General surgery (7) (GI cancers) Flashcards
colorectal cancer (bowel)
Common cancer- cancer of the colon or rectum. Small bowel and anal cancers less common
aetiology of bowel cancer
- Adenocarcinomas (rarer types inc lymphoma, carcinoid and sarcoma)
- Adenomas may be present for 10 years before becoming cancerous
bowel cancer DD
Differentials: IBD, haemarrhoids
risk factors for bowel cancer
- Family history of bowel cancer
- Familial adenomatous polyposis (FAP)
- Hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome
- Inflammatory bowel disease (Crohn’s or ulcerative colitis)
- Increased age
- Diet (high in red and processed meat and low in fibre)
- Obesity and sedentary lifestyle
- Smoking
- Alcohol
presentation of bowel cancer
- Change in bowel habit (usually to more loose and frequent stools)
- Unexplained weight loss
- Rectal bleeding
- Unexplained abdominal pain
- Iron deficiency anaemia (microcytic anaemia with low ferritin)
- Abdominal or rectal mass on examination
- Presenting with obstruction
- Tumour blocks passage through bowel- surgical emergency
- Right side colon cancer: abdominal pai, iron def anaemia, palpable mass in RIF or on PR exam
- Left side colon cancer: rectal bleeding, change in bowel habit, tenesmus, palpable mass in LIF
bowel cancer refferal
- Over 40 years with abdominal pain and unexplained weight loss
- Over 50 years with unexplained rectal bleeding
- Over 60 years with a change in bowel habit or iron deficiency anaemia
investigations for bowel cancer
- Bloods- FBC (microcytic – iron def anaemia), LFTs, clotting, carcinoembryonic antigen (CEA)- tumour marker
- Colonoscopy with biopsy- gold standard- biopsy if lesion found
- Sigmoidoscopy (if only features of rectal bleeding)
- CT colonography- pts less fit for colonoscopy- less detailed doesn’t allow for biopsy
-
Staging CT scan
- CT thorax, abdomen and pelvis (CT TAP)
Familial adenomatous polyposis (FAP)
- Autosomal dominant condition involving malfunctioning of the tumour suppressor genes called adenomatous polyposis coli (APC).
- It results in many polyps (adenomas) developing along the large intestine.
- These polyps have the potential to become cancerous (usually before the age of 40).
- Patients have their entire large intestine removed prophylactically to prevent the development of bowel cance (panproctocolectomy).
which gene is involved in FAP
malfunctioning of the tumour suppressor genes called adenomatous polyposis coli (APC).
Hereditary nonpolyposis colorectal cancer (HNPCC)
- Lynch syndrome.
- Autosomal dominant condition that results from mutations in DNA mismatch repair (MMR) genes.
- Patients are at a higher risk of a number of cancers, but particularly colorectal cancer.
- Unlikely FAP, it does not cause adenomas and tumours develop in isolation.
patients with FAP or HNPCC
These patients offered FIT screening at regular intervals
management of bowel cancer
Management
-
MDT approach
- Surgeons
- Oncologists
- Radiologists
- Histopathology
- Specialist nurse
-
Choice of managed depends on
- Clinical condition
- General health
- Stage
- Histology
- Patient wishes
- Options (in any combination)
- Surgical resection
- Chemotherapy
- Radiotherapy
- Palliative care
surgical resection for bowel cancer
Ideal to surgically remove entire tumour – potentially curative. Can also be used palliatively- reduce size of tumour and improve symptoms
- Laparoscopic surgery gives better recovery and few complications than open surgery
- Robotic surgery used increasingly
-
Surgery involves
- Identify tumour (may have been tattooed in endoscopy)
- Remove section of bowel containing tumour
- Creating an end-to- end anastomosis (sewing the remaining ends back together)
- Creating a stoma if end to end not possible
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complications of surgical resection for bowel cancer
There is a long list of potential complications of surgery for bowel cancer:
- Bleeding, infection and pain
- Damage to nerves, bladder, ureter or bowel
- Post-operative ileus
- Anaesthetic risks
- Laparoscopic surgery converted during the operation to open surgery (laparotomy)
- Leakage or failure of the anastomosis
- Requirement for a stoma
- Failure to remove the tumour
- Change in bowel habit
- Venous thromboembolism (DVT and PE)
- Incisional hernias
- Intra-abdominal adhesions
Faecal Immunochemical Test (FIT) and Bower Cancer Screening
-
Faecal immunochemical tests (FIT) look very specifically for the amount of human haemoglobin in the stool.
- FIT replaced the older stool test called the faecal occult blood(FOB) test, which detected blood in the stool but could give false positives by detecting blood in food (e.g., from red meats).
- Used for bowel cancer screening in UK
- Ages 60-74yo every 2 years
- If results positive à colonscopy
- FIT tests can be used as a test in general practice to help assess for bowel cancer in specific patients who do not meet the criteria for a two week wait referral, for example:
- Over 50 with unexplained weight loss and no other symptoms
- Under 60 with a change in bowel habit
classification of bowel cancer using
Dukes classification and TNM classification
Dukes’ Classification
Dukes’ classification is the system previously used for bowel cancer. It has now been replaced in clinical practice by the TNM classification, but you may come across it in older textbooks or question banks. A brief summary is:
- Dukes A – confined to mucosa and part of the muscle of the bowel wall
- Dukes B – extending through the muscle of the bowel wall
- Dukes C – lymph node involvement
- Dukes D – metastatic disease
TNM classification
T for Tumour:
- TX – unable to assess size
- T1 – submucosa involvement
- T2 – involvement of muscularis propria (muscle layer)
- T3 – involvement of the subserosa and serosa (outer layer), but not through the serosa
- T4 – spread through the serosa (4a) reaching other tissues or organs (4b)
N for Nodes:
- NX – unable to assess nodes
- N0 – no nodal spread
- N1 – spread to 1-3 nodes
- N2 – spread to more than 3 nodes
M for Metastasis:
- M0 – no metastasis
- M1 – metastasis
operations for colorectal cancer
- Right hemicolectomy involves removal of the caecum, ascending and proximal transverse colon.
- Left hemicolectomy involves removal of the distal transverse and descending colon.
- High anterior resection involves removing the sigmoid colon (may be called a sigmoid colectomy).
- Low anterior resection involves removing the sigmoid colon and upper rectum but sparing the lower rectum and anus.
- Abdomino-perineal resection (APR) involves removing the rectum and anus (plus or minus the sigmoid colon) and suturing over the anus. It leaves the patient with a permanent colostomy.
- Hartmann’s procedure is usually an emergency procedure that involves the removal of the rectosigmoid colon and creation of an colostomy. The rectal stump is sutured closed. The colostomy may be permanent or reversed at a later date. Common indications are acute obstruction by a tumour, or significant diverticular disease.
Low Anterior Resection Syndrome
Low anterior resection syndrome may occur after resection of a portion of bowel from the rectum, with anastomosis between the colon and rectum. It can result in a number of symptoms, including:
- Urgency and frequency of bowel movements
- Faecal incontinence
- Difficulty controlling flatulence
follow up after bowel cancer resection
Follow-Up
Patients will be followed up for a period of time (e.g., 3 years) following curative surgery. This includes:
- Serum carcinoembryonic antigen (CEA)
- CT thorax, abdomen and pelvis
stomach cancer
Majority of gastric cancers arise from gastric mucosa as adenocarcinomas. The rest are a mixture of connective tissue, lymphoid or neuroendocrine malignancies
DD for stomach cancer
- Peptic ulcer disease
- GORD
- Gallstone
- Pancreatic cancer
RF for gastric cancer
(rate has improved in the west due to H.pylori eradication therapy and improved diet)
- H.pylori
- Male
- Age
- Smoking
- Alcohol
- Positive family history
- Pernicious anaemia
presentation of gastric cancer
- Vague and non-specific – pts present at advanced stage
- Dyspepsia
- Dysphagia
- Early satiety
- Vomiting (haematemesis
- Melaena
- Non-specific cancer SYMPTOMS
- ANOREXIA
- WEIGHT LOSS
- ANAEMIA
- Clinical signs usually absent
- Epigastric mass in late disease
- Troisiers sign- palpable left supraclavicular node (Virchow node)- metastatic abdominal malignancy
- Metastatic signs
- Hepatomegaly
- Ascites
- Jaundice
- Acanthosis nigricans (hyper pigmentation of skin creases e.g. axilla
Troisiers sign
- palpable left supraclavicular node (Virchow node)- metastatic abdominal malignancy
investigations for gastric cancer
- Bloods: FBC, LFT
- Imaging
- Urgent upper GI endoscopy (OGD)- any patients presenting with new-onset dysphagia or aged >55 years presenting with weight loss and either upper abdominal pain, reflux, or dyspepsia.- signet ring cells
- Biopsy
- Histology- neoplasia
- CLO test- H.pylori
- HER2/neu protein expression (targeted monoclonal therapies)
- Staging- CT chest-abdomen-pelvis and staging laparoscopy (looking for peritoneal metastases)- TNM staging
which cells may be found in a biopsy after OGD in gastric cancer
signet ring cells
Helicobacter Pylori
- The most important modifiable risk factor identified in developing gastric cancer is infection of the stomach mucosa by Helicobacter Pylori.
- H. Pylori is a Gram negative helical bacterium that produces the urease enzyme, acting to break down urea into CO2 and ammonia.
- The ammonia neutralises stomach acid, allowing the bacterium to create an alkaline microenvironment.
- It subsequently sets off a cycle of repeated damage to the epithelial cells, leading to inflammation, ulceration, and ultimately gastric neoplasia.
Helicobacter Pylori eradication therapy
- (x7-14 days)
- PPI
- X2 antibiotics
- Amoxicillin
- Metronidazole
management of gastric cancer
- MDT approach
- Adequate nutrition
- NG, RIG may be needed
- Curative treatment- surgery
- Peri-operative chemotherapy
- 3 cycles neoadjuvant and 3 cycles adjuvant
- Surgery
- Peri-operative chemotherapy
- Palliative care
gastrectomy
The aim of surgery is to achieve loco-regional control by removing the tumour and its local lymph nodes. The type of operation performed depends on the region of the malignancy:
- Proximal gastric cancers – total gastrectomy
- Distal gastric cancers (antrum or pylorus) – subtotal gastrectomy
reconstruction after gastrectomy
The most commonly used method in reconstructing the alimentary anatomy is the Roux-en-Y reconstruction as it gives the best functional result, in particular with less bile reflux.
Post-gastrectomy, distal oesophagus is end-to-end anastomosed directly to the small bowel, and the proximal small bowel is end-to-side anastomosed also to the small bowel
endoscope mucosal resection (EMR) and gastric cancer
Patients with early T1a tumours (tumours confined to the muscularis mucosa) may be offered an Endoscopic Mucosal Resection (EMR). This has the advantage of a greatly reduced morbidity, mortality, and quality of life impact, however is only used in early tumours therefore current use in clinical practice is rare.
presentation of liver cancer
- Liver cirrhosis
- Fatigue
- Fever
- Weight loss
- Lethargy
- Dull ache in right upper quadrant
- Ascites
- Jaundice
- One examination
- Irregular enlarged, craggy and tender liver
secondary liver malignancy investigations
- Similar to HCC
- Bloods
- Derangement of LFTS (ALPs most raised)
- Imaging
- US imaging of choice
- Staging
- CT
- Biopsy not advice if tumour is operable- needle tract may lead to seeding of tumour
