hCG Monitoring during chemotherapy treatment
During chemo the serum and urine hCG is checked twice a week. Once the hCG becomes normal the markers are checked weekly until the treatment stops.
Dose delays and reductions for haematological toxicity
Guidelines for chemotherapy administration: We are keen to maintain the intensity of chemotherapy treatment. It is very rare for there to be appreciable myelosuppression with single agent Methotreaxtae.
In high risk disease with EMA-CO chemotherapy myelosuppression is fairly common and we frequently use G-CSF support (G-CSF 30mU for 3-4 days per week) to keep treatment on time.
As a general rule we use the following results obtained on the day of treatment to give the go ahead for chemotherapy:-
Neutrophils >1.0
Platelets > 75
Bleeding
PV or intraperitoneal bleeding can occur. Moderate bleeding usually responds to bed rest and chemotherapy treatment. Torrential bleeding may require treatment with a vaginal pack, emergency embolization and very rarely with hysterectomy. Overall less than 1.5% of GTD treated at Charing Cross patients have required one of these interventions over the past 25 years.
Choriocarcinoma Emergency Treatment of unwell patients
Patients who are acutely unwell from liver or CNS disease and particularly those with large lung metastases who are at risk of respiratory failure should be treated with emergency chemotherapy given as soon after admission as possible. Treatment should be given at night or weekends as these patients can deteriorate very rapidly.
We usually give emergency treatment with can be started with 1-2 days of EP. (Etoposide 100mg/m2 D 1+2, Cisplatin 20mg/m2 D1 + 2 the doses are as in BEP given for testicular cancer)
This treatment can be repeated weekly and then altered to EMA/CO or EP/EMA at a later point.
Hepatic Metastases
Due to their poorer overall response rate and higher risk of relapse, patients with hepatic metastases should be treated with using the EP/EMA protocol and continued for 8 weeks after the normalisation of the hCG level.
Cerebral Metastases
In GTT the outlook for patients with brain mets is surprisingly good with a survival rate of > 80%.
The CXH treatment for this is the high dose EMA(CNS)/CO, using an increased methotrexate dose (1gm/m2) combined with longer folinic acid rescue. In CNS disease the EMA(CNS)/CO chemotherapy is continued for 8 weeks after the hCG normalisation.
Intrathecal MTX is also given 12.5mg + 15mg FA on the EMA week until the serum hCG is normal at which point it is discontinued.
In the emergency situation with cerebral metastases, hi-dose dexamethasone is given followed by 2 day EP as above.
Surgery can be indicated for isolated superficial lesions or for cerebral haemorrhage.
CNS Prophylaxis
CXH policy is to give prophylaxis to low risk patients with lung mets and all of the high-risk patients.
Treatment is I-T MTX 12.5 mg (followed by oral FA 15mg at 24 hrs) on 3 occasions during the first 3 MTX courses, for the high risk patients it usually coincides with the CO treatment.
Respiratory Failure
In patients with large volume pulmonary lung mets oxygen support can be given but ventilation is contra-indicated, due to the risk of traumatic haemorrhage from the tumour vasculature.
Respiratory compromise can also result from tumour within the pulmonary vasculature, this can respond promptly to chemotherapy. Consideration can be given to anti-coagulation in these rare patients with tumour emboli.
Tumour Lysis Syndrome
This is rare in GTT and no special precautions need to be taken.