BACKGROUND
The purpose of the study was to determine the activity and toxicity of pulse dactinomycin as salvage treatment of patients with low‐risk gestational trophoblastic neoplasia (GTN) who failed methotrexate therapy.
METHODS
Eligible patients had persistent/recurrent low‐risk GTN defined by changes in serum human chorionic gonadotropin (hCG) levels (<10% fall over 3 consecutive weekly titers, >20% rise over the previous value, or a rise after attaining institutional normal [>5 mu/mL]); World Health Organization (WHO) score 2–6; Gynecologic Oncology Group (GOG) performance status 0–1; and previous treatment restricted to methotrexate. Dactinomycin administration was 1.25 mg/m2 intravenous (i.v.) every 2 weeks until documented complete response (CR) or treatment failure. CR was defined as an institutional normal serum hCG level sustained for ≥4 consecutive weeks; treatment failure was a <10% fall (3 assays over 4 weeks) or >20% rise (over previous value) in hCG serum level. Levels were monitored biweekly × 8 weeks beyond the first normal value, then monthly × 10.
RESULTS
Five of 44 enrolled patients were ineligible due to choriocarcinoma and normal pretreatment serum hCG level (2 each), no history of methotrexate (1), and 1 patient with documented phantom hCG syndrome was unevaluable. In all, 28 of 38 (74%) evaluable patients attained CR. The median number of cycles was 4 (range, 2–10). Severe toxicity was minimal, causing no patient to discontinue therapy. All treatment failures achieved a CR after receiving subsequent chemotherapy; 3 patients also underwent hysterectomy.
CONCLUSION
Pulse dactinomycin is an active regimen for patients withlow‐risk GTN who fail previous methotrexate therapy. Cancer 2006. © 2006 American Cancer Society.