Best of 3

1. Colon cancer
Including rt/lt hemi
colectomy,sigmoid & rectal resection

2. Key facts
• Colorectal cancer (CRCa) is the 2nd
commonest tumour and commonest GI
malignancy.
• 1 in 18 of the population will suffer CRCa,
• M:F::3:1.
• Peak age of incidence 45-65 but is increasing
in younger ages.

4. Pathological features
• The predominant type is adenocarcinoma
(mucinous, signet ring cell, and anaplastic
subtypes).
• Classified as well, moderately, or poorly
differentiated

5. Predisposing factors include:
• Polyposis syndromes (including FAP, HNPCC,
juvenile polyposis);
• Strong family history of colorectal carcinoma;
• Previous history of polyps or crca;
• Chronic ulcerative colitis or colonic crohn's
disease;
• Diet poor in fruit and vegetables.

6. Risk Factors Associated with Colon Cancer
RISK FACTORS COMMENT
Geographic variation Highest risk in Western countries and lowest risk in
developing countries
Age Risk increase sharply after the fifth decade
Diet Increased with total and animal fat diets
Physical inactivity Increased with obesity and sedentary life style
Adenoma Risk dependent on type and size
FAP penetrance in gene carriers 100%
HNPCC penetrance in gene carriers 80%
Hamartomatous syndromes Risk increased with Peutz-Jeghers syndrome and juvenile
polyposis but not isolated juvenile polyps
Previous history of colon cancer Increased risk for recurrent cancer
Ulcerative colitis 10–20% after 20 years
Radiation Associated with a mucinous histology and poor prognosis
Ureterosigmoidostomy 100–500 times increased risk at or adjacent to the
uretero-colonic anastomosis

7. Morphology
• CRCa may occur as a polypoid, ulcerating,
stenosing or infiltrative tumour mass.
• The majority (75%) lie on the left side of the colon
and rectum (rectum, 45%;descending/sigmoid;
30%; transverse; 5%; right-sided, 20%).
• 3-5% have a synchronous carcinoma at time of
diagnosis.

8. Clinical features
Rectal location
• PR bleeding: deep red on the surface of stools.
• Change in bowel habit: difficulty with
defecation, sensation of incomplete
evacuation, and painful defecation
(tenesmus).

9. Descending-sigmoid location
• PR bleeding: typically dark red, mixed with
stool, sometimes clotted.
• Change in bowel habit: typically increased
frequency, variable consistency, mucus PR,
bloating, and flatulence.

10. Right-sided location
• Iron deficiency anaemia may be the only
elective presentation.

11. Emergency presentations
• Up to 40% of colorectal carcinomas will present as
emergencies.
• Large bowel obstruction (colicky pain, bloating,
bowels not open).
• Perforation with peritonitis.
• Acute PR bleeding.

12. Diagnosis and investigations
Elective diagnosis
• by PR examination or rigid sigmoidoscopy for
rectal carcinoma.
• Flexible sigmoidoscopy should identify up to
75% of tumours (left-sided).
• Colonoscopy is generally a more reliable
investigation.

14. • Barium enema is appropriate if colonoscopy is
contraindicated or inappropriate.
• Tumour marker (CEA) can be used to monitor
disease if it is raised at diagnosis and falls to
normal after resection.

15. CEA
• A carcinoembryonic antigen (CEA) test is a
blood test used to help diagnose and manage
certain types of cancers, especially cancers of
the large intestine and rectum. This test can
also be used to help determine if a cancer
treatment is working.

16. A normal level of CEA is less than or equal to
3 nanograms per milliliter (ng/mL).
Increased levels of CEA may be found in the following
cancers:
• Colorectal or colon cancer
• Medullary thyroid carcinoma
• Breast cancer
• Cancer of the gastrointestinal tract
• Liver cancer
• Lung cancer
• Ovarian cancer
• Pancreatic cancer
• Prostate cancer

17. • The best use of CEA is as a tumor marker,
especially for cancers of the gastrointestinal tract.
When the CEA level is abnormally high before
surgery or other treatment, it is expected to fall
to normal following successful surgery to remove
all of the cancer. A rising CEA level indicates
progression or recurrence of the cancer. This
must be confirmed , as the CEA test by itself is
not specific enough to substantiate a recurrence
of a cancer. In addition, levels >20 ng/ml before
therapy may be associated with cancer which has
already spread (metastatic disease).

18. Emergency presentations
• Commonly diagnosed by abdominal CT scan.
• Single contrast enema may be used when the
diagnosis of large bowel obstruction is
possible and CT scanning is unavailable.
• Acute PR bleeding is sometimes investigated
by urgent colonoscopy.

19. Staging investigations
• Assessment of the presence of metastases (liver,
lung or para-aortic): commonest investigation is
thoracoabdominal CT scanning. CXR and liver
ultrasound is an alternative.
• Assessment of local extent. For colonic carcinoma
CT scanning is adequate. For rectal cancer pelvic
MRI and transrectal ultrasound are commonly used.
• Assessment of synchronous tumours. If not
diagnosed by colonoscopy or barium enema, one of
these is usually performed to identify synchronous
tumours.

20. Pathological staging
Duke's (approx. % 5y survival)
• A, confined to bowel wall only.
• B, through bowel wall.
• C, any with +ve lymph nodes.
• D, any with metastases.

21. Treatment
Potentially curative treatment
• Suitable for technically resectable tumours
with no evidence of metastases (or
metastases potentially curable by liver or lung
resection).
• Surgical resection (with lymphadenectomy) is
the only curative treatment.

22. • Typical operations:
– right/transverse: right/extended right
hemicolectomy;
– left: left hemicolectomy;
– sigmoid/upper rectum: high anterior resection;
– anorectal: abdomino-perineal resection (APER).
– lower rectum: low anterior resection/APER;

23. STANDARD RESECTIONS OF THE COLON

24. Left hemi-
colectomy

25. Right
hemi-
colectomy

26. Sigmoid
resection

27. Rectal
resection

28. Stapled
rectal
anastomosis
„doughnuts”

29. • Preoperative (neoadjuvant) chemoradiotherapy
may be used in rectal cancer to increase the
chance of curative resection.
• Adjuvant chemotherapy (5-FU based) is offered
for tumours with positive lymph nodes or
evidence of vascular invasion.
• Hepatic or lung resection may be offered to a few
patients with suitable metastases and a clear
resection of the primary tumour

30. Palliative treatment
For unresectable metastases or unresectable
tumours.
• Chemotherapy may effectively extend life
expectancy with a good quality of life.
• Obstructing tumours may be endoluminally stented
with self-expanding metal stents or transanally
ablated if rectal.
• Surgery reserved for untreatable obstruction,
bleeding, or severe symptoms.

31. LIVER METS.
• NEARLY 50% PTS PRESENTS WITH ISOLATED
LIVER METS AMENABLE TO SURGICAL
RESECTION IN THE FORM OF HEPATECTOMY.
1) WEDGE RESECTION.
2) ANATOMIC UNISEGMENTAL OR
POLYSEGMENTAL RESECTION.
3) LOBAR RESECTION.

32. NON RESECTIONAL SURGERY
• Hepatic Art. Infusion.
• Cryo-ablation.
• Radio Frequency Ablation (RFA).

33. PULONARY METS.
• ~2% of pts of lung mets are amenable to
metastectomy.

34. ISOLATED METS to other sites
• Oophorectomy for ovarian mets.
• Bone mets are treated with internal fixation &
irradiation.
• Brain mets are treated with Sx if possible,
or steroid & irradiation.

35. CHEMO THERAPEUTIC AGENTS
• 5 FU is the mainstay.
• IRINOTECAN & OXALIPLATIN has established
beneficial effect.

36. BIOLOGIC RESPONSE MODIFIERS
• BEVACIZUMAB is a monoclonal antibody
directed against vascular endothelial growth
factor.
• CETUXIMAB – AN ANTIBODY DIRECTED
AGAINST ENDOTHELIAL GROWTH FACTOR.

37. PALLIATIVE MEDICAL THERAPY
• Narcotic Agents.
• Antidepressants.
• Local Nv Block.
• Epidural Analgesic Pumps.

38. • 5-FU: steatosis
• Irinotecan: steatohepatitis
• Oxaliplatin: sinusoidal/vascular injury
• Bevacizumab
– Potential wound healing complications
– Need to wait 6-8 wks before surgical resection
• Cetuximab: no acute or chronic effects to date
Incidence of postoperative complications
increases with prolonged use

39. • Acneiform Eruption Associated With EGFR
Inhibitors