Rhabdoid tumoura tissue mass that forms from groups of unhealthy cells predisposition syndrome (RTPS) is a rare genetic condition that increases the riskthe possibility that something bad will happen of developing certain types of cancers, most commonly rhabdoid tumours. It is caused by genetic mutations in SMARCB1 and SMARCA4 tumour suppressor genes.
Familial cancera disease where abnormal cells split without control and spread to other nearby body tissue and/or organs syndromes, also known as hereditary cancer syndromes, are rare conditions that cause an increased risk of cancer as the result of inherited genetic mutations in certain cancer-related genes. They can affect both adults and children, however they generally develop in people at a younger age than normal. While familial cancer syndromes are not classified as cancer, they are equally as severe and can be life-threatening as they are associated with the development of various tumours throughout the body. Having a familial cancer syndrome does not guarantee the development of cancer, however the risk of developing cancer is higher than those who do not have a familial cancer syndrome.
RTPS is generally diagnosed equally among the sexes, and are generally diagnosed before three years of age. However, anyone can develop this disease.
Types of Rhabdoid Tumour Predisposition Syndromes
There are two primary types of RTPS, which are classified based on the genetic mutation that causes the disease.
Rhabdoid Tumour Predisposition Syndrome Type 1 (RTPS1)
Rhabdoid tumour predisposition syndrome type 1 (RTPS1) is the most common subtype, and is caused by a mutation in the SMARCB1 gene. The most common tumour associated with this subtype is atypical teratoid/rhabdoid tumours (ATRTs) of the central nervous system, and has been associated with the development of peripheral nerve sheath tumours (most commonly schwannomas) and other tumours.
Rhabdoid Tumour Predisposition Syndrome Type 2 (RTPS2)
Rhabdoid tumour predisposition syndrome type 2 (RTPS2) is a less common subtype, and is caused by a mutation in the SMARCA4 gene. The most common tumour associated with this subtype is small cell carcinoma of the ovary – hypercalcemic type (SCCOHT), however it has also been associated with the development of ATRTs and other tumours.
RTPS Related Tumours
RTPS is most commonly associated with the development of atypical teratoid rhabdoid tumours (ATRTs), however it has also been linked to other types of tumours. Some examples include:
- Rhabdoid tumours, most commonly ATRTs.
- Small cell ovarian cancer, most commonly the hypercalcaemic subtype.
- Cribriform neuroepithelial tumours (CRINETs).
Treatment
When cancers are detected, they are 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 cellsthe basic structural and functional unit of all living things 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 helps your doctors determine the best treatment for you. However, each patient with RTPS will present with a unique disease behaviour, with varying tumour locations and symptoms. As such, there is no one treatment method that will work for everyone, and there is no standard staging system for this disease. Instead of staging and grading, your doctor will recommend a treatment plan based on the following factors:
- Type of tumours present.
- Whether the tumours are malignantcancerous, may grow and spread to other areas of the body (cancerous) or benignnot cancerous, can grow but will not spread to other body parts (non-cancerous).
- Tumour location.
- Whether or not malignant tumours have metastasised.
- Your age.
- General health.
- Your treatment preferences.
Your doctor may also 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 for tumours associated with RTPS 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(s) as possible – these will vary based on tumour type and location.
- Chemotherapya cancer treatment that uses drugs to kill or slow the growth of cancer cells, while minimising damage to healthy cells.
- Radiation therapya treatment that uses controlled doses of radiation to damage or kill cancer cells.
- Immunotherapya treatment that uses a person's immune system to fight cancer.
- Targeted therapymedication that targets specific molecular features of cancer cells.
- Watch and waitthe close monitoring of a cancer without giving treatment until symptoms appear or worsen.
- 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.
Cancer Screening
Once a diagnosisthe process of identifying a disease based on signs and symptoms, patient history and medical test results of RTPS has been confirmed, implementing a targeted screeningtesting for cancer or conditions that can lead to cancer before symptoms appear, also known as cancer screening plan becomes essential due to the increased risk of developing certain cancers. The content of this plan will vary from person to person based on the genetic mutation involved, your family’s history of cancer and the types of cancers that may be present. It will also outline the routine tests you should have and how regularly you should have them. Recommendations for RTPS may vary by age.
Birth to Eighteen Months Old
From birth to 18 months old, intensive surveillance may be recommended. The following may be required every 1-3 months:
- Neurological examinationan assessment of sensory and motor functions, such as vision, balance and coordination.
- Ultrasounda type of medical imaging that uses soundwaves to create detailed images of the body of the abdomenstomach, stomach area, belly, head and/or neck.
- MRI of the brain and spine. Rarely, whole-body MRI might be required.
Nineteen Months Old to Five Years Old
The following may be recommended every three months:
- Neurological examination.
- Ultrasound of the abdomen, head and/or neck.
- MRI of the brain and spine.
After Five Years Old
As the risk of RTPS dramatically decreases after this time, surveillance may be required less frequently and may include:
- Physical and neurological examinations every six months.
- Annual MRI of the whole body.
- Abdominal and pelvic ultrasounda type of medical imaging that uses sound waves to create detailed images of the organs and structures within the pelvis, including the uterus, ovaries, and surrounding tissues every six months in individuals with small cell ovarian cancer.
Screening options for RTPS may evolve as new technologies are developed and our understanding of the condition grows. It is essential to discuss your individual circumstances with your healthcare team to determine the most appropriate screening plan for you.
Risk factors
RTPS is caused by a genetic mutation in either the SMARCB1 or SMARCA4 tumour suppressor genes, which act to inhibit cell growth to prevent overproduction of cells and the development of tumours. It is an autosomal dominant disease, which means that you have a 50% chance of developing the condition if one of your parents carries the mutation.
Symptoms
The symptoms of RTPS often vary by the type(s) of tumours present. General symptoms of RTPS may include:
- Abdominal massa growth of cells that come together to make a lump, may or may not be cancer.
- Hypertensionhigh blood pressure.
- Haematuriathe presence of blood in urine.
- Hypercalcaemiaexcess levels of calcium in the blood.
- Difficulty urinating.
- Difficulties with balancing and coordination and/or walking.
- Slowed speech.
- Headaches.
- General weakness and fatiguea state of extreme tiredness or exhaustion, can be physical or mental.
- Seizures.
- Diplopiaseeing two images of a single object, also known as double vision and/or other eye problems.
- Nauseato feel sick or likely to vomit and/or vomiting.
- Irritability.
- Slowed growth.
- Changes in eating habits.
- Delayed developmental milestones, such as sitting up, walking and talking.
- Abdominal bloating/swelling.
- Abdominal/pelvic/lower back pain and/or pressure.
- Unexplained weight loss/loss of appetite.
- Fatigue.
Symptoms related to specific tumours can be found on our knowledgebase.
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 tumours associated with RTPS, they may order some of the following tests to confirm the diagnosis and refer you to a specialist for treatment. The tests required for diagnosis will often vary based on the symptoms present, and where the tumour(s) are suspected to be located.
- Physical examinationan examination of your current symptoms, affected area(s) and overall medical history.
- Genetic testing.
- Neurological examination.
- Blood teststesting done to measure the levels of certain substances in the blood.
- Urine teststesting done to measure the levels of certain substances in the urine.
- Imagingtests that create detailed images of areas inside the body tests, potentially including:
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- 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.
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- CT (computed tomography) scana type of medical imaging that uses x-rays and computer technology to create detailed images of the body.
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- PET (positron emission tomography) scana type of medical imaging that uses radioactive tracers to create detailed images of the body.
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- Ultrasound.
- Exploratory surgerya surgical procedure used for conditions that cannot be confirmed by scans and tests alone, such as an endoscopya procedure that involves inserting a long, flexible tube with a light and small camera (endoscope) into the body to view internal organs.
- Biopsyremoval of a section of tissue to analyse for cancer cells.