Choriocarcinoma

Choriocarcinomas are rare and aggressive tumours that develop from trophoblastic cellsthe basic structural and functional unit of all living things, which are specialised cells in the placenta. In most cases, choriocarcinomas are associated with pregnancy and develop in the placenta, however they can develop in other locations and not be associated with pregnancy in rare instances.

Germ cell tumours are a rare group of neoplasms that arise from primordial germ cellsa cell that develops into reproductive cells (eggs in females, sperm in males) – the cells responsible for developing into reproductive cells (gametes) such as ovum and sperm. These tumours typically originate in the gonads, which are the organs that produce gametes (ovaries in females and the testicles in males). These tumours are referred to as gonadal germ cell tumours. In some cases, germ cells can migrate to other parts of the body during early embryonic development, leading to tumoura tissue mass that forms from groups of unhealthy cells formation outside of the gonads later in life. These are known as extragonadal germ cell tumours, and are most commonly found in the brain, mediastinumthe space between the lungs that holds many important structures, including the heart, trachea and oesophagus, retroperitoneuma space located behind the abdomen that contains many important bodily structures, such as the kidneys, or sacrococcygeal region.

In some cases, choriocarcinomas can increase the levels of human chorionic gonadotropin (HCG), which is a hormonea chemical substance produced by glands in the endocrine system that regulates various functions in the body produced by the placenta (an organ that develops alongside a fetus during pregnancy) during early stages of pregnancy.

Choriocarcinomas are generally more common in females, with average age at diagnosisthe process of identifying a disease based on signs and symptoms, patient history and medical test results varying between subtypes. However, anyone can develop this disease.

Types of Choriocarcinoma

Choriocarcinomas can be classified by their location within the body, as well as whether or not they are associated with pregnancy.

Gestational and Non-Gestational Choriocarcinoma

Choriocarcinomas can be classified based on whether or not they are associated with pregnancy.

Gestational Choriocarcinoma

Gestational choriocarcinoma is a rare type of carcinomacancer arising from tissues that line organs that generally occurs after an untreated molar pregnancy. In rare instances, they can also develop from trophoblastic tissuea group of cells that work together to perform a function left after a miscarriage, abortion, or the delivery of a healthy baby.

Gestational choriocarcinoma is a type of gestational trophoblastic disease (GTD). For more information on GTDs, please refer to the Rare Cancers Australia Gestational Trophoblastic Disease page.

Non-Gestational Choriocarcinoma

Non-gestational choriocarcinoma is a very rare form of choriocarcinoma that is not associated with pregnancy. Unlike gestational choriocarcinoma, they can also develop in males and tend to be more aggressive.

Gonadal Choriocarcinoma

Gonadal embryonal carcinomas are more common, and develop in either the ovaries or testicles.

Ovarian Choriocarcinoma

Ovarian choriocarcinoma is a rare form of germ cell tumour that can develop as a part of a gestational or non-gestational choriocarcinoma. When not associated with pregnancy, ovarian choriocarcinomas are most commonly found in females before they reach puberty or after menopause. These tumours are often aggressive, but can have a good prognosisto predict how a disease/condition may progress and what the outcome might be when found early.

Testicular Choriocarcinoma

Testicular choriocarcinoma is a rare form of germ-cell tumour and often present as a part of a mixed germ-cell tumour (a cancera disease where abnormal cells split without control and spread to other nearby body tissue and/or organs containing cells from different germ-cell tumours). It is most commonly found in young adult males between the ages of 15-30. Testicular choriocarcinomas are often aggressive, and may not have as good of a prognosis as other types of choriocarcinoma.

Extragonadal Choriocarcinoma

Extragonadal choriocarcinomas are much less common than gonadal choriocarcinomas, and develop in areas other than the gonads.

Intracranial Choriocarcinoma

Intracranial choriocarcinomas are a rare type of germ-cell tumour that develops in the brain, most commonly in the pineal and suprasellar regions. It is most commonly found between the ages of 3-22, and has a male predominance. Intracranial choriocarcinomas are often aggressive, and may not have as good of a prognosis as other types of choriocarcinoma.

Mediastinal Choriocarcinoma

Mediastinal choriocarcinomas are a rare type of germ-cell tumour that develops in the mediastinum, and often present as a part of a mixed germ-cell tumour. Due to the rarity of this condition, the average age at diagnosis varies across reports and is not well-known. Mediastinal choriocarcinomas are more common in males, are often aggressive, and may not have as good of a prognosis as other types of choriocarcinoma.

Rare Extragonadal Choriocarcinomas

These types of choriocarcinomas are considered to be very rare:

• Retroperitoneal choriocarcinoma.
• Sacrococcygeal choriocarcinoma.

Treatment

If a choriocarcinoma is detected, it will be staged and graded based on size, metastasiswhen the cancer has spread to other parts of the body, also known as mets, and how the cancer cells look under the microscope. Stagingthe process of determining how big the cancer is, where it started and if it has spread to other areas and grading help your doctors determine the best treatment for you.

FIGO Staging System – Ovarian Choriocarcinomas

Ovarian cancers can be staged using the Federation of Gynaecologythe study of the female reproductive system and related diseases and Obstetrics (FIGO) system from stage I to IV:

• Stage I: cancer cells are confined to one or both ovaries only. This stage is also known as early-stage cancer.

• Stage II: cancer cells have grown deeper into nearby organs in the pelvis, such as the uterus, fallopian tubes, bladder and/or bowelportion of the digestive system that digests food (small bowel) and absorbs salts and water (large bowel); also called intestines. This is also known as localised cancer.

• Stage III: the cancer has become larger and has spread beyond the pelvis into the lining of the abdomen (peritoneumthe membrane that lines the abdominal cavity). Lymph nodes are also often affected. This is also known as advanced or metastatic cancer.

• Stage IV: the cancer has spread to more distant organs, such as the lungs or the liver. This is also known as advancedat a late stage, far along or metastatic cancer.

TMN Staging System

All other choriocarcinomas can be staged using the TNM staging system:

• T (tumour) indicates the size and depth of the tumour.

• N (nodea small lump or mass of tissue in your body) indicates whether the cancer has spread to nearby lymph nodessmall bean-shaped structures that filters harmful substances from lymph fluid.

• M (metastasis) indicates whether the cancer has spread to other parts of the body.

This system can also be used in combination with a numerical value, from stage 0-IV:

• Stage 0: this stage describes cancer cells in the place of origin (or ‘in situ’) that have not spread to nearby tissue.

• Stage I: cancer cells have begun to spread to nearby tissue. It is not deeply embedded into nearby tissue and had not spread to lymph nodes. This stage is also known as early-stage cancer.

• Stage II: cancer cells have grown deeper into nearby tissue. Lymph nodes may or may not be affected. This is also known as localisedaffecting only one area of body cancer.

• Stage III: the cancer has become larger and has grown deeper into nearby tissue. Lymph nodes are generally affected at this stage. This is also known as localised cancer.

• Stage IV: the cancer has spread to other tissues and organs in the body. This is also known as advanced or metastatic cancer.

Cancers can also be graded based on the rate of growth and how likely they are to spread:

• Gradea description of how abnormal cancer cells and tissue look under a microscope when compared to healthy cells I: cancer cells present as slightly abnormal and are usually slow growing. This is also known as a low-grade tumour.

• Grade II: cancer cells present as abnormal and grow faster than grade-I tumours. This is also known as an intermediate-grade tumour.

• Grade III: cancer cells present as very abnormal and grow quickly. This is also known as a high-grade tumour.

Once your tumour has been staged and graded, your doctor may recommend genetic testinga procedure that analyses DNA to identify changes in genes, chromosomes and proteins, which can be used to analyse tumour DNA to help determine which treatment has the greatest chance of success, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.

Treatment Options

Treatment is dependent on several factors, including location, age, stage of disease and overall health.

Treatment options for embryonal carcinomas may include:

• Surgerytreatment involving removal of cancerous tissue and/or tumours and a margin of healthy tissue around it to reduce recurrence to remove as much of the tumour as possible – will vary based on tumour location.

• Chemotherapya cancer treatment that uses drugs to kill or slow the growth of cancer cells, while minimising damage to healthy cells.

• Clinical trialsresearch studies performed to test new treatments, tests or procedures and evaluate their effectiveness on various diseases.
• Palliative carea variety of practices and exercises used to provide pain relief and improve quality of life without curing the disease.

Gonadal Choriocarcinoma Treatment and Fertility

Treatment for ovarian and testicular choriocarcinomas may make it difficult to conceive a child. If fertility is important to you, discuss your options with your doctor and a fertility specialist prior to the commencement of treatment.

Risk factors

Because of how rare non-gestational choriocarcinomas are, there has been limited research done into the riskthe possibility that something bad will happen factors of this disease. However, a link has been found between the development of mediastinal germ-cell tumours and males with the genetic disorder Klinefelter syndrome.

Risk factors for gestational choriocarcinomas can be found on the Rare Cancers Australia Gestational Trophoblastic Disease page.

Symptoms

The symptoms of choriocarcinoma will vary based on location.

Symptoms of Ovarian Choriocarcinoma

Symptoms of ovarian choriocarcinoma may include:

• Lower abdominal pain.

• Abdominal swelling.

• Unusual vaginal bleeding not associated with menstruation.

• Precocious (early) puberty.

• Changes in menstrual periods, such as irregular periods, unusual vaginal bleeding, or vaginal bleeding post menopause.

• Mild hirsutism (growth of excessive male-pattern hair in women).

• Infertility.

Symptoms of Testicular Choriocarcinoma

Symptoms of testicular choriocarcinoma may include:

• A painless massa growth of cells that come together to make a lump, may or may not be cancer in the testicle(s).

• Changes in testicular size and/or shape.

• A feeling of heaviness and/or unevenness in the scrotum.

• Pain or discomfort in the testicle(s) and/or scrotum (less common).

• Aches in the lower abdomenstomach, stomach area, belly, back and/or scrotum.

• Enlargement of breast tissue.

• Hyperthyroidism.

• Haemoptysiscoughing up blood.

• Seizures.

• Confusion.

Symptoms of Intracranial Choriocarcinoma

Symptoms of intracranial choriocarcinoma vary based on location.

Pinel Gland Region

• Hydrocephalusa build up of cerebrospinal fluid (CSF) in the brain, causing pressure and potentially damaging brain tissue, which carries its own set of symptoms:

• Headaches.

• Nauseato feel sick or likely to vomit and/or vomiting.

• Difficulties with eye movement.

• Difficulties with balance.

• Difficulties with walking.

• Fatiguea state of extreme tiredness or exhaustion, can be physical or mental.

• Memory problems.

• Seizures.

• Behavioural and/or cognitive changes.
• Vision changes, such as double vision and difficulty looking up.

Suprasellar region

• Irregular sleep.

• Early puberty in children.

• Delayed puberty in children.

• Stunted growth in children.

• Changes in eyesight, such as loss of peripheral vision or loss of vision.

• Diabetes insipidus (disorder causing fluid imbalance in the body), which carries its own set of symptoms:

• Polyuriafrequent urination.

• Intense thirst.

• Isolated growth hormone deficiency, which carries its own set of symptoms:

• Poor growth.

• Impaired hair and/or nail growth.

• Delayed development of teeth.

• Delayed puberty.

• Hypoglycaemialow blood sugar in infants and toddlers.

• Decreased energy levels.
• Increased fat around the face and/or abdomen.

Symptoms of Mediastinal Choriocarcinoma

Symptoms of mediastinal choriocarcinoma may include:

• Dyspneadifficulty breathing, shortness of breath.

• Chest pain.

• Persistent cough.

• Haemoptysis.

• Superior vena cava syndrome, which has its own set of symptoms:

• Coughing.

• Dyspnea.

• Swelling of the face, neck, and/or upper arms.

• Syncopefainting or passing out.

• Headache.

• Cardiac tamponade (compression of the heart caused by fluid build-up), which carries its own set of symptoms:

• Hypotensionlow blood pressure.

• Dyspnea.
• Light-headedness.

Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.

Diagnosis

If your doctor suspects you have a choriocarcinoma, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment:

• Physical examinationan examination of your current symptoms, affected area(s) and overall medical history.

• Blood teststesting done to measure the levels of certain substances in the blood.

• Imagingtests that create detailed images of areas inside the body tests, potentially including:

• • Ultrasounda type of medical imaging that uses soundwaves to create detailed images of the body  .

• • MRI (magnetic resonance imaging)a type of medical imaging that uses radiowaves, a strong magnet and computer technology to create detailed images of the body.

• • CT (computed tomography) scana type of medical imaging that uses x-rays and computer technology to create detailed images of the body.

• • PET (positron emission tomography) scana type of medical imaging that uses radioactive tracers to create detailed images of the body.

• • Chest X-raya type of medical imaging that uses x-ray beams to create detailed images of the body   (mediastinal embryonal carcinomas).

• Exploratory surgerya surgical procedure used for conditions that cannot be confirmed by scans and tests alone.
• Biopsyremoval of a section of tissue to analyse for cancer cells (where possible).

Exploratory Surgery

After conducting the previously mentioned diagnostic tests, your doctor may strongly suspect that you have testicular or ovarian cancer. In most cases, a diagnosis can be confirmed after a biopsy, where a section of tissue is removed and analysed for cancer cells. However, doctors avoid conducting a biopsy in patients who have suspected testicular and ovarian cancer as there is a small risk that making an incision in the scrotum or ovary could cause cancer cells to spread.  As such, the only way to confirm the diagnosis safely is to remove the affected gonad.

Once the gonad has been removed, it will be sent to a laboratory and analysed for cancer cells.

References

• NCBI – Mediastinal Choriocarcinoma
• Pathology Outlines – Ovarian Choriocarcinoma
• Pathology Outlines – Testicular Choriocarcinoma
• Radiopaedia – Choriocarcinoma overview
• Radiopaedia – Mediastinal Choriocarcinoma