Risk of a repeat GTD
The risk of a repeat GTD is approximately 1 in 100, compared with approximately 1 in 1000 risk in the general population. Especially women whose hCG levels remain significantly elevated are at risk of developing a repeat GTD. Persistent trophoblastic disease
The term «persistent trophoblastic disease» (PTD) is used when after treatment of a molar pregnancy, some molar tissue is left behind and again starts growing into a tumour. Although PTD can spread within the body like a malignant cancer, the overall cure rate is nearly 100%.In the vast majority of patients, treatment of PTD consist of chemotherapy. Only about 10% of patients with PTD can be treated successfully with a second curettage. GTD coexisting with a normal fetus, also called "twin pregnancy"
In some very rare cases, a GTD can coexist with a normal fetus. This is called a "twin pregnancy". These cases should be managed only by experienced clinics, after extensive consultation with the patient. Because successful term delivery might be possible, the pregnancy should be allowed to proceed if the mother wishes, following appropriate counselling. The probability of achieving a healthy baby is approximately 40%, but there is a risk of complications, e.g. pulmonary embolism and pre-eclampsia. Compared with women who simply had a GTD in the past, there is no increased risk of developing persistent GTD after such a twin pregnancy.In few cases, a GTD had coexisted with a normal pregnancy, but this was discovered only incidentally after a normal birth. Epidemiology
Overall, GTD is a rare disease.
Eighteen months after the CRADA, BMS  filed a new drug application (NDA), which was given FDA approval at the very end of 1992. Although there was no patent on the compound, the provisions of the Waxman-Hatch Act gave Bristol-Myers Squibb five years exclusive marketing rights. In 1990, BMS applied to trademark the name taxol as Taxol(R). This was controversially approved in 1992. At the same time, paclitaxel replaced taxol as the generic (INN) name of the compound. Critics, including the journal Nature, argued the name taxol had been used for more than two decades and in more than 600 scientific articles and suggested the trademark should not have been awarded and the BMS should renounce its rights to it. BMS argued changing the name would cause confusion among oncologists and possibly endanger the health of patients. BMS has continued to defend its rights to the name in the courts. BMS has also been criticized for misrepresentation by Goodman and Walsh, who quote from a company report saying "It was not until 1971 that ... testing ... enabled the isolation of paclitaxel, initially described as compound 17". This quote is, strictly speaking, accurate: the objection seems to be that this misleadingly neglects to explain that it was the scientist doing the isolation who named the compound taxol and it was not referred to in any other way for more than twenty years. Annual sales peaked in 2000, reaching US$1.6 billion; paclitaxel is now available in generic form.