Colorectal

Question 1

What are the names of the two watershed areas of the colon and rectum?

Answer 1

1. Griffith’s point
   
   1. Spenic flexure
   2. Watershed between SMA and IMA
2. Sudak’s point
   
   1. Rectum
   2. Watershed area between the superior and middle rectal arteries

Question 2

How far are the following from the anal verge?

1. Anal canal
2. Rectum
3. Rectosigmoid junction

Answer 2

1. Anal canal is 0-5 cm from the anal verge
2. Rectum is 5-15 cm from the anal verge
3. Rectosigmoid junction is 15-18 cm from the anal verge

Question 3

What marks the transition between the rectum and anal canal?

Answer 3

Levator ani muscles

Question 4

Describe the T Staging for Colorectal Cancer?

Answer 4

T- Tumor stage

T1 - into submucosa

T2 - into muscularis propria

T3 - into subserosa or thorugh muscularis propria if no serosa

T4 - through serosa into free abdominal cavity or into adjacent organs if no serosa

Question 5

Describe the N Staging for Colorectal Cancer

Answer 5

N0 - No nodes positive

N1 - 1-3 + nodes

N2 - 4 or more nodes positive

N3 - Central nodes positive

Question 6

Indications for chemotherapy in Colorectal Cancer

Answer 6

1. Stage III and IV - positive nodes or distant mets (no XRT)
2. Stage II and III Rectal Cancer - neoadjuvant chemo/XRT
3. Stage IV Rectal Cancer - chemo/XRT +/- Surgery

Question 7

What is is the chemotherapy regimen of choice for Colorectal Cancer?

Answer 7

FOLFOX

1. 5-FU
2. Leucovorin
3. Oxliplatin

Question 8

Medical Treatment for Ulcerative Colitis

Answer 8

• Maintenance therapy: sulfasalazine (or 5-ASA) and loperamide
• Acute flares: steroids
  
  • For steroid refractory disease: cyclosporine or inflixamab
• Concern for infection/toxic megacolin: Cipro/Flagyl

Question 9

Symptoms/Signs of toxic colitis and toxic megacolon

+

Treatment

Answer 9

• Toxic colitis: > 6 bloody stools per day, decrease in Hb, leukocytosis, tachycardia
• Toxic megacolon: signs of toxic colitis + abdominal distension, pain, and tenderness

Treatment:

• Conservative: NGT, IV fluids, bowel rest, antibiotics, follow with radiographs and improvement of symptoms
• Surgery: pneumoperitoneaum, diffuse peritonitis, localized peritonitis with colonic distension > 10 cm, uncontrolled sepsis, failure to improve within 24-48 hours

Question 10

Describe the types of internal hermorrhoids

Answer 10

1. Primary: slide below dentate line with straining
2. Secondary: prolapse with spontaneous reduction
3. Tertiary: requires manual reduction
4. Quaternary: cannot be reduced

Question 11

What are the indications and components of the Nigro Protocol?

Answer 11

Indications for Nigro Protocol: Squamous cell carcinoma of the anal canal

Components: Chemo/XRT with 5-FU and mitomycin

Question 12

In difference from SCC of the anal canal, what is standard treatment for SCC of the anal verge?

Answer 12

1. WLE only for lesions < 5 cm (need 0.5 cm margin)
2. Chemo/XRT as primary treatment for lesions > 5 cm to avoid sphincter and APR

Question 13

What is the usual treatment for adenocarcinoma of the anal canal?

Answer 13

WLE possible if: < 4cm, < 1/2 circumference, T1 tumors with 2-3 mm margin possible, well-differentiated, no lymphatovascular/nerve invasion

Otherwise: APR

Question 14

What are the lymphatic drainage patterns of the following areas of the anorectum?

Superior and Middle Rectum

Lower Rectum

Anal Canal

Anal Margin

Answer 14

Superior and Middle Rectum: IMA nodes

Lower Rectum: Mostly IMA + Internal iliac nodes also

Anal Canal: Internal iliac nodes

Anal Margin: Inguinal lymph nodes

Question 15

Summarize the Modified Hinchey Classifications for Diverticulitis

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Treatment

Answer 15