A prospective randomized comparison of methotrexate, dactinomycin, and chlorambucil versus methotrexate, dactinomycin, cyclophosphamide, doxorubicin, melphalan, hydroxyurea, and vincristine in "poor prognosis" metastatic gestational trophoblastic disease: a Gynecologic Oncology Group study.
In 1981, the Gynecologic Oncology Group initiated a prospective randomized study in which patients with poor-prognosis gestational trophoblastic disease received either standard MAC chemotherapy (methotrexate, dactinomycin, and chlorambucil) or the modified CHAMOMA regimen (methotrexate, dactinomycin, cyclophosphamide, doxorubicin, melphalan, hydroxyurea, and vincristine). The protocol was closed in May 1986 because the modified CHAMOMA regimen was significantly more toxic and possibly less effective. There were 42 patients entered, with 22 receiving MAC and 20 receiving modified CHAMOMA. There have been six deaths due to disease in the modified CHAMOMA group and none in the MAC group. Five MAC failures and one modified CHAMOMA failure have been rescued by surgery and/or chemotherapy. All six of the patients who died on the modified CHAMOMA regimen had developed disease following a previous term pregnancy, but none had prior chemotherapy. All seven patients who were treated for gestational trophoblastic disease after term pregnancy in the MAC group were cured of disease. With the modified CHAMOMA regimen, 44% of patients had life-threatening hematologic toxicity, as compared with only 9% of the MAC patients. Thus, the standard MAC regimen appears to be at least equally effective and much less toxic than the modified CHAMOMA regimen, indicating a more favorable therapeutic index.
CHAMOCA is not recommended for GTN treatment as it is more toxic and not more effective than MAC. EMA/CO is currently the most widely used first-line combination chemotherapy for high-risk GTN, although this regimen has not been rigorously compared to other combinations such as MAC or FAV in RCTs. Other regimens may be associated with less acute toxicity than EMA/CO; however, proper evaluation of these combinations in high-quality RCTs that include long-term surveillance for secondary cancers is required. We acknowledge that, given the low incidence of GTN, RCTs in this field are difficult to conduct, hence multicentre collaboration is necessary.