approach to colorectal cancer
TRANSCRIPT
Clinical Presentation
• Change in bowel habit– Loose stool– Frequent stool– Rectal bleeding– Tenesmus
• Rectal/abdominal mass
• Iron deficiency anaemia
• Screening
• Complications– Bowel Obstruction– Perforation
• Secondaries– Liver metastases – jaundice,
ascites, hepatomegaly
• General effects of cancer (likely metastases)– Anaemia– Anorexia– Weight loss
Right ColonAnaemiaMassPainUsually no change in bowel habitLess present with obstruction
Left ColonRectal BleedingChange in bowel habitMore present with obstruction
Rectal TumoursTenesmus‘Wet wind’Rectal Bleeding
Tumours disobey the rules, but generally…
Risk factors for Colorectal Cancer
• Increasing age• Colorectal polyps• Inflammatory bowel disease – UC• FHx
– FAP– HNPCC– Any first degree relative
• Obesity• Diet• Smoking• Acromegaly
Factors that may lower risk of Colorectal Cancer
• Diet rich in vegetables, garlic, milk, calcium• Exercise• Low dose aspirin & NSAIDS
Examination• General signs
– Anaemia– Evidence of weight loss
• Abdomen– Evidence of obstruction– Palpable mass
• Digital rectal examination– Rectal bleeding– Palpable mass in rectum/pouch of Douglas
• Evidence of spread– Hepatomegaly– Jaundice– Ascites– Supraclavicular lymphadenopathy
GP referrals for suspected LGI Cancer:
• When are you going to make an urgent referral?– Symptoms suggestive of LGI cancer– Age ≥40yrs with rectal bleeding + change in bowel
habit for ≥ 6 weeks– Age ≥60yrs with rectal bleeding without change in
bowel habit or anal symptoms for ≥ 6 weeks– Age ≥60yrs with change in bowel habit for ≥ 6 weeks– Any patient with RIF mass– Any patient with rectal mass– Iron deficiency anaemia <11 Males & <10 Females
• In borderline patients what important points in the history might sway you to refer urgently?– Particularly if Hx of Ulcerative Colitis or if FHx
• What test can the GP do that will be useful to the Colorectal specialist?– Full Blood Count
Investigations
• Gold standard =
• Visualise tumour• Take biopsies
• Alternatives:– Flexible sigmoidoscopy - & biopsies– Double contrast barium enema– CT colonography
COLONOSCOPY
Staging Investigations
• CT with contrast – Chest, Abdomen & Pelvis– Probably the only staging investigation required
• If another suspicious lesion found on CT, perhaps follow up with PET scan• Liver mets best investigated by MRI• If early rectal tumour (T1/T2) – endorectal USS (EUS)
Screening
• General population– Faecal occult blood test (FOB)– Age 60-73yrs– 6 test cards every 2 years for FOB– If FOB +ve…• →Colonoscopy
• High risk groups (strong FHx or UC)– Colonoscopy used for screening, not FOB
What is the role of serum CEA?
• Not for diagnosis of colorectal Ca• Not for screening• Useful for follow up – if CEA ↑ suggests
recurrence
How do we follow up patients post-colorectal cancer?
• Surveillance Colonoscopies
Dukes’ Classification
- A – Tumour confined to mucosa & submucosa- >90% 5 year survival
- B – Invasion of muscle wall- ~65% 5 year survival
- C – Regional Lymph Nodes involved- ~30% 5 year survival
- D – Distant spread e.g. liver, bladder
Spread of colorectal cancer• Local– Bladder & ureters– Small bowel &
stomach– Uterus/vagina or
prostate– Abdominal/Pelvic wall
• Lymphatics– Mesenteric LNs– Groin LNs (rectal CA)– Supraclavicular LNs
• Blood– Portal vein → Liver– Lungs
• Transcoelomic– Peritoneal seedings
Surgery for bowel cancer
• Principles:– Ideally empty bowel
• Enemas & laxatives
– Remove the tumour• Wide resection of growth
– Lymphadenectomy• Regional LNs
– Neo-adjuvant chemotherapy• Rectal Ca T1 or T2 only• Not colonic tumours• Aim to downsize tumour before surgery
Surgery for Colorectal Cancer
Ascending colon tumour → Right Hemicolectomy
Surgery for Colorectal Cancer
Transverse Colon Tumour → Transverse colectomy
Surgery for Colorectal Cancer
Descending colon tumour → Left Hemicolectomy
Surgery for Colorectal Cancer
Sigmoid Tumour → Sigmoid colectomy
Rectal Tumour → Abdominoperoneal (AP) resection
Surgery for Colorectal Cancer
Synchronous Colon Cancers
• 2 separate resections• Or subtotal colectomy:
Primary anastomosis
• Primary anastomosis– If minimal contamination– Healthy tissue quality – Clinically stable
Anastomotic breakdown/Anastomotic leak:
• High morbidity & mortality– Can be subtle or obvious– Fever– Oliguria– Ileus– Raised WCC & CRP– Peritonitis– Drain/wound – enteric contents– Usually non-specific examination unless peritonitic
• NEEDS URGENT CT ABDOMEN & PELVIS• Small abscess/localised collection – CT guided drainage with broad
spectrum antibiotics• IF GENERALISED PERITONITIS: NEEDS LAPAROTOMY
Stomas
• Temporary stoma– Primary resection with proximal diversion– To decompress dilated colon before resection of obstructing
lesion– Free perforation with peritonitis– Faecal contamination (unprepared bowel)– Poor nutrition – low albumin– For reversal procedure in future with anastomosis
• Permanent stoma– AP resections– Ileostomy after subtotal colectomy (although ileorectal
anastomosis is an option)
• A stoma is…– …surgically created communication between a
hollow viscus and the skin or external environment
– Ileostomies, Colostomies, Urostomies, technically a tracheostomy…
Colostomy
• Usually left-sided• Bag contains more solid stool• Flush to skin
Ileostomy
• Usually right-sided• Bag contains liquid stool• Spouted from skin– To protect against pancreatic enzyme secretions
Loop Ileostomy
• 2 openings when examine stoma• Ileum brought to surface & antimesenteric
boder opened• Rod is used to stop the opened bowel loop
falling back inside• Simple to reverse so used for temporary
diversion• Loop ileostomies preferable to loop colostomies
as better blood supply
Early complications of stomas• Bleeding
– unlikely to have large bleed– some blood in stoma bag
acceptable
• Ischaemia & necrosis– Dusky stoma colour– Needs resiting
• Retraction– Risk of faecal peritonitis– Back to theatre
• Obstruction– Due to oedema or hard stool– Examine stoma with gloves
• High output ileostomy– Severe dehydration– Electrolyte disturbances
• Parastomal dermatitis– Leaking ileostomy
Late complications of stomas
• Parastomal hernia– Stoma/bowel obstruction– Strangulation– Stoma may need resiting
• Prolapse• Stenosis of stomal orifice• Stomal diarrhoea• Psychological problems• Underlying disease e.g. Crohn’s peristomal fistulae
