal
Colorectal cancer
At the start of what age do colorectal cancers start occurring?
Generally affects patients > 50 years (>90% of
cases)
Colorectal cancer
The majority colorectal polyps are ____. The majority of colorectal adenocarcinomas arise from ____.
The majority colorectal polyps are adenomas. The majority of colorectal adenocarcinomas arise from existing adenomas.
Colorectal cancer
What familial syndromes predispose people to colorectal cancer?
- Familial adenomatous polyposis (FAP)
- hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome)
- Peutz-Jegher’s syndrome
Colorectal cancer
What is FAP?
- full name
- mutation involved
- how it presents
- Familial adenomatous polyposis
- Autosomal dominant mutation in chromosome 5 of the APC gene
- Hundreds of polyps within the large intestine and rectum
- Inevitable development of colorectal cancer without total colectomy
Colorectal cancer
What is HNPCC?
- full name
- mutation involved
- how it presents
- Hereditary non-polyposis colorectal cancer
- Autosomal dominant mutation in DNA mismatch repair genes (variable penetration)
- Type 1: hereditary colorectal cancer
- Type 2: as above, with the addition of extra-colonic adenocarcinomas – particularly endometrial carcinoma
Colorectal cancer
What is Peutz-Jegher’s syndrome?
- mutation involved
- how it presents
- Autosomal dominant mutation in STK11 gene
- Multiple hamartomatous polyps throughout the gastrointestinal tract
Colorectal cancer
What histology does colorectal cancer have?
adenocarcinoma
Colorectal cancer
Colorectal cancers develop throughan accumulation of mutations.
Describe the progression from a normal epithelium to a colon carcinoma and the mutations that cause this progression
- normal cell -> APC gene mutation
- hyperproliferative cell -> K-ras mutation
- adenoma -> DCC gene mutation / p53 gene inactivation
- carcinoma
Colorectal cancer
What is an alternative staging system to TNM?
Duke’s classification
Colorectal cancer
How does TNM staging work for colorectal cancer?
(every t passes through a new layer)
Colorectal cancer
What local complications are associated?
Local complications include obstruction, perforation and fistula formation.
Colorectal cancer
How do they spread?
lymphatic, hematogenous or transcoelomic.
Colorectal cancer
Name some risk factors for colorectal cancer:
- past history
- family history
- diet / environmental
Colorectal cancer
The clinical presentation of a colorectal cancer is dependent on its location. Where do colorectal cancers usually occur?
Colorectal cancer
If a colorectal cancer is on the caecal & right side what clinical presentations may there be?
- Iron deficiency anaemia (most common)
- Change of bowel habit (diarrhoea)
- Distal ileum obstruction (late)
- Palpable mass (late)
Colorectal cancer
If the cancer is on the left side & sigmoid carcinoma what clinical presentations may there be?
PR bleeding, mucus
thin stool (late)
Colorectal cancer
If the cancer is a rectal carcinoma what clinical presentations may there be?
- PR bleeding, mucus
- Tenesmus
- Anal, perineal, sacral pain (late)
Colorectal cancer
What is Tenesmus?
The feeling that you need to pass stools, even though your bowels are already empty.
Colorectal cancer
If there is local invasion of the colorectal cancer, what clinical presentations may there be?
- Bladder symptoms
- Female genital tract symptoms
Colorectal cancer
If there is metastasis of the colorectal cancer, what clinical presentations may there be?
- Liver (hepatic pain, jaundice)
- Lung (cough)
- Regional lymph nodes
- Peritoneum (Sister Marie Joseph nodule)
Colorectal cancer
What is this? Why does it appear?
Sister Marie Joseph nodule
an intraperitoneal cancer: tumour metastasised to umbilicus
Colorectal cancer
How can we examine for signs of a primary colorectal cancer?
- Abdominal mass
- DRE
- Rigid sigmoidoscopy
- Abdominal tenderness and distension – large bowel obstruction
Colorectal cancer
What are some signs of metastatic colorectal cancer?
- Hepatomegaly (mets)
- Monophonic wheeze
- Bone pain
Colorectal cancer
What are some faecal occult blood investigations for colorectal cancer?
- Guaiac test (Hemoccult)
- FIT (Faecal Immunochemical Test)
Colorectal cancer
What is a FIT test and what is it used for?
Faecal Immunochemical Test
detects minute amounts of blood in faeces (faecal occult blood)
Colorectal cancer
What is Guaiac test (Hemoccult)?
How sensitive and specific is it as a test?
What are some restrictions patients must follow before having the test done?
based on pseudoperoxidase activity of haematin
Sensitivity of 40-80%; Specificity of 98%
Dietary restrictions – avoid red meat, melons, horse-radish, vitamin C & NSAIDs for 3 days before test
Colorectal cancer
What kinds of blood tests can we do to investigate for colorectal cancers?
- FBC: anaemia, haematinics – low ferritin
- Tumour markers: CEA which is useful for monitoring, but it is not a diagnostic tool!
Colorectal cancer
What imaging investigations may we do to investigate for colorectal cancer?
- colonoscopy
- CT colonoscopy / colonography
- MRI pelvis
- CT chest / abdo / pelvis
Colorectal cancer
What size of lesions can colonoscopies and CT colonoscopies visualise?
- colonoscopy: <5cm
(small polyps can we removed during procedure) - CT: >5cm
Colorectal cancer
Which requires sedations and which is more invasive:
colonoscopy / CT colonoscopy?
colonoscopy more invasive and requires sedation
Colorectal cancer
When may we use an MRI pelvis for colorectal cancer?
for rectal cancer: investigate depth of invasion
to choose between preoperative chemo or straight into surgery