Colorectal Flashcards
Most common site of metastasis of Colon Cancer
Liver
Symptoms of Colorectal cancer
Melena/Hematochezia
Alternating constipation and diarrhea
Pencil thin stools
Tenesmus
Loss of weight
Anemia Sx
Causes of pyoderma gangrenosum
- IBD
- Haem malignancy
- Granulomatosis with polyangiitis
- IgA?
What investigation after strep bovis endocarditis
Colonoscopy as it’s a/w colon cancer
Modified and original Amsterdam criteria
3 2 1 rule
3 relatives with Colon(OG) or non colon(modified) Ca
2 successive generations
1 diagnosed before age 50
Risk factors for anal SCC
- HIV and HPV infection
- Immunocompromise
- Receptive anal intercourse
- Smoking
T staging of Colon and Rectal ancer
Tis: Carcinoma in situ, intramucosal
T1: Invades submucosa
T2: Invades muscularis propria
T3: Invades into pericolorectal tissues
T4a: Invades through parietal peritoneum
T4b: Invades or adheres to surrounding organs
Type of IBD that causes lead pipe appearance
UC
Hinchey classification
1a: pericolonic phlegmon
1b: abscess
2: retroperitoneal abscess
3: Purulent peritonitis
4: Feculent peritonitis
Main features of Crohn’s disease
- Transmural with skip lesions,cobblestone
- Mouth to anus
- Strictures, fistulation and malabsorption
Type of IBD a/w rose thorn appearance and string of pearls(Sign of Cantor) on barium enema
Crohns
-deep linear ulcerations
Dx of short gut syndrome
- Malnutrition
- <100cm
diagnosis of Gardner’s syndrome
FAP + Extraintestinal manifestations
Definition of high output stoma
> 1litre
FAP vs attenuated FAP vs Gardners
Gardner’s : FAP + extraintestinal
FAP: CRC before 40yo
Attenuated FAP: CRC after 40yo
What is Chilaiditi syndrome
Transposition of bowel between liver and diaphragm
- May mimic pneumoperitoneum
Options for treatment for obstructed Colorectal Ca
3S
-stent
-stoma
-surgical excision
Spigelman classification is for
Familial adenomatous polyposis
What to look for in a DRE for rectal tumor
- Location of tumor
- Distance of tumor from anal verge
- Mobility
- Ability to get over tumor
- Whether tumor can be cannulated
- Anal tone for sphincter involvement
Invx for newly diagnosed Rectal Ca
- MRI Rectum
- TransRectal US
- CT AP
Most common site of mets for low rectal tumor
Lung: Venous return in via inferior rectal artery which goes to IVC then lung
Colorectal cancer T staging
Tis: Carcinoma in situ, intramucosal
T1: Invades submucosa
T2: Invades muscularis propria
T3: Invades through muscularis propria into subserosa/ pericolorectal tissues
T4a: Invasion through parietal peritoneum
T4b: Invasion/ Adherence to adjacent structures/organs
Mx for anal fistula
- Cutting seton placed
- After fistula migrates to external sphincter, fistolotomy
Mx for anal fistula
- Cutting seton placed
- After fistula migrates to external sphincter, fistolotomy
Reason for spouting ileostomy
Contents are liquid, will swirl around and cause dermatitis
Spot recognition of operation creating an end colostomy with midline laparotomy
Hartmann’s procedure
Spot recognition of operation creating an ileal conduit and an end colostomy
Pelvic exenteration
Principles of treating enterocutaneous fistula
- Sepsis
- Nutrition
- Rule out distal obstruction
- Reduce fistula output( Loperamide, fybogel)
What is a subtotal colectomy
Total colectomy sparing the sigmoid colon
Classification systems for perianal fistulas
- Park
- Goodsall rule
Key numbers for fecal calprotectin test
<100: IBD unlikely —> normal FC has a high negative predictive value
100-250: refer gastro
>250: urgent referral to gastro
Sites of biopsy for suspected IBD
Terminal ileum
Ascending Colon
Transverse Colon
Descending Colon
Rectum
