Colorectal Flashcards
How would you treat an acute anal fissure?
Assess for red flag features
Stool softeners
GTN 0.2% for 8 weeks (or 2% Diltiazem) –> 60-70% response
If fails EUA +/- biopsy +/- Botox 25 units either side into internal anal sphincter (90% success)
If fails anal manometry and endoanal US
What proportion of colorectal cancers are associated with HNPCC?
-This is Lynch syndrome - about 3-5%
What is the Genetic defect in Lynch Syndrome?
Usually MMR deficiency
What screening should patients with Lynch syndrome receive?
2 yearly colonoscopy from 25-75 for MLH1/MLH2
and from 35 for MSH6/PMS2 mutations
2 yearly OGD from 50
Annual TVUSS and ca125
Annual renal USS
What are the extra intestinal manifestations of Lynch syndrome?
30-70% endometrial cancer
5-10% Gastric cancer
(30-70% Colorectal cancer)
What screening should patients with FAP receive?
Colonoscopy 1-3 yearly from 12-14 until resection.
OGD from 25
What is the mutation seen in FAP?
5q21 APC gene (80%) Autoosomal dominant
What surveillance should be performed in patients ‘at risk’ of APC without an identified APC mutation?
Colonoscopy 5 yearly from 12-14
Where are polyps seen in FAP?
Colonic - 100% - Cancer risk of near 100%
Gastric fundal - 50%
Duodenal 90% - if severe risk of 30% Ca at 10 years)
What eye condition is associated with FAP?
Congenital hypertrophy retinal pigmentation epithelium (CHRPE)
What is Gardner’s syndrome?
FAP + Oestoomas, thyroid cancer, epidermoid cysts and fibromas
Jaw osteomas, extra teeth
What are some indications for surgery in FAP?
Polyps >10mm, HGD, substantial increase in polyp burden
What medical treatments can be used for FAP with intra-abdominal desmoids?
Sulindac + SERM
What surveillance should be conducted for Peutz Jeghers syndrome?
OGD, Colonoscopy and video capsule at 8 years.
Capsule 3 yearly, if polyps also OGD/Colon 3 yearly, otherwise at 18
What is the mutation in Peutz Jeghers syndrome?
STK11 mutation on Chromosome 19 (Dominant)
What types of tumours are most commonly seen in Peutz Jeghers?
Harmartomas
20% risk of CRC and 5% Gastric Cancer
Also breast, ovarian, cervical, pancreatic and testicular
What is the mutation in Cowden disease?
PTEN 10q22
89% Ca any site
81% Breast
16% CRC
Also thyroid and uterine
Some overlap with Juvenile polyposis syndrome
What effect does 5-ASA have on fertility?
80% of males develop sperm dysmotility
What is 6-metacaptopurine (6-MP)
A thiopurine (purine analogue) depressing inflammatory cascade by affecting folic acid and DNA synthesis.
Can take up to 6 weeks for clinical response, 30% of patients are intolerant.
What proportion of patients develop parastomal hernias?
Colostomy - 60%
Ileostomy - 30%
How is a rectal prolapse graded?
Grade 1 - No lower than proximal limit of rectocele
Grade 2 - into rectocele but not top of anal canal
Grade 3 - descends to top of anal canal
Grade 4 - descends into anal canal
Grade 5 - protrudes from anus
What proportion of patients with SRUS respond to biofeedback?
75%
If fails – consider stapled transanal rectal resection (STARR) or VMR
What is the success rate of GTN/Diltiazem for fissure?
20-70%
What medication can reduce the risk of CRC in Lynch syndrome?
Aspirin if taken for >2 years (NICE)