Colorectal Cancer

M. N. Jalalian

Medical Intern

Tehran University of Medical Sciences

Most common malignancy of GI

Aging Dominant

after age 50

Hereditary Risk Factors 20% with a family history

FAP, HNPCC

Environmental and Dietary Factors Saturated or polyunsaturated fats

Inflammatory Bowel Disease long-standing colitis

Other Risk Factors Cigarette smoking, Ureterosigmoidostomy, Acromegaly,

Pelvic irradiation

Epidemiology and Risk Factors

Familial Adenomatous Polyposis

Attenuated FAP

Hereditary Nonpolyposis Colon Cancer (Lynch Syndrome)

Familial Colorectal Cancer

Inherited Colorectal Carcinoma

Definition:

An autosomal dominant condition with numerous polyps and increased risk of colorectal cancer

A known family history of FAP with even one adenomatous polyp …or

Developing hundreds to thousands of adenomatous polyps shortly after puberty (without a family history)

Familial Adenomatous Polyposis

1% of all colorectal adenocarcinomas

mutation in the APC gene (5q)

75% of cases

25% without a family history

Lifetime risk of colorectal cancer 100% by age 50 years

Treatment is surgical

Most patients elect to have an ileal pouch–anal anastomosis

FAP

fewer polyps (usually 10 to 100)

The right colon

Cancer risk 50%

APC mutation testing + in 60%

Screening by colonoscopy

Unknown family mutation

at age 13–15y, then every 4y to age 28y.

Treatment is surgical

Total abdominal colectomy with ileorectal anastomosis

Attenuated FAP

Definition:

An AD genetic condition

High risk of colorectal carcinoma at an early age (average age: 40–45 years) & other cancers

More common than FAP

70% develop cancer

HNPCC (Lynch Syndrome)

Is based on family history

The Amsterdam criteria:

3 affected relatives (one must be a first-degree relative of one of the others)

in 2 successive generations of a family

one patient diagnosed before age 50 years.

HNPCCDiagnosis

Screening

Colonoscopy

annually

At age 20–25y / 10y younger than the youngest age at diagnosis in the family.

Transvaginal ultrasound / Endometrial aspiration biopsy

Annually

age 25–35y

HNPCCCntd...

Total colectomy with ileorectal anastomosis

once adenomas or a colon carcinoma is diagnosed

prophylactic colectomy

prophylactic hysterectomy

bilateral salpingo-oophorectomy

women who have completed childbearing

HNPCCTreatment

10–15% of colorectal cancer

Risk of cancer increases with a family history.

Double with one first degree relative (12%)

35% with 2 first degree relatives

Screening Colonoscopy

every 5 y

at age 40y / 10y before the age of the earliest

Familial Colorectal Cancer

Nonspecific

a change in bowel habits

rectal bleeding

Abdominal pain

Bloating

Obstruction is more likely in Left-sided tumors

unexplained anemia

weight loss

Clinical Presentation

Tumor stage (T) Definition

T0 No evidence of cancer

Tis Carcinoma in situ

T1 Tumor invades submucosa

T2 Tumor invades muscularis propria

T3 Tumor invades through muscularispropria into subserosa or into nonperitonealized pericolic or perirectal tissues

T4 Tumor directly invades other organs or tissues or perforates the visceral peritoneum of specimen

Staging

Nodal stage (N) Definition

NX Regional lymph nodes cannot be assessed

N0 No lymph node metastasis

N1 Metastasis to one to three pericolic or perirectal lymph nodes

N2 Metastasis to four or more pericolic or perirectal lymph nodes

N3 Metastasis to any lymph node along a major named vascular trunk

Staging

Distant metastasis (M)

MX Presence of distant metastasis cannot be assessed

M0 No distant metastasis

M1 Distant metastasis present

Staging & 5-year suvival

Stage TNM 5-Year Survival

I T1–2, N0, M0 70–95%

II T3–4, N0, M0 54–65%

III Tany, N1-3, M0 39–60%

IV Tany, Nany, M1 0–16%

Colonoscopy

Synchronous disease up to 5%

Chest and Abdominal/pelvic CT scan

distant metastases

Routine Blood tests and CEA

Endorectal ultrasound / Pelvic MRI

The ultrasound T and N stage of rectal cancer

Preoperative Evaluation

The objective is

remove the primary tumor with clean borders

And its lymphovascular supply

Chemotherapy

Stages III and IV

Stage II if

Young patient

Bad histology

Radiotherapy

Greatly used for rectal cancers

Treatment

Stage 0 (Tis, N0, M0)

Polipectomy with clean margins

Stage I: The malignant polyp (T1, N0, M0)

Polipectomy by endoscope (low risk of LN metastasis)

Segmental colectomy

Stages I and II: Localized colon carcinoma (T1–3, N0, M0)

The majority cured with surgical resection

Adjuvant chemotherapy

young patients

“high-risk” histologic

THERAPY FOR COLONIC CARCINOMA

Stage III: Lymph Node Metastasis (T any, N1, M0)

Surgery

adjuvant chemotherapy

Stage IV: Distant metastasis (T any, N any, M1)

metastases limited to the liver

Resection

adjuvant chemotherapy

The remainder

Palliative therapy

Stage I: Localized rectal carcinoma (T1–2, N0, M0) Polypectomy

low risk of metastasis

Radical resection High-risk patients

Stage II: Localized rectal carcinoma (T3–4, N0, M0) total mesorectal resection (only)

Resection and chemoradiation neoadjuvant therapy

Adjuvant therapy

Therapy for Rectal Carcinoma

Stage III: Lymph node metastasis (T any, N1, M0)

Resection

neoadjuvant chemoradiation

Adjuvant chemoradiation

Stage IV: Distant metastasis (T any, N any, M1)

Mostly palliative

A full colonoscopy

within 12 months

If normal, every 3-5y

CEA

every 2–3 months for 2 years

If + CT scan

Transrectal sonography

Rectal Cancer

Every 4 months for 4 y

Follow-Up and Surveillance

THANK YOU FOR YOUR ATTENTION