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Acinic cell carcinoma is a salivary gland cancer, almost always of the parotid gland, whose cells resemble the gland's normal enzyme-making cells. It is usually low grade and slow, presenting as a painless lump that is easily mistaken for a benign tumour, and surgery cures most; a high-grade minority behaves aggressively and needs radiotherapy too.

Adamantinoma is a very rare, slow-growing bone cancer of young adults that almost always affects the shin bone, made of epithelial cells inside fibrous bone, and listed with the bone sarcomas in the WHO classification. It is cured by cutting it out with a margin; chemotherapy and radiotherapy do not work, and a minority spread to the lungs many years later.

Adenocarcinoma of the urethra is a gland-forming type of urethral cancer, more often seen in women, that can start in the small glands beside the urethra or in a pouch (diverticulum) in its wall. The clear cell form is its own entity in the WHO classification. No trial has been run in it, so it is treated by surgery at a specialist urological centre, advanced disease as on the parent page.

Adenosquamous carcinoma of the cervix is an uncommon cervical cancer containing both gland-forming and squamous cancer cells. Like cervical adenocarcinoma it is caught less well by smear screening and does somewhat worse than squamous cancer stage for stage, but it is treated the same way, with surgery when early and chemoradiation when advanced.

Adrenocortical carcinoma is a rare, aggressive cancer of the adrenal gland that often over-produces hormones. Surgery is the only cure, mitotane is the one drug specific to it (with real toxicity), and chemotherapy or immunotherapy help only a minority.

Ampullary cancer, a biliary tract cancer, starts where the bile and pancreatic ducts empty into the small bowel. Because it blocks bile flow early it is often caught while still removable, and the Whipple operation cures a good share of patients. Tumours come in two flavours, intestinal-like and pancreas-like, and chemotherapy is increasingly chosen by which one the pathologist sees.

Rare tumours of the appendix that range from slow mucin-producing growths that fill the abdomen (pseudomyxoma peritonei) to aggressive adenocarcinomas. The slow forms are treated by extensive surgery with heated chemotherapy in the abdomen; the fast ones like colon cancer.

Bartholin gland carcinoma is a very rare vulvar cancer arising in the lubricating glands at the entrance to the vagina, often mistaken at first for a cyst or abscess in a postmenopausal woman. It can be a squamous cancer, an adenocarcinoma or an adenoid cystic carcinoma, each behaving differently; it is treated with surgery and radiotherapy borrowed from vulvar cancer, having no trials of its own.

Blastic plasmacytoid dendritic cell neoplasm is a rare aggressive leukaemia-like blood cancer of dendritic-cell precursors, a few hundred US cases a year, that often first appears as bruise-like skin lesions. Two CD123-directed drugs, tagraxofusp and pivekimab sunirine, are the first targeted therapies; allogeneic transplant in first remission is still the only route to long-term control.

Burkitt leukaemia is Burkitt lymphoma presenting mainly in the bone marrow and blood, so that it looks like acute lymphoblastic leukaemia but is a mature B-cell cancer driven by the MYC gene. It is treated as Burkitt lymphoma, with short, very intensive chemotherapy plus rituximab and protection of the brain, and most children and many adults are cured.

Carcinoma ex pleomorphic adenoma is a salivary gland cancer that grows out of a long-standing benign pleomorphic adenoma, the commonest salivary tumour, usually in the parotid. Its outlook depends on how far the cancer has grown beyond the old adenoma's capsule: cancers still inside it are cured by surgery, while widely invasive ones need radiotherapy and do poorly.

Chordoma is a slow-growing bone cancer (a sarcoma) of the skull base and spine that arises from leftover embryonic notochord cells. Complete surgery followed by high-dose proton or carbon-ion radiotherapy controls most tumours, and the whole disease depends on a single transcription factor, brachyury, which vaccines and degraders are now trying to hit.

Choriocarcinoma is the rarest and most dangerous form of non-seminoma testicular cancer, made of placenta-like cells that pour out the pregnancy hormone hCG and spread early through the blood to the lungs, liver and brain, where they can bleed. Fewer than eight in ten men survive five years, against more than 95 for testicular cancer overall, so it is treated urgently with intensive chemotherapy.

Choroid plexus carcinoma is a rare, aggressive brain tumour of infants and young children that grows from the tissue that makes spinal fluid inside the brain's ventricles, causing fluid build-up and pressure. It is strongly linked to an inherited TP53 fault (Li-Fraumeni syndrome), so families are tested; treatment is surgery, then chemotherapy and, in older children, radiotherapy.

Chronic myelomonocytic leukaemia and its relatives are bone-marrow cancers that behave partly like myelodysplasia (poorly made blood cells) and partly like a proliferative disease (an excess of monocytes or platelets). Hypomethylating agents produce responses in a minority and stabilise counts in more, transplant can cure the fit, and RAS-pathway and JAK inhibitors are in trials.

Clear cell papillary renal cell tumour is a small, low-grade kidney tumour that looks like a mix of clear cell and papillary kidney cancer but behaves harmlessly: no case has been reported to spread. The WHO renamed it from carcinoma to tumour in 2022 for that reason. It is common in people with kidney failure and is cured by removing it.

Collecting duct carcinoma is a rare, aggressive kidney cancer that starts in the tubes deep in the kidney that collect urine. It is treated with surgery where possible and the platinum chemotherapy used for bladder cancer, not the usual kidney cancer drugs, which do not work in it. It is usually advanced when found: 74.4 percent of 286 US SEER patients were stage III or IV.

Conjunctival melanoma is a rare melanoma of the clear membrane over the white of the eye, usually growing out of a flat brown patch called primary acquired melanosis. It is removed with a margin and the edges frozen or treated with chemotherapy drops; about one in five spread within five years, and advanced disease is treated like skin melanoma with targeted or immune drugs.

A corticotroph tumour is a pituitary tumour of the cells that make ACTH. When it secretes it floods the body with cortisol, causing Cushing disease (weight gain, diabetes, high blood pressure, thin skin); the silent form is found as a large non-functioning mass. Surgery through the nose is the main treatment; cortisol-lowering drugs, repeat surgery or radiotherapy follow for those not cured.

Dedifferentiated chordoma is a rare form of chordoma in which part of the tumour has turned into a high-grade sarcoma, usually after recurrence or radiotherapy but sometimes from the start. The sarcoma part decides the outcome and made up 3 to 95 percent of the tumour in the defining series, smaller areas doing better, so it is treated with surgery and sarcoma chemotherapy.

Desmoid tumours are locally aggressive growths of fibroblast-like cells, classed with soft-tissue sarcomas, driven by WNT mutations, that never spread to distant organs but can invade nerves, bowel and muscle. Many stop growing or shrink on their own, so watching first is standard; if they progress, the gamma-secretase inhibitor nirogacestat, approved in 2023, shrinks tumours and relieves pain.

Desmoplastic small round cell tumour is a very rare sarcoma of adolescents and young men that grows across the lining of the abdomen as many nodules, driven by an EWSR1-WT1 fusion. Treatment is intensive chemotherapy, surgery to remove every nodule, sometimes heated abdominal chemotherapy, and radiotherapy. Most still relapse within three years, so it is treated at a sarcoma centre running trials.

Embryonal carcinoma is the most aggressive and most common building block of non-seminoma testicular cancer, made of primitive cells that resemble an early embryo and can turn into the other tumour types. On its own or as the main component it spreads early to lymph nodes and lungs, but it is highly sensitive to cisplatin chemotherapy and most men are cured.

Eosinophilic solid and cystic renal cell carcinoma is a recently named kidney cancer, almost always in women, made of pink cells in solid areas and cysts. It was first seen in people with tuberous sclerosis and then found on its own, it is nearly always confined to the kidney, and surgery cures it in almost every reported case.

Epithelioid sarcoma is a rare soft tissue cancer that has lost a gene brake called SMARCB1, leaving it dependent on the enzyme EZH2. Surgery cures localised tumours. The EZH2 inhibitor tazemetostat was approved in 2020 and withdrawn worldwide in March 2026 after secondary blood cancers in a lymphoma trial; the dependency it proved is still a target in development, and chemotherapy remains in use.

Histiocytoses are diseases in which immune scavenger cells build up in bone, heart, brain, kidneys and skin. They used to be treated as inflammatory conditions with steroids and interferon. The discovery that most carry mutations in the same growth pathway as melanoma turned them into targetable cancers: BRAF and MEK inhibitor pills now produce responses in nearly every treated patient.

Extragonadal germ cell tumours are the same cancers as testicular germ cell tumours but arising in the midline of the body, most often the chest or the back of the abdomen. Seminomas are highly curable with chemotherapy; non-seminomas of the chest are the hardest germ cell tumours to cure and are treated with intensive chemotherapy followed by surgery.

MALT lymphoma is a slow-growing lymphoma that starts in lymphoid tissue lining an organ, most often the stomach, where it is usually caused by long-standing Helicobacter pylori infection and can be cured with antibiotics alone. Other sites include the eye socket, salivary glands, thyroid, lung and skin; localised disease is treated with low-dose radiotherapy and widespread disease with rituximab.

Fumarate hydratase-deficient renal cell carcinoma is a rare, aggressive kidney cancer in which the FH gene is lost, most often because the person was born with a faulty copy as part of the HLRCC syndrome, which also causes skin and womb fibroids. It strikes younger adults, is found by a stain for the missing enzyme, and needs family testing; advanced disease gets the usual kidney cancer drugs.

Gallbladder cancer starts in the small bile-storing sac under the liver and is one of the biliary tract cancers. Most cases are found late, or by chance when a gallbladder is removed for gallstones. It is rare in the UK, with about 1,300 cases a year, and much commoner in Chile, Bolivia and northern India. Found early, an operation can cure it.

Germ cell neoplasia in situ is the pre-cancer of testicular germ cell tumours: abnormal fetal-type germ cells sitting inside the seminiferous tubules, which will become seminoma or non-seminoma if left. It is found beside almost every testicular cancer and sometimes on its own in the other testis, where low-dose radiotherapy or surgery prevents a second cancer.

Cancers that grow from placental tissue after a pregnancy. They make a hormone (hCG) that acts as a perfect blood test, and they were the first solid cancer ever cured by chemotherapy. Immunotherapy now rescues the few that resist drugs.

Glucagonoma is a very rare pancreatic neuroendocrine tumour that pours out the hormone glucagon, causing weight loss, diabetes and a distinctive migrating red rash. Because the rash is so characteristic, spotting it early can lead to diagnosis before the tumour has spread to the liver; surgery is the definitive treatment and somatostatin analogues control the symptoms.

A gonadotroph tumour is a pituitary tumour of the cells that normally make the fertility hormones, but it almost never secretes enough to cause symptoms, so it is found as a large non-functioning mass pressing on the optic nerves or by chance. Surgery through the nose is the treatment when it threatens vision or grows; there is no drug for it, and radiotherapy is used for regrowth.

Hepatosplenic T-cell lymphoma is a rare, very aggressive lymphoma of young men in which gamma-delta T cells fill the liver, spleen and bone marrow without forming lumps in the nodes. It is linked to long-term immune suppression, above all thiopurines with or without anti-TNF drugs for inflammatory bowel disease, and is treated with intensive chemotherapy then a stem cell transplant where possible.

People living with HIV have a raised risk of aggressive lymphomas, driven by immune suppression and viruses such as Epstein-Barr virus. The transformation of the last two decades is that, with antiretroviral therapy continued through treatment, these lymphomas are treated with the same full-dose chemotherapy and antibody regimens as in anyone else, with similar chances of cure.

Hyperparathyroidism-jaw tumour syndrome is an inherited condition in which a faulty CDC73 gene causes parathyroid tumours, and in about one in five people a parathyroid carcinoma, together with bony tumours of the jaw and kidney and womb growths. It matters because it is the commonest inherited route to parathyroid carcinoma and a reason to test the gene in anyone with that cancer.

IMT is a rare tumour, grouped with the sarcomas, of spindle cells mixed with inflammatory cells, most often in the lung or abdomen of children and young adults. Surgery cures most, and about half carry an ALK gene fusion, so the ALK-blocking pill crizotinib is approved for those that cannot be removed, one of the first targeted approvals for a childhood solid tumour.

Intravascular large B-cell lymphoma is a rare form of large B-cell lymphoma in which the cancer cells grow inside small blood vessels rather than forming lumps, so it causes fevers, confusion, skin patches or breathlessness and is often found late or only after death. Rituximab-based chemotherapy with drugs that reach the brain has turned a nearly always fatal disease into one often controlled.

A prolactinoma is a pituitary tumour of the cells that make prolactin, the milk hormone; it is the commonest hormone-producing pituitary tumour and causes missed periods, infertility, milk production or, in men, low testosterone. Almost uniquely among tumours it is treated first with a tablet, cabergoline, which shrinks it in most people; surgery is kept for those the drug fails.

Leydig cell tumour is the commonest testicular tumour that is not a germ cell tumour; it grows from the hormone-making cells between the tubules. It often makes testosterone or oestrogen, causing early puberty in boys or breast growth in men, and nine in ten are benign and cured by surgery. No chemotherapy works in the malignant tenth, managed case by case at a specialist centre.

Lymphomatoid granulomatosis is a rare Epstein-Barr virus-driven disease of B cells that invades and destroys blood vessels, almost always in the lungs and often the brain and skin, in people whose immune control of the virus is weak. Low-grade disease can be treated with interferon and high-grade disease as a large B-cell lymphoma with rituximab-based chemotherapy.

Men get breast cancer too, usually a hormone-sensitive kind found as a lump near the nipple. It is treated much as in women, with surgery, radiotherapy and tamoxifen, and inherited BRCA2 mutations are found often enough that every man diagnosed is offered genetic testing. The main fix under way is including men in trials so their care stops being borrowed from women.

A mediastinal germ cell tumour is a germ cell tumour that starts in the chest, between the lungs, rather than in the testis. Seminomas here are cured almost as often as testicular seminoma, but non-seminomas of the chest are the hardest germ cell tumours to cure, so they get four cycles of chemotherapy and surgery for what is left.

Melanoma of the urethra is a very rare urethral cancer that starts in pigment cells of the urethral lining, usually near its outer opening, in older adults. It is a form of mucosal melanoma, so it is removed surgically and, when it spreads, treated with the immunotherapy drugs used for melanoma elsewhere.

Merkel cell carcinoma is a rare, fast-growing skin cancer, usually caused by a common virus (Merkel cell polyomavirus) or by sun damage. Once it had spread there was no treatment that worked; PD-1/PD-L1 immunotherapy now gives lasting responses in about half of patients.

Micronodular thymoma with lymphoid stroma is a rare, benign-behaving thymoma made of small nests of spindle-shaped epithelial cells separated by abundant B lymphocytes, unlike other thymomas whose lymphocytes are T cells. It is cured by surgery; its curiosity is that a third harbour a clonal B-cell population, and a few develop a low-grade lymphoma within the tumour.

Mixed-phenotype acute leukaemia is a rare acute leukaemia whose cells carry markers of both lymphoid and myeloid lines, so it fits neither acute lymphoblastic nor acute myeloid leukaemia. Pooled evidence favours starting with the drugs used for acute lymphoblastic leukaemia, adding a targeted drug when the Philadelphia chromosome is present, and a stem cell transplant in first remission.

Mucinous tubular and spindle cell carcinoma is a rare, usually slow-growing kidney cancer, commoner in women, whose cells form small tubes and spindles in a mucus-rich background. It is driven by loss of the Hippo growth-control pathway rather than the faults of common kidney cancer, and surgery cures most cases.

The MEN syndromes are inherited faults in a single gene that cause tumours in several hormone glands over a lifetime. Because the gene can be found in childhood, at-risk relatives can be tested, watched and in MEN2 have the thyroid removed before cancer develops; and for MEN2 thyroid cancer that does spread there is now a precise pill, selpercatinib, that blocks the faulty RET protein.

MEN1 is an inherited condition, one of the multiple endocrine neoplasia syndromes, in which a faulty MEN1 gene lets tumours grow in the parathyroid glands, the pancreas and the pituitary. Each tumour is treated much as it would be in anyone else, but because there are many of them and they come back, families are followed for life in specialist clinics.

MEN2 is an inherited condition, one of the multiple endocrine neoplasia syndromes, in which a faulty RET gene causes medullary thyroid cancer in almost every carrier, often with adrenal tumours and overactive parathyroids. Because the thyroid cancer is so predictable, children who inherit the gene have the thyroid removed at an age set by which RET mutation they carry.

Myeloid leukaemia of Down syndrome is a form of acute myeloid leukaemia in young children with Down syndrome, driven by a GATA1 mutation on top of the extra chromosome 21 and often preceded by a transient leukaemia-like illness in the newborn. Its cells are unusually sensitive to chemotherapy, so children are cured about nine times in ten with gentler treatment than other childhood leukaemia.

Cancers of the nose and sinuses are a mixed group, from squamous carcinoma to the nerve-derived esthesioneuroblastoma and the aggressive undifferentiated carcinoma SNUC. Surgery through the nose with an endoscope followed by precise radiotherapy has replaced disfiguring open operations, and giving chemotherapy first to see who responds now guides how SNUC is treated.

Nodal marginal zone lymphoma is a slow-growing lymphoma of the lymph nodes that looks like the MALT and splenic types under the microscope but has no organ or spleen involvement to explain it. It lacks a diagnostic marker, so it is diagnosed by excluding the other small B-cell lymphomas, and it is treated like follicular lymphoma with rituximab-based therapy.

Angioimmunoblastic T-cell lymphoma, now called nodal T-follicular helper cell lymphoma of angioimmunoblastic type, is one of the commonest T-cell lymphomas and mostly affects people over 60. It presents with widespread swollen nodes, fever, rash and immune upsets such as anaemia; about four in ten people are alive five years after chemotherapy, more after a transplant in first remission.

NUT carcinoma is a fast-growing cancer of the midline of the body driven by a single fused gene, BRD4-NUTM1, that locks cells in an immature state. Chemotherapy and surgery rarely control it for long, but drugs that block the BET proteins the fusion depends on have produced responses and are the focus of trials.

Optic pathway glioma is a slow-growing childhood brain tumour of the nerves that carry sight, often in children with neurofibromatosis type 1. It rarely kills but can take away vision, so treatment aims to preserve sight: watching if stable, chemotherapy such as carboplatin and vincristine if vision is threatened, or the MEK-blocking tablet selumetinib, with radiotherapy avoided in young children.

Papillary tumour of the pineal region is a rare brain tumour of young adults arising near the pineal gland from cells of the embryonic subcommissural organ. It usually presents with raised pressure from blocked spinal fluid, is removed surgically at a centre that does pineal surgery and often given radiotherapy, and it recurs locally more often than it seeds the spine.

Parathyroid carcinoma is a cancer of the glands that control blood calcium, seen in a few people per ten million a year; most of its harm comes from dangerously high calcium rather than spread. Removing the tumour intact at the first operation gives the best chance of cure, and cinacalcet and bone-protecting drugs control calcium when it cannot be removed.