Todays infoblog has been provided by Kam Singh, Lead Clinical Nurse Specialist in Gestational Trophoblastic Disease/Ovarian Germ Cell Malignancy at Weston Park Hospital in Sheffield.
Later today we will share the story of Lisa who was diagnosed with a twin molar pregnancy
Please share with you family, friends and colleagues to help raise awareness of this very rare condition
Gestational Trophoblastic Disease is a rare condition that can develop during pregnancy. The placenta is the organ that is normally formed as part of a healthy pregnancy and it produces hormones that help the baby grow and develop. It is made up of millions of cells called trophoblasts.
In trophoblastic disease there is an abnormal overgrowth of all or part if the placenta. The trophoblastic cells do not grow as they should, and form a mass of abnormal cells in the uterus. The growth can be either benign or malignant. A malignant GTD is commonly called gestational trophoblastic neoplasia (GTN).
How does this happen?
We do not know why this occurs but we do know there is a problem right at the beginning during fertilisation. The diagram below shows how an egg normally develops, is fertilised and then implants in the wall of the uterus. In a molar pregnancy at the time of fertilisation there is a problem with either the maternal chromosomes being lost as in a complete mole or there being two sets of chromosomes from the father and one from the mother as in a partial molar pregnancy.
There are three main types of GTN – molar pregnancy, choriocarinoma and placental site trophoblastic tumour. All gestational trophoblastic growths release the pregnancy hormone human chorionic gonadotrophin (hCG)
In the majority of cases a molar pregnancy is benign and can be successfully treated by surgery. In these cases the hormone levels of hCG return to normal. However, for a small number of patients, part of the mole remains and can grow and spread to other parts of the body, causing a rise in the hCG. If the molar tissue remains and hCG levels are rising, it can also be called an invasive mole or persistent trophoblastic disease.
There are 3 screening centres in the UK for monitoring patients with gestational trophoblastic disease (Dundee for Scotland, Sheffield for North of England and North Wales and London for the rest of the UK, Wales and Ireland). There are only 2 specialist treatment centres in the UK (Sheffield, Weston Park Hosptial for North of England and North Wales and London, Charing Cross Hospital for the rest of the UK, Scotland, Wales and Ireland). In Sheffield we register approxiately 600 patients a year for GTD and around 5-6% will have persisitent disease and require chemotherapy treatment.
These patients are asked to attend one of the treatment centres for staging investigatons. Patients will have scans and bloods and then are scored using a scoring system to determine which treatment they will start. A score of 0-6 is categorised as low risk which involves intramuscular chemotherapy injections every other day for 4 injections, a rest week then the cycle is repeated every 2 weeks. A score of 7 or above is categorised as high risk and involves intravenous weekly chemotherapy. As long as there are no complications patients who score low risk will stay in hospital for at least 3 days on their first cycle. High risk patients maybe in for at least a week or more on their first cycle. We try and organise some chemotherapy injections in local hospitals the first cycle is always in Sheffield and patients will attend every two weeks.
The hCG level is the indicator of how many cycles of chemotherapy patients will have. We like to see the hCG level half after each cycle sometimes the level slows down or begins to rise. This indicators resistance to the chemotherapy and patients will require a change of treatment. For patients who score low risk treatment usually lasts between 4 – 6 months. For those who score high risk it can be between 6-12 months.
Women receiving treatment for GTN face a unique set of challenges associated with the loss of a pregnancy and a cancer diagnosis. It can be a very difficult journey having a specialised centre for GTD plays a fundamental role in ensuring these patients are well supported throughout their journey.