Rare cancers that challenge the medical profession -

Cancer is a large group of diseases that can start in almost any organ or tissue of the body. There are more than 100 types of cancer, and just over a quarter are considered rare, including all children's cancers. Approximately one in five people living with cancer in the United States are diagnosed with a rare cancer. Rare cancers are challenging for patients, doctors, and scientists alike. In fact, a few are so uncommon that no clinical trial results, meta-analyses, or treatment guidelines exist. While most rare cancers are aggressive, quick spreading, and offer up a grim prognosis, others are benign and can be treated effectively.

So, just how scarce are these little-known cancers, and how dangerous are they? Click through for a diagnosis.

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Chronic myeloid leukemia -

Chronic myeloid leukemia (CML) causes the bone marrow to make abnormally high numbers of blood cells in the body, which then start to grow out of control. CML occurs mostly in adults, but in very rare cases is found in children as well.

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Glioblastoma -

A fast-growing and extremely aggressive brain tumor, glioblastoma is actually the most common malignant primary brain tumor. However, incidences of the disease range globally from 0.59 to 5 per 100,000 persons.

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Childhood acute lymphoblastic leukemia -

While childhood acute lymphoblastic leukemia (ALL) is rare, it is the most common cancer that affects children. ALL is a cancer of the bone marrow and blood.

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Chordoma -

A very uncommon and insidious form of cancer, chordomas are tumors that can occur anywhere within the spine or the base of the skull. They are so rare that only about one in one million people per year can expect to be stricken by the disease.

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Merkel cell carcinoma -

Merkel cell carcinoma is a very rare and aggressive disease in which malignant cancer cells form in the skin. Typically, a lump develops on skin that receives prolonged exposure to the sun.

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Juxtaglomerular cell tumor -

Only around 100 cases of juxtaglomerular cell tumor (JCT) have been reported since 1967, when this condition was first identified. JCT is a kidney tumor of the juxtaglomerular cells, and often causes hypertension. Fortunately, JCT is often diagnosed as benign.

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NUT carcinoma -

An aggressive cancer that typically arises in the midline of the body—the lungs, for example—NUT carcinoma is devastatingly invasive and fatal. Less than 200 cases are diagnosed in the US each year.

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Thymic carcinoma -

Thymoma and thymic carcinoma are rare diseases in which malignant cancer cells form on the outside surface of the thymus, a specialized primary lymphoid organ of the immune system. Thymic carcinoma cells grow quickly an can rapidly spread to other parts of the body.

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Hepatoblastoma -

Hepatoblastoma is a rare, malignant tumor of the liver. It's a childhood cancer, typically affecting youngsters in the first three years of life.

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T-cell lymphoma -

Lymphoma is a type of blood cancer that develops when white blood cells called lymphocytes grow out of control. T-cell lymphomas are the uncommon and rare subtype of non-Hodgkin lymphomas. Prognosis is rarely encouraging.

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Synovial sarcoma -

Arising from different types of soft tissue, such as muscle or ligaments, usually in the arm, leg, or foot, synovial sarcoma accounts for 5% to 10% of soft-tissue tumors.

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Ewing sarcoma -

Ewing sarcoma is cancer that occurs primarily in the bone or soft tissue. It's most often found in the hip bones. Children and young adults are the most prone to Ewing sarcoma, which represents about 2% of childhood cancers.

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Adenoid cystic carcinoma -

Adenoid cystic carcinoma (ACC) is an uncommon type of cancer that usually develops in the salivary glands or other regions of the head and neck. Symptoms of ACC include a lump on the roof of the mouth, under the tongue, or on the bottom of the mouth.

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Esthesioneuroblastoma -

Esthesioneuroblastoma (ENB), also known as olfactory neuroblastoma, is a rare type of cancer that begins in the upper portion of the nasal cavity.

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Ganglioglioma -

Ganglioglioma is an extremely rare brain tumor commonly diagnosed in children and young adults. The disease accounts for approximately 1%–2% of all brain tumors.

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Leiomyosarcoma -

Leiomyosarcoma is a rare type of cancer that falls into the category of sarcomas, which generally arise from soft connective muscle tissue. Rare and aggressive, leiomyosarcoma is found most often in the abdomen or in the uterus.

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Heart cancer -

An extremely rare condition, heart cancer, or cardiac sarcoma, causes heart failure. So uncommon is this disease that no clinical trial results, meta-analyses, or treatment guidelines exist.

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Male breast cancer -

Commonly thought of as a disease that affects women, breast cancer does occur in men. It is a rare condition: about one out of every 100 breast cancers diagnosed in the United States is found in a man.

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Mast cell leukemia -

A hematological disease that may occur at any age, mast cell leukemia is a very rare and extremely aggressive subtype of acute myeloid leukemia.

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Parathyroid carcinoma -

This rare endocrine malignancy targets one of the four parathyroid glands that lie behind the thyroid. Parathyroid carcinoma is uncommon, but aggressive and life-threatening.

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Pheochromocytoma -

Pheochromocytoma is a rare tumor that forms in the center of one or both of the adrenal glands. Also known as an adrenal paraganglioma or a chromaffin cell tumor, most pheochromocytoma tumors are benign, with about 10% to 15% diagnosed as cancerous.

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Carcinoid tumor -

A type of slow-growing cancer that can arise in several places throughout your body, carcinoid tumors are cancerous and attack the neuroendocrine system—the body system that produces hormones.

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Angiosarcoma -

This rare and intrusive cancer starts in the endothelial cells that line the walls of blood vessels or lymphatic vessels. Angiosarcomas are most common in people over the age of 70, but only make up about 1% to 2% of all sarcomas.

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Periosteal osteosarcoma -

An uncommon type of bone cancer, periosteal osteosarcoma is so rare it makes up less than 6% of all osteosarcoma cases. A malignant bone tumor, the disease typically forms on the bones of the legs (tibia and femur).

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Hereditary diffuse gastric cancer -

Hereditary diffuse gastric cancer, or HDGC, is unusual in that it's an inherited condition associated with an increased risk of gastric (stomach) cancer. Its makeup means that parents can pass it on to their children. The cancer grows in different parts of the stomach, so it can be difficult to detect and treat. HDGC makes up only about 1% to 3% of all stomach cancer cases.

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Clear cell renal cell carcinoma -

So named for how the tumor looks under the microscope (the cells in it appear clear, like bubbles), clear cell renal cell carcinoma (ccRCC) is a type of kidney cancer that causes tumors to grow inside your kidneys. Relatively common in adults, ccRCC makes up just 2-6% of childhood and young adult kidney cancer cases.

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Cholangiocarcinoma -

Cholangiocarcinoma is a bile duct cancer that forms in the slender tubes (bile ducts) that carry the digestive fluid bile and connect the liver to the gall bladder and small intestine. On average, cholangiocarcinoma affects fewer than six in 100,000 people around the world.

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Esophageal cancer -

Esophageal cancer targets the hollow tube that connect your throat to your stomach and moves food and liquids from your mouth to the belly. The disease makes up about 1% of cancer cases in the United States.

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Kaposi sarcoma -

A rare type of disease caused by a virus, Kaposi sarcoma (also spelled as Kaposi's sarcoma) occurs in the cells lining lymph or blood vessels. It is one of the main types of cancer to affect people with HIV. The tumors of Kaposi sarcoma typically appear as painless, purplish spots on the legs, feet, or face.

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Appendiceal cancer -

Appendiceal cancer, also called appendix cancer, is extremely uncommon. It grows from cells that make up the lining of the appendix. Hard to detect, the cancer can spread to different parts of the abdomen directly from the affected organ.

Sources: (WHO) (World Economic Forum) (Cureus) (NORD) (Endocrinology, Diabetes & Metabolism Case Reports) (Brain Tumour Research) (National Cancer Institute) (CDC)

See also: Body parts that you can live without

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