Bowel Cancer

<Presentations>

<Index>

 

 

Type

- Adenocarcinoma vast majority

- SCC from anal verge

- Cloacogenic carcinoma from direct invasion

 

Causes

- Familial Adenomatous Polyposis (FAP)

- Hereditary Non-Polyposis Colon Cancer (HNPCC)

 

Categories of Risk

- 1: RR <2

- 2: RR 3-6

-  2% population

-  1st degree relative< 55 yrs Dx or

-  2 1st/2nd degree relatives (same side)

- 3: RR = 50% chance

-  < 1% population

-  3 1st/2nd degree relatives (same side) or

-  Multiple Ca

 

Features

- Peak age 50-70 yrs

- Australias 2nd most common cancer in men & women, most common when taken together

- 2nd most common cause of Ca death

- Left sided colon Ca worse prognosis but detected earlier

- Right sided colon Ca better prognosis but presents late

 

Screening

- Screen everyone 50+

-  Uncommon < 45

- 40% decrease in mortality

- Find

-  90% bowel Ca

-  60-75% large adenomas (polyps)

- FOBT

- Sigmoidoscopy, Colonoscopy

- +/- barium enema

 

Associated S/S

- Polyps

- IBD > 8 years

- Haematochezia: rectal

-  Anaemia

- Change in bowel habit

- Abdominal pain

- Weight loss, anorexia

- Abdominal/rectal mass

- Hepatomegaly

- Bowel obstruction

 

Ix

- Digital Recatal Examination (DRE)

- Cancer Markers

-  Cancer Antigen 19-9 (CA19-9)

-  Carcino-Embryonic Antigen (CEA)

- FOBT

- FBE: anaemia (IDA)

- U&E, LFT

- AXR: apple core

 

Bowel Ca

 

Dukes Staging

- A: mucosal or submucosal only, carcinoma in situ

- B: into muscularis or into serosa

- C: regional lymph nodes

- D: metastasis to liver, bones..

 

Complications

- Metastasis

-  To colon: stomach, breast, pancreas, ovary

-  From colon: liver (25%), retroperitoneal (15%), kidney (13%), adrenal (10%)

- Obstruction

- Perforation

- Intussusception

- Pneumatosis intestinalis

 

Mx

- Family/genetic counseling

- Surgical resection: colectomy

- Multiagent chemotherapy