A retrospective study to evaluate single agent methotrexate treatment in low risk gestational choriocarcinoma in the United Kingdom

Abstract Objective To determine whether single agent chemotherapy with intramuscular methotrexate 50 mg administered on days 1, 3, 5, and 7 and oral folinic acid 15 mg administered on days 2, 4, 6, and 8 in 2 weekly cycles (IM MTX/FA) is an effective treatment regimen for patients with low risk gestational choriocarcinoma. Method Electronic databases were searched to identify patients with gestational choriocarcinoma at the Sheffield and Charing Cross supra-regional trophoblastic disease centres from January 2000 to December 2011. Clinical notes of low risk patients with FIGO score 0–6 were retrospectively reviewed to assess treatment outcomes and subsequent relapse. Results 65 patients were identified with low risk choriocarcinoma. Serum hCG levels normalised in 24 patients without the requirement of chemotherapy (19 with histological confirmation, 4 highly suspicious histology and 1 clinical diagnosis). Of 23 patients with histologically confirmed choriocarcinoma, 8 (35%) had a sustained complete response to IM MTX/FA and did not relapse. Both patients with FIGO score 6, and 1 patient with FIGO stage III metastatic disease developed resistance to IM MTX/FA and required further treatment. Despite the development of drug resistance or relapse all patients were successfully salvaged by subsequent treatments. Conclusions Not all patients with low risk choriocarcinoma that have had primary intervention prior to staging, such as surgical resection or uterine evacuation will require chemotherapy, providing hCG levels continue to decline to normal. Low risk (FIGO 0–5) patients should initially receive IM MTX/FA due to its low toxicity, outpatient administration and reasonable efficacy. Patients with FIGO score 6 or FIGO stage III disease should make an informed choice between IM MTX/FA and combination chemotherapy.