Colorectal Cancer…

Presented by:

Anas jolani – amiral aiman –ahmed fathi

Epidemiology ..• It is a disease with a known geographical variation.

• Incidence varies from 4/100,000 to 40/100,000.

• Mean age in the west is 63. Here in Jordan, it is 61.

• In Jordan, 13% of cases are below 45 years, while 6% in the west.

• Nearly equal incidence in both sexes. Some statistics show slight male predominance.

• #1 cancer in males. #2 cancer in females (after breast).

Age

Ulcerative colitis

Polyps

Hereditary

conditionsFamily history

Risk Factors

FAP

HNPCC

10 years, involving the whole colon

Low fiber diet,

refined carbs, high animal fat

Alcohol &

smoking

Screening at age of 50

Polyps [Adenoma]

Descriptive term for any elevation in the mucosa.

>95% of colon cancer occur

on top of polyps.

>> Adenomatous

polyps are PRE-

MALIGNANT!

Described grossly:

-Sessile-Pedunculated

Described pathologically:

-Tubular-Villous-Tubulovillous

Clinical presentation:

-Mostly incidental

-Rectal bleeding

-Change in bowel habit

-Pain, N&V > obstruction

Tubular adenoma

-more common than villous-usually pedunculated

-less common than tubular-usually sessile -appear as velvety or cauliflower-like projections-maybe up to 10 cm in diameter-much more likely to harbour invasive carcinoma (about 40%)

Villous adenoma

Factors that increase the risk of transformation into malignancy:

1- Size

2- Histology

3- Dysplasia

Villous

*Why do they become malignant?

Mutations (inherited, environmental)>Inactivation of suppressor gene: APC, mismatch repair

>Activation of oncogene: K-ras

*Management: polypectomy by endoscopy or surgically if too large.

Familial Adenomatous Polyposis

-Autosomal dominant

-Clinically defined by the presence of more than 100 colorectal adenomas

-Accounts for less than 1% of colorectal cancer

-Risk of colorectal cancer is 100%!

*80% with +ve family history. 20% arise from new mutations in APC gene.

Patients start to develop polyps early in teenage.By the 4th decade, ALL patients have colorectal cancer!

Management:

In the past: Colectomy with ileorectal anastomosis

>carries risk of cancer in the rectum

Now: Restorative proctocolectomy with ileoanal anastomosis

Hereditary NonPolyposis Colorectal Cancer (HNPCC)

-Lynch syndrome-Autosomal dominant-Mean age of diagnosis is 44 years-5-6% of colorectal cancer-Lifetime risk of colorectal cancer is 80%-Caused by mutation in one of the DNA mismatch repair genes

-Most cancers develop in the proximal colon-High incidence of synchronous & metachronous tumors (colon, endometrium, ovary, stomach)

HNPCC can be diagnosed by genetic testing, or Amsterdam criteria II:

-Three or more family members with an HNPCC-related cancer, one of whom is a first-degree relative of the other two.

-Two successive affected generations.

-One or more of the HNPCC-related cancers diagnosed before the age of 50 years. -Exclusion of FAP.

Colon CancerThe most common GI cancer

>98% is Adenocarcinoma

2%: carcinoid, leiomyosarcoma, lymphoma …

Grossly:

Fungating lesion

Ulcerating lesion

Stenosing lesion: left colon > intestinal obstruction

Mass lesion: cecum & ascending colon

Fungating, mass lesion Stenosing lesion

Mass lesion with ulceration

A gradual shift toward right-sided or proximal colon cancers has been observed both in the United States and internationally

Symptoms Asymptomatic: discovered by screening

Change in bowel habit ( constipation, diarrhea, alteration )

Rectal bleeding ( any type : fresh , altered, drops, clots, black )

Abdominal discomfort, weight loss and tiredness (anemia) { more with Rt. colon CA }

20% of cases present as Emergency: intestinal obstruction, peritonitis due to perforation, massive bleeding

*Any colonic bleeding >40 years require complete investigation of the colon.

Signs

Pallor.

Abdominal mass.

PR mass.

Jaundice.

Nodular liver

Ascitis.

Investigations

•Confirm diagnosis.

•Evaluation of the whole colon.

•Evaluation of the extent of the disease.

Investigationso CBC, LFT

o Fecal occult Blood test.

o Barium enema.

oCT colongraphy (virtual colonography)

o Lower Endoscopy/ colonoscopy/ sigmoidoscopy

oEndorectal US for rectal Ca

oCEA Tumor marker. “Follow up & recurrence”

oCT, MRI, Chest X-ray, PET scan “metastasis”

Fecal occult blood testWe look for occult blood in the stool.

The advantages of this test are that it is simple and not expensive.

Both the sensitivity and specificity of this test are low.

Other diseases produce blood like hemorrhoids, anal fissures and peptic ulcers.

Therefore this test is not a diagnostic test.

Lower Endoscopy

The lower endoscopy includes both colonoscopy and sigmoidoscopy.

It can be both diagnostic and therapeutic since the doctor can remove a polyp if he finds one.

colonoscpy is the investigation of choice for colorectal cancer

Barium Enema

•The barium blocks X-rays, causing the barium-filled colon to show up clearly on the X-ray picture.

•We look for filling defects in the presence of colorectal cancer.

•Characteristic apple core appearance

Staging

- TNM

- Dukes’

- modified Dukes

TNM staging

T : tumor

N : lymph nodes involved

M : metastasis

Dukes’ classification

A: tumor within the wall.

B: tumor through the whole wall.

C: involvement of lymph nodes (C1,C2)

D: metastatic spread.

Mode of spread

Direct spread to adjacent structures (may cause fistula)

Lymphatic.

Vascular (commonest sites: liver, lung, bone, brain)

Transcoelomic (shedding into peritoneal cavity leading to ascites)

Treatment

*** The treatment is individualized..

SurgeryChemotherapy (systemic, chemoembolization) (before (neoadjuvant) or after (adjuvant) surgeryRadiotherapy (external, internal) (before or after surgery)Combination chemotherapy and radiotherapy

Surgery

The primary treatment.Curative or palliative.Resection & re- anastomosis as one stage.Stoma

Types of surgeriesRight hemicolectomy

Left hemicolectomy

Total colectomy

sigmoidectomy

Anterior resection ( removal of the rectum )

Abdominoperineal resection (removal of the rectum and the anal canal )

Put colostomy (permanent or temporary )

Put ileostomy

Put any other stomy

Right Hemicolectomy and ileocolic anastomosisfor Cecal / Right Colon Cancer

Left Hemicolectomy and anastomosis of colon and rectum for Left Colon Cancer

Sigmoid Colectomy and anastomosis of colon and rectum for Sigmoid Cancer

Total colectomy needs to be considered for multiple tumors

Prognostic factors

Stage ( most important factor )Pathology (differentiation, vascular & peri-neural invasion)DNA content ( aneuploidy or diploidy )Mucin secreting tumour or notTechnique and surgeon experiencePerforation.Co-morbidity and general condition of the patient

Prognosis

5-year survival rate:Stage I: 90%.Stage II: 60-80%.Stage III: 20-50%.Stage IV: < 5%.

Rectal tumors

- Symptoms mainly:Hematochezia (fresh blood), mucus with stool, tenesmus and feeling of incomplete evacuation, Alteration in bowel habit : Early morning diarrhoea. Urinary symptoms

- Signs:by PR examination >> mass, can give information on the size, fixation, ulceration, local invasion, and lymph node status

Types of carcinoma spread

1- Local spread: Local spread occurs circumferentially rather than in a longitudinal

direction. If penetration occurs anteriorly, the prostate, seminal vesicles or bladder

become involved in the male; in the female, the vagina or the uterus is invaded. In either sex, if the penetration is lateral, a ureter may become involved, while posterior penetration may reach the sacrum and the sacral plexus.

2- Venous spread, liver, lungs, adrenals.

3-Lymphatic spread.

4-Peritoneal dissemination

Staging

Dukes classified carcinoma of the rectum into stages :A : The growth is limited to the rectal wall (15%): prognosis excellent.

B : The growth is extended to the extrarectal tissues, but no metastasis to the regional lymph nodes (35%): prognosis reasonable.

C : There are secondary deposits in the regional lymph nodes (50%). These are subdivided into C1, in which the local pararectal lymph nodes alone are involved, and C2, in which the nodes accompanying the supplying blood vessels are implicated up to the point of division : prognosis is poor.

D : stage D is often included, which was not described by Dukes. This stage signifies the presence of widespread metastases, usually hepatic.

Investigations

Rigid or flexible sigmoidoscopy.

Biopsy : Using biopsy forceps via a sigmoidoscope, a portion of the edge of the tumor can be removed. If possible, another specimen from the more central part of the growth should also be obtained.

Barium Enema

Trans-rectal ultrasonography has an accuracy of approximately 75% for T stage and 65% for N stage; it should be an integral part of the staging of rectal tumors.

Endorectal US

• It shows us the layers of the rectal wall and to see the depth of invasion through mucosa

• it can help to reach the diagnosis

Surgical Treatment

goals: to remove cancer with adequate margins and perform an anastomosis only if there’s:

1- good blood supply,

2- absence of tension, and

3- normal anal sphincters.

*** If any of these conditions cannot be met, the entire rectum must be removed and the patient left with a permanent colostomy.

Colostomy

Surgical option depends on:

• The height of the lesion,

• The condition of the sphincters,

• The condition of the patient.

Options we have:

• Low anterior resection: is the operation of choice for tumors that can be resected with an adequate distal margin

• Abdominoperineal resection:is performed for tumors that cannot be resected with a 2-cm distal margin or if sphincter function is questionable.

• Colonic J-pouch or coloplasty:may also be constructed to recreate the reservoir function of the rectum

Anterior resection and anastomosis of colon and rectum for upper and middle rectal tumors

Abdominoperineal resection – resection of anus rectum and part of segmoid colon and leave a permanent colostomy for lower

rectal tumors

Adjuvant therapy

• for rectal cancer should routinely be considered to reduce local recurrence and possibly improve overall survival.

• Preoperative radiotherapy • Neoadjuvant chemoradiation, including

chemotherapy with a 5-fluorouracil–based regimen.

THE END! :)