Download Colorectal Cancer

Prof Clement F. Kiire
MBChB, MMed, MRCP(UK), FRCP(London),
FRCP(Glasgow), FRCP(Edinburgh), FCP(SA),
FESG, MD(Makerere)
 Describe
cancer
the significance of colon
 Identify
the factors and conditions
associated with colon cancer
 Describe
the treatment options
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90% of cases occur after age 50
Third leading cause of cancer in the US
Second leading cause of cancer death
Average lifetime risk for developing this
cancer is 6%
Men and women are affected equally
Women are more likely to have right sided
colonic adenomas
Distributed evenly among racial groups
Africans and Hispanics have a lower survival
rate
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Age >50 yrs
High fat, low fiber diet
IBD – Chronic ulcerative colitis and Crohn’s disease
Familial adenomatous polyposis (FAP)
Hereditary nonpolyposis colorectal cancer (HNPCC)
Hamartomatous polyposis syndromes
Peutz-Jegher’s syndrome
Juvenile polyposis
Family history – colorectal adenomas, colorectal cancer
Personal history of colorectal adenomas;
ureterosigmoidostomy; breast, ovarian and uterine
cancers
Factors associated
with increased risk of
CRC
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Lack of physical
activity
Consumption of red
meat
Obesity
Cigarette smoking
Alcohol use
Factors associated
with decreased risk
of CRC
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Foods containing
folic acid
ASA and other
NSAIDs
Postmenopausal HRT
Ca supplementation
Selenium
Consumption of
fruits, vegetables
and fiber
Depends on tumour location:
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Proximal (right-sided) lesions present
with symptoms caused by anaemia:
fatigue, weight loss, shortness of
breath, lightheadedness, mahogany
faeces caused by occult bleeding
Distal (left-sided) lesions present with
symptoms of obstruction: changes in
BM pattern, post-prandial colicky
abdominal pain, fresh rectal bleeding.
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Abdominal pain - 44%
Change in bowel habit - 43%
Fresh rectal bleeding or melaena - 40%
Weakness - 20%
Anaemia without other gastrointestinal
symptoms - 11%
Weight loss - 6%
Some patients have more than one
abnormality
15-20% of patients have distant
metastatic disease at the time of
presentation
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Digital rectal exam (DRE)
Barium enema (BE) with or without air
contrast
Sigmoidoscopy, rigid type or flexible fiber
optic type
Colonoscopy (or colon endoscopy)
Computed tomography (CT)
Transrectal ultrasound (TRUS)
Magnetic resonance imaging (MRI)
Laparotomy
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Digital rectal exam (DRE)
Barium enema (BE) with or without air contrast:
used primarily to locate deformities of intestinal
topography
Sigmoidoscopy, rigid type or flexible fiber optic
type: used to visualize local rectal tumors or for
routine screening
Colonoscopy (or colon endoscopy): Direct visual
examination of the colon and rectum detects early
polypoid tumors preoperatively and recurrences
post-resection; Multiple biopsies may be
performed at time of study to increase sensitivity.
DIAGNOSTIC TEST CONT’D
•Computed tomography (CT): Used to stage
disease and identify metastases
•Transrectal ultrasound (TRUS): An
excellent choice for preoperative staging of
rectal carcinomas
•Magnetic resonance imaging (MRI): very
useful for diagnosing metastatic disease
•Laparoscopy: Useful in detecting
metastases to abdominal regions (especially
omentum or liver) that often remain
undetected by current imaging techniques
Carcinoembryonic antigen (CEA)
Carbohydrate antigen (CA) 19 9, CA 50, and CA 195
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have a low diagnostic ability to detect primary
CRC
overlap with benign disease
low sensitivity for early stage disease
have prognostic utility
An expert panel on tumour markers convened by
the American Society of Clinical Oncology (ASCO)
recommended that serum CEA levels not be used
as a screening test for colorectal cancer
Primary tumour (T)
 TX - Primary tumour cannot be assessed
 T0 - No evidence of primary tumour
 Tis - Carcinoma in situ: intraepithelial or
invasion of lamina propria
 T1 - Tumour invades submucosa
 T2 - Tumour invades muscularis propria
 T3 - Tumour invades through the muscularis
propria into the subserosa or into
nonperitonealized pericolic or perirectal
tissues
 T4 - Tumour directly invades other organs or
structures, and/or perforates visceral
peritoneum
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Regional lymph nodes (N)
NX - Regional lymph nodes cannot be
assessed
N0 - No regional lymph-node metastasis
N1 - Metastasis in 1 to 3 regional lymph
nodes
N2 - Metastasis in 4 or more regional lymph
nodes
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Distant metastasis (M)
MX - Distant metastasis cannot be assessed
M0 - No distant metastasis
M1 - Distant metastasis
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Stage
Stage
Stage
Stage
Stage
Stage
Stage
I (T1-2N0) - 93%
IIA (T3N0) - 85%
IIB (T4N0) - 72%
IIIA (T1-2 N1) - 83%
IIIB (T3-4 N1) - 64%
IIIC (N2) - 44%
IV - 8%
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Faecal occult blood test (FOBT) every year
◦ Occult stool testing must be repeated at least 3
times on different stool samples.
◦ Diet must be free of peroxidase activity (turnips
& horseradish).
◦ Tests may need to be repeated if there is a
history of:
 usage of possible gastric irritants such as salicylates,
other anti-inflammatory agents
 haemorrhoids
 diverticulitis
 peptic ulcer disease (PUD) or other cause of GI
bleeding
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Symptoms require diagnostic work up
Offer screening to men and women aged 50 and older
Stratify patients by risk
Options should be offered
Follow up of positive screening test with diagnostic
colonoscopy
Appropriate and timely surgery for detected cancers
Follow up surveillance required after polypectomy and
surgery
Providers need to be proficient
Encourage participation of patients
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Complete blood count (CBC)
Liver chemistries
Carcinoembryonic antigen level (CEA)
C-Reactive protein (CRP)
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Complete blood count (CBC)
Anemia may be a symptom of right-sided
bowel cancer
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Liver chemistries:
Abnormal liver enzyme results may suggest
metastatic disease
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Carcinoembryonic antigen level (CEA):
◦ Normal value: 0-2.5 mg/ml; up to 10 mg/ml in
tobacco smokers
◦ Useful in establishing diagnosis and recurrence for
tumours that secrete CEA and in following disease
progression
◦ Because colon lesions are not likely to secrete CEA, it
is not a highly reliable indicator of colon cancer
◦ If CEA is elevated, return to normal levels is expected
to occur within 48 hours after complete tumour
excision
 C-Reactive
protein (CRP):
◦ Increased plasma concentration of
CRP is associated with subsequent
development of colon cancer
◦ Preliminary findings are consistent
with the established association
between colon cancer and
inflammatory bowel disease (IBD)
◦ CRP research is ongoing and full
corroboration of suggestive findings
has not been established
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Genotyping (APC gene test) should be used
when other diagnostic avenues have been
exhausted
Medically necessary in presence of strong
family history for familial adenomatous
polyposis (FAP), attenuated familial
adenomatous polyposis (AFAP), or hereditary
non-polyposis colorectal cancer (HNPCC)
Benign lesions
Crohn’s colitis
Diverticulosis
Endometriosis
Solitary rectal ulcer
Lipoma
Tuberculosis
Amoebiasis
Cytomegalovirus
Fungal infection
Extrinsic lesion
Arterio-venous malformations
Adenomatous polyps◦ Premalignant neoplasm
◦ Morphological typestubular, tubulovillous,
villous
Ischemic colitis
Infarcted colon
Megacolon
Haemorrhoids
Malignant lesions
Adenocarcinoma
Lymphoma
Carcinoid tumor
Kaposi’s sarcoma
Prostate cancer
Surgical excision: mainstay of curative Rx
 Specific procedure depends on the
anatomic location of the cancer, but
typically involves hemi-colectomy
 Surgical resection of affected bowel with
clear margins, along with the adjacent
mesentery and at least 12 regional nodes
 For rectal tumours, total meso-rectal
excision with a distal surgical margin of at
least 2cm is recommended
 For tumours that are located within 6cm of
the anal verge, or involve the anal
sphincter, wide surgical resection with
abdomino-perineal resection and
permanent colostomy is recommended
 Local excision, for palliative treatment or
Radiation therapy:
 Postoperative radiation, with or without
chemotherapy, significantly reduces local
recurrence rates
 Common regimen incorporates infusional 5fluorouracil (5-FU) as a radiosensitizer to
boost the efficacy of pelvic radiation
 Administered as 45-55 Gy over 5 weeks
 Repeated as needed
Systemic chemotherapy
 5-FU has been the mainstay of systemic
chemotherapy for CRC
 Capecitabine was approved in 2001 as firstline therapy for metastatic CRC
 Irinotecan (Camptosar), Oxaliplatin (Eloxatin),
Bevacizumab, Cetuximab
Electrocoagulation
 Mostly palliative treatment for rectal
carcinomas
 Curative for small subset of patients
Palliative Care
• For advanced incurable cancers
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Colorectal Cancer is one of the leading Cancers
in the world.
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It is a major cause of morbidity and mortality.
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It is caused by a combination of environmental
lifestyle issues and genetic causes.
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Increasing Cancer rates in developing Countries
including Uganda.
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Need for a national Cancer plan for all Cancers
including Colorectal Cancer.