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Lower GI Cancers

Colorectal cancer ( CRC ) or Bowel cancer – cancer arising from the epithelium of the colon or rectum

Third most common cancer in men and 2nd most common in women worldwide Slightly ↑ common in men Incidence ↑ es with age ( except familial colorectal cancer ) Incidence increasing worldwide and mortality decreasing Almost always adenocarcinoma

 Family history
○ strong family history of CRC and or polyps
○ early age at diagnosis of CRC
○ Inherited conditions as Famililal adenomatous polyposis
 Lynch syndrom ( Heridetary non polyposis colon cancer HNPCC) most common cause of heridetary bowel cancer
☼ All patients with colorectal cancer should be tested for Lynch syndrome – NICE advice BMJ 2017;356:j998

○ BRCA1 gene mutation →possibly ↑ risk in women under 50 of CRC
 Benign polyps in bowel
○ most bowel cancers develop from an adenoma
○ slow growing 
 Ulcerative colitis and Crohn’s disease
○ risk ↑ by 70 %
 Previous h/o CRC or h/o other cancers as
○ lymphoma
○ oesophageal cancer
○ renal or bladder cancer
○ breast cancer
○ uterine or cervical cancer
○ head and neck cancer
○ prostate cancer
 Radiation exposure eg
○ previous radiotherapy treatment
○ diagnostic background radiation
 Other comorbid conditions as
○ diabetes
○ gallstones
○ acromegaly
 Smoking tobacco
○ risk ↑es with number of ciggarettes smoked/ day
○ risk 33 % higher compared to people with normal BMI
○ link with eating too much red and processed meat
○ high fat and low fiber diet
 Lack of physical activity
○ particulary in men

Screening identifies a few patients , remainder present with symptoms , with around a quarter presenting as an emergency
 Half of patients do not meet the NICE USC guidance and have longer diagnostic interval
 Mortality from CRC is strongly related to the 1st symptom with mildly anaemic patients having the worst prognosis
 Diagnostic delays – anaemia , rectal bleeding and abdominal pain are the most usual missed oppurtunities

○ patient with mild anaemia can still have colorectal cancer even if Hb is above the threshold recommended by NICE for urgent investigations
○ people over 60 → ♂ with Hb <= 120 and ♀ Hb <= 110 → worth investigating for cancer
○ Irritable bowel syndrome in people over 50 r/o other diagnosis like CRC/ ovarian cancer and monitor response to treatment
Bowel sympton checker for public and primary care- see screenshot 

More than 2300 new diagnoses of CRC annually in UK in patients aged less than 50 – incidence of CRC and IBD are ↑ ing in those < 50 yrs
 These patients ( compared to older pts ) are ↑ likely to be diagnosed following an emergency presentation
 Inflammatory bowel diseases → mainly UC and Crohn’ss share several symptoms with CRC -
○ rectal bleeding
○ abdominal pain
○ diarrhoe
○ weight loss
○ anaemia
 For younger patients delayed diagnosis is common for both IBD/ CRC

○ CRC- clear relationship between diagnostic delay and more advanced disease , complications and emergency presentation , and with mortality
 Ten features were independently associated with CRC/ IBD

○ Rectal bleeding ○ CIBH ○ Diarrhoe ○ Raised inflammatory markers ○ Thrombocytosis ○ Abdominal pain ○ Low haemoglobin 
○ Low MCV ○ Raised WCC ○ Raised hepatic enzymes
 Rectal bleeding and CIBH are strongly predictive of CRC/ IBD when combined with abnormal haematology

Question to ask →” Which younger patients with symptoms would benefit from investigations for potentially serious colorectal disease ?”

Aged 40 and over with unexplained weight loss and abdominal pain or
 Aged 50 and over with enexplained rectal bleeding or
 Aged 60 and over with

○ Iron deficiency anaemia or
○ Changes in their bowel habit 
 Tests show occult blood in faeces*
 Rectal or abdominal mass

Abdominal pain Change in bowel habit Weight loss Iron-deficiency anaemia

Adults without rectal bleeding

 Aged 50 and over with unexplained
○ abdominal pain or
○ weight loss or
 Age under 60 with
○ CIBH or
○ Iron deficiency anaemia
 Aged 60 and over and have anaemia in the abscence of iron deficiency

References Diagnosis and management of colorectal cancer SIGN Guideline 126 Aug 2016 Oxford Handbook of Oncology Oxford university Press Aug 2015 ABC of Colorectal Cancer -BMJ Books 2011 Bowel Screening CKS NHS Gastrointestinal tract ( lower ) cancers- recognition and referral NICE Nov 2015 Colorectal cancer overview NICE Pathways Cancer Research UK ; Bowel cancer Colon Cancer Medscape Tomislav Dragovich et al March 2017 Clinical features of bowel disease in patients aged < 50 years in primary care : a large case-control study Br J Gen Pract March 2017

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