Choriocarcinoma is a malignant proliferation of syncytial trophoblast cells that do not form placental villi. It is a relatively rare and highly malignant variant of gestational trophoblastic disease. Although choriocarcinoma is mostly observed after a molar pregnancy, it may be preceded by any gestational event. It has been shown that even a partial mole can transform into choricarcinoma. Incidence rates of choriocarcinoma differ widely throughout the world. In Europe and North America, choriocarcinoma is reported to affect one in every 30,000 to 40,000 pregnancies, and one in 40 molar pregnancies. In South East Asia, choriocarcinoma is reported to affect one in every 500-3000 pregnancies. Following livebirth, choriocarcinoma with metastatic disease are important sequele (31%)(Tidy et al 1995). In the same study the reported median interval between antecedent pregnancy and choriocarcinoma is five months. Multi agent chemotherapy is required in the majority of patients (82%) for the high risk group. The prognosis for choriocarcinoma after a normal gestation is poorer. The mortality rate is also significantly higher than non-molar abortion (21%). Effective treatment with oral Methotrexate in metastatic choriocarcinoma to the lung confirmed the highly sensitive nature of this tumour to chemotherapy agent.