Colorectal cancer ( CRC )

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

Third most deadly and 4th most commonly diagnosed cancer worldwide 4th most common cancer in UK accounting for 11 % of all new cancer cases in 2017 Slightly ↑ common in men More common in the developed than developing world Incidence ↑ es with age ( except familial colorectal cancer ) in the UK during 2015-17 on average each year more than 4 in 10 new cases were in people aged 75 and over Highest rate are in 85-89 age group Incidence increasing worldwide and mortality decreasing ( Western way of life ) Almost always adenocarcinoma

What happens -almost always arises from benign neoplasms called tubular adenomas and serrated polyps which evolve into CRC over several years ie polyp-cancer progression is slow many adenomas begin as small polyps which enlarge and become dysplastic and eventually cancerous environmental factors are important in the aetiology of the disease CRC arises from epithelial lining most often as a consequence of mutations in the signaling pathways Underlying molecular changes have largely been identified Most CRC are localized with or without lymph node metastases

Risk factors...