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The adenoma detection rate is the share of screening colonoscopies in which an endoscopist finds at least one adenoma. It is the best single measure of how good a colonoscopy service is, because the patients of endoscopists who find more polyps go on to get fewer cancers and to die of them less often.

The adenoma-carcinoma sequence is the step-by-step route by which a normal bowel lining becomes a polyp and the polyp becomes a cancer, as genetic faults pile up over years. It is why removing polyps prevents cancer, and it was the first human cancer to be mapped this way.

Adenoma-like adenocarcinoma is a form of bowel cancer whose invasive part still looks like a harmless polyp under the microscope, which is why it is often reported as an adenoma on biopsy and only recognised once the bowel is removed. Despite frequently growing deep into the bowel wall, it spreads to lymph nodes less often than ordinary bowel cancer and does better.

Adenosquamous carcinoma is a rare form of pancreatic cancer in which at least three tenths of the tumour has turned into squamous cells, the flat cells of skin-like linings. It is found more often in the body and tail, tends to be larger and poorly differentiated, and does worse after surgery than ordinary pancreatic cancer, though surgery remains the strongest predictor of survival.

When an EGFR antibody stops working, the resistant cells that caused it fade away once the drug is withdrawn. Rechallenge means giving the same class of drug again later, after a blood test has confirmed those resistant clones have receded, and in small trials about a fifth to a third of patients respond a second time.

Cholangiocarcinoma is cancer of the bile ducts or gallbladder. It is rare and often found late, but it turned out to carry more targetable mutations than almost any other gastrointestinal cancer, and immunotherapy now adds to chemotherapy from the first treatment.

A carer is anyone giving unpaid help to someone with cancer who could not manage without it. You can come to appointments and write down the answers, learn the sepsis, blockage and stoma signs, help with bags and supplies if asked, tell the team you are the carer, ask the council for a free carer's assessment, and use Bowel Cancer UK's nurses, forum and carer pages for yourself.

A carer is anyone giving unpaid help to someone with cancer who could not manage without it; you can come to appointments, keep the enzyme dose and the medicine list, learn the sepsis, stent, clot and blocked-bowel signs, tell the team you are the carer, ask the council for a free carer's assessment, and use Pancreatic Cancer UK's nurses, carer booklet and Circles community for yourself.

The circumferential resection margin is the side surface of the removed rectum, the plane the surgeon cut along. If cancer cells lie within a millimetre of it, the cancer is much more likely to come back in the pelvis. It is measured on the scan before surgery and on the specimen afterwards, and it is the single reading that most shapes rectal cancer treatment.

Gene expression divides pancreatic ductal adenocarcinoma into two main types: classical, the commoner, which keeps its pancreatic identity and responds better to chemotherapy, and basal-like or squamous, which has lost it and carries a worse outlook. One gene, GATA6, is high in classical and low in basal-like tumours, so it can stand in for the whole test; it is used in trials, not routine care.

Clinical benefit response was the measure invented for the 1997 trial that got gemcitabine approved for pancreatic cancer: a patient counted as benefiting if pain, painkiller use, day-to-day function or weight improved for at least four weeks without any of the others getting worse. It is a symptom endpoint, and it is why gemcitabine was accepted on a survival gain of about five weeks.

An injection that deadens the bundle of nerves behind the pancreas, done through the back under X-ray or ultrasound guidance or from inside the stomach during an endoscopic ultrasound; NICE suggests considering it when pancreatic pain is not controlled, opioid side effects are unacceptable or doses keep rising.

Colibactin is a DNA-damaging chemical made by some strains of gut bacteria. It leaves a recognisable pattern of mutations in bowel cancers, that pattern is commoner in people diagnosed young, and it is the strongest current lead on why bowel cancer is rising in the under-50s.

Colloid carcinoma is a rare form of pancreatic cancer in which the cancer cells float in large pools of mucus rather than forming glands in dense scar. It usually grows out of an intestinal-type IPMN in the main pancreatic duct, presents as a larger but lower-stage tumour, and has a clearly better outlook after surgery than ordinary pancreatic cancer.

The cancer where screening works best and where immunotherapy can make some tumours disappear entirely; chemotherapy still carries most metastatic disease, now with antibodies and targeted combinations chosen by RAS, BRAF, mismatch repair and which side of the bowel the tumour started on.

Bowel cancer grows from a polyp over years, so removing the polyp prevents it. This roadmap follows the evidence from that discovery through the stool tests and scopes that built the screening programmes, the operation that changed rectal cancer, the chemotherapy and antibody era, immunotherapy that dissolves some tumours without surgery, and the unexplained rise in young adults, to 2032.

Conversion therapy means giving drugs to shrink secondary tumours that cannot be operated on at first, in the hope that they become small enough to remove. It is a different goal from simply controlling the disease: the treatment is chosen for how hard it shrinks the tumour, and the scans are reviewed by a surgeon every couple of months.

Some bowel cancers switch off large numbers of genes at once by chemically tagging their control regions rather than by mutating them. That state travels with BRAF mutation, with the serrated route to cancer and with the accidental loss of DNA proofreading, and it is how most bowel cancers with unstable microsatellites arise without an inherited fault.

Cytoreductive surgery is an operation that strips every visible tumour deposit from the lining of the abdomen and from the organs it coats, often taking many hours. In bowel cancer that has spread only to that lining, it is the part of treatment that does the work: the heated chemotherapy added at the end of it was tested in a randomised trial and made no difference.

Distal pancreatectomy removes the body and tail of the pancreas, the part to the left of the main vessels, usually with the spleen when the cause is cancer. The bile duct and duodenum are left alone, so there is no Whipple-type reconstruction; keyhole and robotic versions recover faster and, in a randomised trial, removed pancreatic cancer as completely as open surgery.

After a Whipple operation the stomach can be slow to empty for days or weeks, meals feel full quickly, and pale, oily stools mean enzymes are needed; small frequent meals, enzyme capsules with everything, a dietitian's review and patience over several months are the pattern most people describe.

An emergency presentation means a cancer was diagnosed after the person arrived as an emergency, through A&E or an urgent admission, rather than through a GP referral or screening. It is the route with the worst survival because the cancer is usually advanced by then. Almost half of pancreatic cancers in England are diagnosed this way, more than for almost any other common cancer.

Extended RAS testing looks for mutations across KRAS and NRAS, not just the one spot that was tested first. It decides who can have an EGFR antibody: the drugs work only when every one of those spots is normal, and testing the wider set moved about one patient in six out of the group offered them.

The guaiac faecal occult blood test was the first stool test used for bowel screening: six smears from three separate stools, read by a colour change when blood is present. It is the test that proved in randomised trials that bowel screening saves lives, and England replaced it with the more accurate and easier faecal immunochemical test in 2019.

In familial adenomatous polyposis a person inherits a fault in the APC gene and grows hundreds or thousands of polyps in the large bowel from their teens. Left alone, almost all of them become cancer by about 40, so the bowel is watched from childhood and usually removed before that happens; the cancers that do occur are treated like ordinary bowel cancer.

Familial pancreatic cancer means at least two close relatives on the same side of the family have had the disease without a known gene fault to explain it. Members of such families have several times the usual risk, rising steeply with the number of relatives affected. With carriers of certain gene faults, they are the people offered yearly MRI or endoscopic ultrasound in surveillance programmes.

A cancer with three new targets in five years: Claudin 18.2, FGFR2b, and HER2 with new ADCs, plus immunotherapy in first line.

Liver cancer almost always grows in a liver already damaged by hepatitis, alcohol or fatty liver disease. It is one of the most preventable cancers, and since 2020 immunotherapy combinations have roughly doubled how long people with advanced disease live.

Bowel cancer needed its own rule for calling a tumour HER2-positive, because the rules written for breast and stomach cancer did not transfer. The HERACLES criteria are that rule: intense membrane staining in more than half the cells, confirmed by gene amplification, which finds about one in twenty RAS wild-type bowel cancers.

Most pancreatic cysts never become cancer, so doctors watch them and operate only when warning signs appear. The strongest signs, the high-risk stigmata, are jaundice from a cyst in the head of the pancreas, a solid lump inside the cyst that lights up with dye, or a main duct widened to a centimetre or more. Lesser signs, the worrisome features, prompt a closer look with endoscopic ultrasound.

The Immunoscore counts the immune cells inside a bowel tumour and at its invading edge and turns the density into a single score. People with a high score relapse far less often than people with a low one, whatever their stage, and the score adds information the stage does not.

An interval cancer is one diagnosed after a screening test or a colonoscopy that found nothing, and before the next test was due. Every screening programme has them. Counting them honestly is how a programme finds out what it is missing, and in the bowel most of them come from lesions that were there and were not seen.

IPMN-associated carcinoma is pancreatic cancer that has grown out of a mucus-producing cyst in the pancreatic duct. Because the cyst is often being watched, the cancer is found smaller and earlier, and about four in ten patients are alive five years after surgery against two in ten for ordinary pancreatic cancer; the advantage belongs to the colloid type, not the tubular type.

About one person in ten to twenty cannot make the sugar that the CA 19-9 blood test measures, because they lack a working copy of the Lewis blood-group gene. In these Lewis-negative people the test stays low however large the cancer, so a normal CA 19-9 does not rule pancreatic cancer out, and their cancers appear to behave more aggressively.

Bowel cancer that has spread only to the liver, and sometimes only to the lung, is one of the few forms of secondary cancer treated with the aim of cure. If the deposits can be removed or destroyed, with chemotherapy before and after, a substantial minority of people are alive five years later.

A colostomy or ileostomy after bowel cancer surgery may be temporary, to let a join heal, or permanent. Recovery takes about eight weeks, bags come as one-piece or two-piece and drainable or closed, permanent colostomy supplies are free on prescription, and the emergencies to know are a blockage (nothing coming out, cramps, sickness, swelling), heavy bleeding, dehydration and signs of infection.

The three main regimens share low blood counts, tiredness, sickness and sore mouth; FOLFIRINOX and NALIRIFOX add irinotecan diarrhoea and oxaliplatin's cold-triggered tingling and rare throat spasm, gemcitabine with nab-paclitaxel adds hair loss and neuropathy, and every regimen comes with the same temperature rule for ringing the 24-hour line.

The bowel cancer regimens share low blood counts, tiredness, sickness and a sore mouth. Oxaliplatin adds cold-triggered tingling, irinotecan adds early and late diarrhoea, capecitabine adds hand-foot syndrome and needs a DPD test first, and cetuximab or panitumumab add an acne-like rash and low magnesium. The rule for all of them: ring the 24-hour number rather than wait.

The group of bowel problems that can follow sphincter-preserving surgery for rectal cancer: going more often, urgency with or without leaking, feeling the bowel is not empty, passing small amounts little and often, and not being able to tell wind from stool. NICE asks teams to warn people before surgery, to measure it with the LARS score and to treat it in primary care.

Every bowel cancer should be tested for mismatch repair loss, and where it is found, for whether that loss is inherited. A Lynch syndrome result changes your treatment options, gives each of your children and siblings a one in two chance of carrying it, and puts you into regular colonoscopy; NICE also says to consider daily aspirin for more than two years.

Lynch syndrome-associated bowel cancer is bowel cancer in someone born with a fault in one of the genes that proofread DNA copying errors. The tumours tend to arise younger and on the right side, they carry the mismatch repair defect that makes immunotherapy work, and the diagnosis changes the care of the whole family as well as the care of the patient.

Micropapillary adenocarcinoma is bowel cancer in which some of the tumour grows as tiny clusters of cells floating in empty spaces, with the cells turned inside out so the surface that normally faces the bowel faces outwards instead. It is a pattern that goes with heavier invasion of lymph and blood vessels and more involved lymph nodes, and it is graded and treated like ordinary bowel cancer.

MCN-associated carcinoma is pancreatic cancer that has developed inside a mucinous cystic neoplasm, a thick-walled cyst with ovary-like tissue in its wall that occurs almost only in women, usually in the tail of the pancreas. Most such cysts are benign when removed; the minority with invasive cancer are larger, carry nodules and occur in older women, and about six in ten survive five years.

For pancreatic cancers that look removable, doctors debate whether to operate at once and give chemotherapy afterwards, or to give chemotherapy first. Trials show chemotherapy first helps when the tumour is borderline, touching the big vessels, but it is not yet proven better for clearly removable tumours, where the largest trial found no gain and a US trial is still running.

A pancreatic cancer can cause diabetes before any other symptom, so new diabetes after the age of 50, especially with weight loss rather than weight gain, is a recognised warning sign. About one in a hundred such people is found to have pancreatic cancer within three years; a simple score using weight change, blood sugar change and age picks out the smaller group who should have a scan.

The NHS posts a home test for hidden blood in the poo to everyone aged 50 to 74 in England every two years. Most people are told no further tests are needed; if blood is found they are offered a colonoscopy. It is the only NHS cancer screening programme that can prevent the cancer as well as find it early, because the colonoscopy removes the polyps.

Sometimes a bowel cancer is found only when it blocks the bowel or has grown through its outer wall into the peritoneum or a neighbouring organ. Both change the plan: a blockage may be relieved with a stent so that surgery can be done calmly a few weeks later, and a tumour that has grown outside the bowel may be given chemotherapy first.

Oesophageal cancer is really two diseases sharing one organ: squamous cell carcinoma, which dominates in Asia, and adenocarcinoma, which dominates in the West and is treated like gastric cancer. Immunotherapy is now standard, and the bispecific ADC iza-bren posted a positive phase 3 in the squamous type in 2026.

A pancreas protocol CT is a scan tuned for the pancreas: thin slices taken at two timed moments after contrast dye so that the tumour, the arteries and the veins all show up sharply. It is the first test NICE asks for when pancreatic cancer is suspected, before any stent is placed, and the report follows a template that lists every vessel the tumour touches and by how many degrees.

Pancreatic cancer has had one operation since 1935 and a handful of chemotherapy drugs since 1997. This roadmap follows the evidence through FOLFIRINOX, chemotherapy before and after surgery, the first inherited-gene drug, the first drugs against the KRAS protein that drives nearly every tumour, personalised vaccines, and the surveillance and blood tests that might catch it earlier, to 2031.

Almost every pancreatic tumour carries a KRAS mutation, and for the first time drugs against it work: daraxonrasib nearly doubled survival in previously treated disease in 2026. Pancreatic cancer has been the hardest common cancer to treat once advanced; that is what is starting to change.

Most pancreatic cancers stop the gland's digestive enzymes reaching the gut, so fat passes through undigested and weight falls. Enzyme capsules taken with every meal and snack replace what is missing. NICE says everyone whose cancer cannot be removed should have them and that they should be considered before and after surgery, yet in UK records only about one patient in five was prescribed them.

PanIN is the name for abnormal cells lining the small pancreatic ducts that can, over years, turn into pancreatic cancer. It is too small to see on any scan and is found only under the microscope, so it cannot be screened for directly. Pathologists now grade it as low or high grade, and high-grade PanIN was found in about one in twenty-five older people who died without pancreatic cancer.

The peritoneal cancer index is the score a surgeon gives the abdomen at operation, region by region, for how much tumour is on its lining. It decides whether stripping the disease out is worth attempting, and it is the number quoted when a specialist centre says a person is or is not a candidate.

Bowel cancer can seed the lining of the abdomen rather than travel to the liver or lungs. Where the deposits are confined to that lining and can all be removed, specialist centres offer an operation to strip them out. Adding heated chemotherapy into the abdomen at the end of that operation was tested in a randomised trial and did not help.

A polyp is a growth on the lining of the bowel. Most are harmless, but two families can turn into cancer: adenomas, the classic route, and serrated lesions, the flatter and easier-to-miss route. Which kind you had, how many, how big and whether the cells looked abnormal decide when you are asked back.

R-spondin fusions are rearrangements that make a bowel tumour overproduce a protein which turns the Wnt growth pathway up from outside the cell. They occur in about one colon tumour in ten and almost never alongside the usual APC fault, so they look like an alternative way into the same pathway.

After a pancreatic cancer is removed, the pathologist checks whether cancer reaches the cut edges of the specimen. In the UK, cancer within one millimetre of an edge counts as an incomplete (R1) resection even if it does not touch it. Reported this way most operations are R1, because the tumour creeps along nerves behind the gland; cancer touching the edge carries a worse outlook.

Surgeons class a pancreatic cancer as resectable, borderline resectable or locally advanced by how far it wraps around the arteries and veins behind the pancreas on the CT scan, measured in degrees of contact. Less than half way round an artery, or a vein the surgeon can rebuild, is borderline; more is locally advanced. A very high CA 19-9 or poor fitness can also make a tumour borderline.

Uptake is the share of people invited to screening who actually take the test. It decides how much good a programme does, because a test nobody returns prevents nothing, and it is lower in more deprived areas, which turns a programme meant to close a gap in outcomes into one that can widen it.